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Sample records for lat electron flux

  1. Searching for Dark Matter Signatures in the GLAST LAT Electron Flux

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander; Profumo, Stefano

    2008-01-01

    We explored several viable scenarios of how LAT might observe DM, when the spectral feature is predicted to be observed in the HE electron flux It has been demonstrated elsewhere that LAT will be capable to detect HE electrons flux in energy range from 20 GeV to - 1 TeV with 520% energy resolution and good statistics If there is a DM-caused feature in the HE electron flux (in the range 20 GeV - 1 TeV), LAT will be the best current instrument to observe it!

  2. LAT Perspectives in Detection of High Energy Cosmic Ray Electrons

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander; Ormes, J. F.; Funk, Stefan

    2007-01-01

    The GLAST Large Area Telescope (LAT) science objectives and capabilities in the detection of high energy electrons in the energy range from 20 GeV to approx. 1 TeV are presented. LAT simulations are used to establish the event selections. It is found that maintaining the efficiency of electron detection at the level of 30% the residual hadron contamination does not exceed 2-3% of the electron flux. LAT should collect approx. ten million of electrons with the energy above 20 GeV for each year of observation. Precise spectral reconstruction with high statistics presents us with a unique opportunity to investigate several important problems such as studying galactic models of IC radiation, revealing the signatures of nearby sources such as high energy cutoff in the electron spectrum, testing the propagation model, and searching for KKDM particles decay through their contribution to the electron spectrum.

  3. Fermi LAT Observations of Cosmic-Ray Electrons

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2011-01-01

    Designed as a gamma-ray instrument, the LAT is a capable detector of high energy cosmic ray electrons. The LAT is composed of a 4x4 array of identical towers. Each tower has a Tracker and a Calorimeter module. Entire LAT is covered by segmented Anti-Coincidence Detector (ACD). The electron data analysis is based on that developed for photons. The main challenge is to identify and separate electrons from all other charged species, mainly CR protons (for gamma-ray analysis this is provided by the Anti-Coincidence Detector)

  4. Electron heat flux instability

    NASA Astrophysics Data System (ADS)

    Saeed, Sundas; Sarfraz, M.; Yoon, P. H.; Lazar, M.; Qureshi, M. N. S.

    2017-02-01

    The heat flux instability is an electromagnetic mode excited by a relative drift between the protons and two-component core-halo electrons. The most prominent application may be in association with the solar wind where drifting electron velocity distributions are observed. The heat flux instability is somewhat analogous to the electrostatic Buneman or ion-acoustic instability driven by the net drift between the protons and bulk electrons, except that the heat flux instability operates in magnetized plasmas and possesses transverse electromagnetic polarization. The heat flux instability is also distinct from the electrostatic counterpart in that it requires two electron species with relative drifts with each other. In the literature, the heat flux instability is often called the 'whistler' heat flux instability, but it is actually polarized in the opposite sense to the whistler wave. This paper elucidates all of these fundamental plasma physical properties associated with the heat flux instability starting from a simple model, and gradually building up more complexity towards a solar wind-like distribution functions. It is found that the essential properties of the instability are already present in the cold counter-streaming electron model, and that the instability is absent if the protons are ignored. These instability characteristics are highly reminiscent of the electron firehose instability driven by excessive parallel temperature anisotropy, propagating in parallel direction with respect to the ambient magnetic field, except that the free energy source for the heat flux instability resides in the effective parallel pressure provided by the counter-streaming electrons.

  5. Fermi LAT detection of increasing gamma-ray flux from B2 1520+31

    NASA Astrophysics Data System (ADS)

    Sanchez, David

    2010-11-01

    The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has detected enhancement of the gamma-ray flux of a source positionally consistent with the Flat Spectrum Radio Quasar B2 1520+31 (RA: 15 22 09.99 , Dec: +31 44 14.4 , J2000, A. J. Beasley et al. 2002, ApJS, 41, 13 ) with a redshift of z=1.487 (D. Sowards-Emmerd et al. 2005, ApJ, 626, 95). Preliminary analysis indicates that the source flux was (1.8±0.3)x10-6 photons cm-2 s-1 (E>100 MeV, where errors are statistical only) on November 18.

  6. Measuring 10-1000 GeV Cosmic Ray Electrons with GLAST/LAT

    SciTech Connect

    Moiseev, Alexander A.; Ormes, Jonathan F.; Moskalenko, Igor V.

    2007-07-16

    We present here the capabilities of the GLAST Large Area Telescope to detect cosmic ray high-energy (HE) electrons in the energy range from 10 GeV to 1 TeV. We also discuss the science topics that can be investigated with HE electron data and quantify the results with LAT instrument simulations. The science topics include CR propagation, calibration of the IC gamma-ray model, testing hypotheses regarding the origin of HE energy cosmic-ray electrons, searching for any signature of Kaluza Klein Dark Matter annihilation, and measuring the HE electron anisotropy. We expect to detect {approx} 10{sup 7} electrons above 20 GeV per year of LAT operation.

  7. Analysis of the cumulative neutrino flux from Fermi LAT blazar populations using 3 years of IceCube data

    NASA Astrophysics Data System (ADS)

    Glüsenkamp, Thorsten

    2016-07-01

    The recent discovery of a diffuse neutrino flux up to PeV energies raises the question of which populations of astrophysical sources contribute to this diffuse signal. One extragalactic candidate source population to produce high-energy neutrinos are Blazars. We present results from a likelihood analysis searching for cumulative neutrino emission from Blazar populations selected with the 2nd Fermi LAT AGN catalogue (2LAC) using an IceCube data set that has been optimized for the detection of individual sources. In contrast to previous searches with IceCube, the investigated populations contain up to hundreds of sources, the biggest one being the entire Blazar sample measured by the Fermi-LAT. No significant neutrino signal was found from any of these populations. Some implications of this non-observation for the origin of the observed PeV diffuse signal will be discussed.

  8. New Results on High Energy Cosmic Ray Electrons Observed with Fermi LAT and Their Implications on the Models of Pulsars

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2010-01-01

    This viewgraph presentation describes, in detail, the Fermi Large Area Telescope (LAT) and GLAST Burst Monitor (GBM). Observations made from the June 11, 2008 launch and a discussion of observations made of high energy cosmic ray electrons is also presented.

  9. Anisotropies in the flux of cosmic ray electrons and positrons

    NASA Astrophysics Data System (ADS)

    Manconi, S.; Di Mauro, M.; Donato, F.

    2017-05-01

    High energy cosmic ray electrons and positrons probe the local properties of our galaxy. In fact, regardless of the production mechanism, electromagnetic energy losses limit the typical propagation scale of GeV-TeV electrons and positrons to a few kpc. In the diffusion model, the presence of nearby and dominant sources may produce an observable dipole anisotropy in the cosmic ray fluxes. We present a detailed study on the role of anisotropies from nearby sources in the interpretation of present cosmic ray electron and positrons fluxes. Predictions for the dipole anisotropy from known astrophysical sources as Supernova Remnants (SNRs) and pulsars taken from the Green and the Australia Telescope National Facility (ATNF) catalogs are shown. The results are obtained from models compatible with the most recent AMS-02 data on electrons and positrons fluxes. In particular, anisotropies for single sources as well as for a distribution of catalog sources are discussed. We compare our results with current anisotropy upper limits from the Fermi-LAT and PAMELA experiments, showing that the search of anisotropy in the electron and positron fluxes represents a complementary tool to inspect the properties of close SNRs, as for example the Vela SNR.

  10. Constraints on dark matter models from a Fermi LAT search for high-energy cosmic-ray electrons from the Sun

    DOE PAGES

    Ajello, M.; Atwood, W. B.; Baldini, L.; ...

    2011-08-15

    During its first year of data taking, the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope has collected a large sample of high-energy cosmic-ray electrons and positrons (CREs). We present the results of a directional analysis of the CRE events, in which we searched for a flux excess correlated with the direction of the Sun. Two different and complementary analysis approaches were implemented, and neither yielded evidence of a significant CRE flux excess from the Sun. Here, we derive upper limits on the CRE flux from the Sun’s direction, and use these bounds to constrain two classes ofmore » dark matter models which predict a solar CRE flux: (1) models in which dark matter annihilates to CREs via a light intermediate state, and (2) inelastic dark matter models in which dark matter annihilates to CREs.« less

  11. Constraints on dark matter models from a Fermi LAT search for high-energy cosmic-ray electrons from the Sun

    SciTech Connect

    Ajello, M.; Atwood, W. B.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bottacini, E.; Bouvier, A.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cecchi, C.; Charles, E.; Chekhtman, A.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Cutini, S.; de Angelis, A.; de Palma, F.; Dermer, C. D.; Digel, S. W.; do Couto e Silva, E.; Drell, P. S.; Favuzzi, C.; Fegan, S. J.; Focke, W. B.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Gehrels, N.; Germani, S.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Guiriec, S.; Gustafsson, M.; Hadasch, D.; Iafrate, G.; Jóhannesson, G.; Johnson, A. S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kuss, M.; Latronico, L.; Lionetto, A. M.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mizuno, T.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Naumann-Godo, M.; Norris, J. P.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; Ormes, J. F.; Ozaki, M.; Paneque, D.; Panetta, J. H.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Ritz, S.; Schalk, T. L.; Sgrò, C.; Siegal-Gaskins, J.; Siskind, E. J.; Smith, P. D.; Spandre, G.; Spinelli, P.; Suson, D. J.; Takahashi, H.; Tanaka, T.; Thayer, J. G.; Thayer, J. B.; Tibaldo, L.; Tosti, G.; Troja, E.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vilchez, N.; Waite, A. P.; Wang, P.; Winer, B. L.; Wood, K. S.; Yang, Z.; Zimmer, S.

    2011-08-15

    During its first year of data taking, the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope has collected a large sample of high-energy cosmic-ray electrons and positrons (CREs). We present the results of a directional analysis of the CRE events, in which we searched for a flux excess correlated with the direction of the Sun. Two different and complementary analysis approaches were implemented, and neither yielded evidence of a significant CRE flux excess from the Sun. Here, we derive upper limits on the CRE flux from the Sun’s direction, and use these bounds to constrain two classes of dark matter models which predict a solar CRE flux: (1) models in which dark matter annihilates to CREs via a light intermediate state, and (2) inelastic dark matter models in which dark matter annihilates to CREs.

  12. Electron Flux of Radiation Belts Animation

    NASA Image and Video Library

    This animation shows meridional (from north-south) plane projections of the REPT-A and REPT-B electron flux values. The animation first shows the expected two-belt Van Allen zone structure; from Se...

  13. Atmospheric electron flux at airplane altitude

    SciTech Connect

    Enomoto, R.; Chiba, J.; Ogawa, K.; Sumiyoshi, T.; Takasaki, F. ); Kifune, T. ); Matsubara, Y. ); Nishimura, J. )

    1991-12-01

    We have developed a new detector to systematically measure the cosmic-ray electron flux at airplane altitudes. We loaded a lead-glass-based electron telescope onto a commercial cargo airplane. The first experiment was carried out using the air route between Narita (Japan) and Sydney (Australia); during this flight we measured the electron flux at various altitudes and latitudes. The thresholds of the electron energies were 1, 2, and 4 GeV. The results agree with a simple estimation using one-dimensional shower theory. A comparison with a Monte Carlo calculation was made.

  14. HF Accelerated Electron Fluxes, Spectra, and Ionization

    NASA Astrophysics Data System (ADS)

    Carlson, Herbert C.; Jensen, Joseph B.

    2015-10-01

    Wave particle interactions, an essential aspect of laboratory, terrestrial, and astrophysical plasmas, have been studied for decades by transmitting high power HF radio waves into Earth's weakly ionized space plasma, to use it as a laboratory without walls. Application to HF electron acceleration remains an active area of research (Gurevich in Usp Fizicheskikh Nauk 177(11):1145-1177, 2007) today. HF electron acceleration studies began when plasma line observations proved (Carlson et al. in J Atmos Terr Phys 44:1089-1100, 1982) that high power HF radio wave-excited processes accelerated electrons not to ~eV, but instead to -100 times thermal energy (10 s of eV), as a consequence of inelastic collision effects on electron transport. Gurevich et al (J Atmos Terr Phys 47:1057-1070, 1985) quantified the theory of this transport effect. Merging experiment with theory in plasma physics and aeronomy, enabled prediction (Carlson in Adv Space Res 13:1015-1024, 1993) of creating artificial ionospheres once ~GW HF effective radiated power could be achieved. Eventual confirmation of this prediction (Pedersen et al. in Geophys Res Lett 36:L18107, 2009; Pedersen et al. in Geophys Res Lett 37:L02106, 2010; Blagoveshchenskaya et al. in Ann Geophys 27:131-145, 2009) sparked renewed interest in optical inversion to estimate electron spectra in terrestrial (Hysell et al. in J Geophys Res Space Phys 119:2038-2045, 2014) and planetary (Simon et al. in Ann Geophys 29:187-195, 2011) atmospheres. Here we present our unpublished optical data, which combined with our modeling, lead to conclusions that should meaningfully improve future estimates of the spectrum of HF accelerated electron fluxes. Photometric imaging data can significantly improve detection of emissions near ionization threshold, and confirm depth of penetration of accelerated electrons many km below the excitation altitude. Comparing observed to modeled emission altitude shows future experiments need electron density profiles

  15. Electron transport fluxes in potato plateau regime

    SciTech Connect

    Shaing, K.C.; Hazeltine, R.D.

    1997-12-01

    Electron transport fluxes in the potato plateau regime are calculated from the solutions of the drift kinetic equation and fluid equations. It is found that the bootstrap current density remains finite in the region close to the magnetic axis, although it decreases with increasing collision frequency. This finite amount of the bootstrap current in the relatively collisional regime is important in modeling tokamak startup with 100{percent} bootstrap current. {copyright} {ital 1997 American Institute of Physics.}

  16. Dependence of Electron Flux on Electron Temperature in Spacecraft Charging

    DTIC Science & Technology

    2009-01-01

    those at lower energies fall . For a given energy E, the maxi- mum of the flux curve is located at T=(2£/3). in agreement with Eq. (111. Figure 0... Bastille Day event, 2000. The spacecraft potential (negative kV) rises whenever the electron tempera- ture exceeds a critical value (from Ref. 7

  17. Electron energy flux in the solar wind.

    NASA Technical Reports Server (NTRS)

    Ogilvie, K. W.; Scudder, J. D.; Sugiura, M.

    1971-01-01

    Description of studies of electrons between 10 eV and 9.9 keV in the solar wind. The transport of energy in the rest frame of the plasma is evaluated and shown to be parallel to the interplanetary magnetic field. The presence of electrons from solar events causes this energy-flux density to exceed the heat flow due to thermal electrons. In one such event, the observations are shown to be consistent with the solar-electron observations made at higher energies. When observations are made at a point connected to the earth's bow shock by an interplanetary-field line, a comparatively large energy flux along the field toward the sun is observed, but the heat flow remains outwardly directed during this time interval. In either situation the heat flow is found to be consistent with measurements made on Vela satellites by a different method. These values, less than .01 ergs/sq cm/sec, are sufficiently low to require modifications to the Spitzer-Harm conductivity formula for use in solar-wind theories.

  18. Fermi's Large Area Telescope (LAT)

    NASA Image and Video Library

    Fermi’s Large Area Telescope (LAT) is the spacecraft’s main scientificinstrument. This animation shows a gamma ray (purple) entering the LAT,where it is converted into an electron (red) and a...

  19. Flux profile scanners for scattered high-energy electrons

    NASA Astrophysics Data System (ADS)

    Hicks, R. S.; Decowski, P.; Arroyo, C.; Breuer, M.; Celli, J.; Chudakov, E.; Kumar, K. S.; Olson, M.; Peterson, G. A.; Pope, K.; Ricci, J.; Savage, J.; Souder, P. A.

    2005-11-01

    The paper describes the design and performance of flux integrating Cherenkov scanners with air-core reflecting light guides used in a high-energy, high-flux electron scattering experiment at the Stanford Linear Accelerator Center. The scanners were highly radiation resistant and provided a good signal to background ratio leading to very good spatial resolution of the scattered electron flux profile scans.

  20. High heat flux cooling for spacecraft electronics

    SciTech Connect

    Leland, J.E.; Chow, L.C. )

    1991-01-05

    An experimental investigation of flow boiling in a curved channel has been performed to ascertain its value in electronics cooling applications. Results have been obtained for flow velocities of 1 to 5 m/s and subcooling of 0.5 to 40 K. These results were compared to those of straight channel under identical velocity and subcooling conditions. The critical heat flux of the curved channel was found to be greater than that of the straight channel. In some cases the increase was found to be marginal, however. An unexplained temperature shift in the nucleate boiling regime was experienced during some experiments. Because this shift only occurred for the first test of the day, it is thought to be related to the incipience phenomenon often experienced in pool boiling experiments. Finally, true incipience overshoot and nucleate boiling regime hysteresis were found to be negligible.

  1. Electronic and nuclear flux densities in the H2 molecule

    NASA Astrophysics Data System (ADS)

    Hermann, G.; Paulus, B.; Pérez-Torres, J. F.; Pohl, V.

    2014-05-01

    We present a theoretical study of the electronic and nuclear flux densities of a vibrating H2 molecule after an electronic excitation by a short femtosecond laser pulse. The final state, a coherent superposition of the electronic ground state X1Σg+ and the electronic excited state B1Σu+, evolves freely and permits the partition of the electronic flux density into two competing fluxes: the adiabatic and the transition flux density. The nature of the two fluxes allows us to identify two alternating dynamics of the electronic motion, occurring on the attosecond and the femtosecond time scales. In contradistinction to the adiabatic electronic flux density, the transition electronic flux density shows a dependence on the carrier-envelope phase of the laser field, encoding information of the interaction of the electrons with the electric field. Furthermore, the nuclear flux density displays multiple reversals, a quantum effect recently discovered by Manz et al. [J. Manz, J. F. Pérez-Torres, and Y. Yang, Phys. Rev. Lett. 111, 153004 (2013), 10.1103/PhysRevLett.111.153004], calling for investigation of the electronic flux density.

  2. Electron flux in molecules induced by nuclear motion

    NASA Astrophysics Data System (ADS)

    Okuyama, Michihiro; Takatsuka, Kazuo

    2009-07-01

    As a general tool for analysis of chemical reactions from the view point of electron wavepacket dynamics, electron flux within a molecule is numerically realized in terms of physically time-dependent electronic wavefunctions given by the semiclassical Ehrenfest theory. These wavefunctions are synchronized with real time motion of molecular nuclei through the nuclear kinematic coupling (nonadiabatic elements). Since the standard quantum flux gives only a null field for a real-valued electronic eigenfunction, we extend the definition of flux such that the essential information of dynamical flow of electrons can be retrieved even from adiabatic electronic wavefunctions calculated in the scheme of the so-called ab initio molecular dynamics.

  3. Exploring ISEE-3 magnetic cloud polarities with electron heat fluxes

    NASA Astrophysics Data System (ADS)

    Kahler, S. W.; Crooker, N. U.; Gosling, J. T.

    1999-06-01

    We have used solar wind electron heat fluxes to determine the magnetic polarities of the interplanetary magnetic fields (IMF) during the ISEE-3 observations in 1978-1982. That period included 14 magnetic clouds (MCs) identified by Zhang and Burlaga. The MCs have been modeled as single magnetic flux ropes, and it is generally assumed that they are magnetically closed structures with each end of the flux rope connected to the Sun. The flux rope model is valid only if the magnetic polarity of each MC does not change during the passage of ISEE-3 through the MC. We test this model with the heat flux data, using the dominant heat flux in bidirectional electron heat fluxes to determine the MC polarities. The polarity changes within at least 2, and possibly 6, of the 14 MCs, meaning that those MCs can not fit the model of a single flux rope.

  4. Constraining decaying dark matter with Fermi LAT gamma-rays

    SciTech Connect

    Zhang, Le; Sigl, Günter; Weniger, Christoph; Maccione, Luca; Redondo, Javier E-mail: christoph.weniger@desy.de E-mail: redondo@mppmm.mpg.de

    2010-06-01

    High energy electrons and positrons from decaying dark matter can produce a significant flux of gamma rays by inverse Compton off low energy photons in the interstellar radiation field. This possibility is inevitably related with the dark matter interpretation of the observed PAMELA and FERMI excesses. The aim of this paper is providing a simple and universal method to constrain dark matter models which produce electrons and positrons in their decay by using the Fermi LAT gamma-ray observations in the energy range between 0.5 GeV and 300 GeV. We provide a set of universal response functions that, once convolved with a specific dark matter model produce the desired constraints. Our response functions contain all the astrophysical inputs such as the electron propagation in the galaxy, the dark matter profile, the gamma-ray fluxes of known origin, and the Fermi LAT data. We study the uncertainties in the determination of the response functions and apply them to place constraints on some specific dark matter decay models that can well fit the positron and electron fluxes observed by PAMELA and Fermi LAT. To this end we also take into account prompt radiation from the dark matter decay. We find that with the available data decaying dark matter cannot be excluded as source of the PAMELA positron excess.

  5. Flux noise in SQUIDs: Electron versus nuclear spins

    NASA Astrophysics Data System (ADS)

    de Sousa, Rogerio; Laforest, Stephanie

    2015-03-01

    Superconducting Quantum Interference Devices (SQUIDs) are limited by intrinsic flux noise whose origin is unknown. We develop a method to accurately calculate the flux produced by spin impurities in realistic superconducting thin film wires, and show that the flux produced by each spin is much larger than anticipated by former calculations. Remarkably, the total flux noise power due to electron spins at the thin side surface of the wires is found to be of similar magnitude as the one due to electrons at the wide top surface of the wires. In addition, flux noise due to lattice nuclear spins in the bulk of the wires is found to be a sizable fraction of the total noise for some SQUID geometries. We discuss the relative importance of electron and nuclear spin species in determining the total noise power, and propose strategies to design SQUIDs with lower flux noise. We acknowledge support from the Canadian agency NSERC through its Discovery and Engage programs.

  6. Theoretical Interpretation of Pass 8 Fermi -LAT e + + e - Data

    DOE PAGES

    Di Mauro, M.; Manconi, S.; Vittino, A.; ...

    2017-08-17

    The flux of positrons and electrons (e + + e -) has been measured by the Fermi Large Area Telescope (LAT) in the energy range between 7 GeV and 2 TeV. Here, we discuss a number of interpretations of Pass 8 Fermi-LAT e sup>+ + e - spectrum, combining electron and positron emission from supernova remnants (SNRs) and pulsar wind nebulae (PWNe), or produced by the collision of cosmic rays (CRs) with the interstellar medium. We also found that the Fermi-LAT spectrum is compatible with the sum of electrons from a smooth SNR population, positrons from cataloged PWNe, and amore » secondary component. If we include in our analysis constraints from the AMS-02 positron spectrum, we obtain a slightly worse fit to the e sup>+ + e - Fermi-LAT spectrum, depending on the propagation model. As an additional scenario, we replace the smooth SNR component within 0.7 kpc with the individual sources found in Green's catalog of Galactic SNRs. We find that separate consideration of far and near sources helps to reproduce the e sup>+ + e - Fermi-LAT spectrum. However, we show that the fit degrades when the radio constraints on the positron emission from Vela SNR (which is the main contributor at high energies) are taken into account. We find that a break in the power-law injection spectrum at about 100 GeV can also reproduce the measured e sup>+ + e - spectrum and, among the CR propagation models that we consider, no reasonable break of the power-law dependence of the diffusion coefficient can modify the electron flux enough to reproduce the observed shape.« less

  7. First Results on the High Energy Cosmic Ray Electron Spectrum from Fermi Lat

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2009-01-01

    This viewgraph presentation addresses energy reconstruction, electron-hadron separation, validation of Monte Carlo with flight data and an assessment of systematic errors from the Fermi Large Area Telescope.

  8. The contribution of Fermi gamma-ray pulsars to the local flux of cosmic-ray electrons and positrons

    SciTech Connect

    Gendelev, Leo; Profumo, Stefano; Dormody, Michael E-mail: profumo@scipp.ucsc.edu

    2010-02-01

    We analyze the contribution of gamma-ray pulsars from the first Fermi-Large Area Telescope (LAT) catalogue to the local flux of cosmic-ray electrons and positrons (e{sup +}e{sup −}). We present new distance estimates for all Fermi gamma-ray pulsars, based on the measured gamma-ray flux and pulse shape. We then estimate the contribution of gamma-ray pulsars to the local e{sup +}e{sup −} flux, in the context of a simple model for the pulsar e{sup +}e{sup −} emission. We find that 10 of the Fermi pulsars potentially contribute significantly to the measured e{sup +}e{sup −} flux in the energy range between 100 GeV and 1 TeV. Of the 10 pulsars, 2 are old EGRET gamma-ray pulsars, 2 pulsars were discovered with radio ephemerides, and 6 were discovered with the Fermi pulsar blind-search campaign. We argue that known radio pulsars fall in regions of parameter space where the e{sup +}e{sup −} contribution is predicted to be typically much smaller than from those regions where Fermi-LAT pulsars exist. However, comparing the Fermi gamma-ray flux sensitivity to the regions of pulsar parameter space where a significant e{sup +}e{sup −} contribution is predicted, we find that a few known radio pulsars that have not yet been detected by Fermi can also significantly contribute to the local e{sup +}e{sup −} flux if a) they are closer than 2 kpc, and if b) they have a characteristic age on the order of one mega-year.

  9. Entanglement-assisted electron microscopy based on a flux qubit

    SciTech Connect

    Okamoto, Hiroshi; Nagatani, Yukinori

    2014-02-10

    A notorious problem in high-resolution biological electron microscopy is radiation damage caused by probe electrons. Hence, acquisition of data with minimal number of electrons is of critical importance. Quantum approaches may represent the only way to improve the resolution in this context, but all proposed schemes to date demand delicate control of the electron beam in highly unconventional electron optics. Here we propose a scheme that involves a flux qubit based on a radio-frequency superconducting quantum interference device, inserted in a transmission electron microscope. The scheme significantly improves the prospect of realizing a quantum-enhanced electron microscope for radiation-sensitive specimens.

  10. Frozen flux violation, electron demagnetization and magnetic reconnection

    SciTech Connect

    Scudder, J. D.; Karimabadi, H.; Roytershteyn, V.; Daughton, W.

    2015-10-15

    We argue that the analogue in collisionless plasma of the collisional diffusion region of magnetic reconnection is properly defined in terms of the demagnetization of the plasma electrons that enable “frozen flux” slippage to occur. This condition differs from the violation of the “frozen-in” condition, which only implies that two fluid effects are involved, rather than the necessary slippage of magnetic flux as viewed in the electron frame. Using 2D Particle In Cell (PIC) simulations, this approach properly finds the saddle point region of the flux function. Our demagnetization conditions are the dimensionless guiding center approximation expansion parameters for electrons which we show are observable and determined locally by the ratio of non-ideal electric to magnetic field strengths. Proxies for frozen flux slippage are developed that (a) are measurable on a single spacecraft, (b) are dimensionless with theoretically justified threshold values of significance, and (c) are shown in 2D simulations to recover distinctions theoretically possible with the (unmeasurable) flux function. A new potentially observable dimensionless frozen flux rate, Λ{sub Φ}, differentiates significant from anecdotal frozen flux slippage. A single spacecraft observable, ϒ, is shown with PIC simulations to be essentially proportional to the unobservable local Maxwell frozen flux rate. This relationship theoretically establishes electron demagnetization in 3D as the general cause of frozen flux slippage. In simple 2D cases with an isolated central diffusion region surrounded by separatrices, these diagnostics uniquely identify the traditional diffusion region (without confusing it with the two fluid “ion-diffusion” region) and clarify the role of the separatrices where frozen flux violations do occur but are not substantial. In the more complicated guide and asymmetric 2D cases, substantial flux slippage regions extend out along, but inside of, the preferred separatrices

  11. Relativistic electrons at geosynchronous orbit, interplanetary electron flux, and the 13-month Jovian synodic year

    NASA Technical Reports Server (NTRS)

    Christon, S. P.; Chenette, D. L.; Baker, D. N.; Moses, D.

    1989-01-01

    Results are reported from a search to determine the correlation, if any, between the temporal behaviors of 0.2-7 MeV or higher electrons at GEO (6.6 earth radii) and 6-10 MeV electrons in the interplanetary region near earth at the period of the Jovian synodic year (about 13 months). The 13-month intensity variation results from the synodic interplanetary magnetic field conection of earth to Jupiter. Direct compariosn of intensity-time flux profiles for the years 1976-1984, about 7 synodic Jovian electron seasons, shows that the intensity envelope of peak electron flux at GEO does not appear to be correlated to the observed 13 month intensity envelope of relativistic electron flux in the interplanetary region near earth. A persistent 13-month variation of GEO flux is not obvious, thus indicating that the intensity of electron flux at GEO is not directly and soley related to the intensity of Jovian electron flux near earth. It is concluded that dynamic erergization and redistribution processes in earth's magnetosphere must be invoked to produce the intensity variations of relativistic electron flux at GEO and not interplanetary magnetic field connection to Jupiter.

  12. Electron and proton flux models for Jupiter's radiation belts

    NASA Technical Reports Server (NTRS)

    Klopp, D. A.

    1972-01-01

    Estimates of the energetic particle distribution in Jupiter's radiation belts are presented and are compared with previous estimates. Mathematical expressions are developed for the equatorial electron and proton fluxes, shielded electron and proton dose rates, and radiation lifetimes of electronic circuits. It is calculated that a 1 g/sq cm aluminum shield will screen out all protons of energy less than 27.5 MeV, and a 2 g/sq cm shield will screen out protons less than 40.6 MeV. The radiation lifetimes are based on a maximum permissible dose value of 10 million rads, a value 1/2 to 1/3 of the flux at which electronic circuits begin to fail. Estimated increases in lifetimes by using a 3 x 50 orbit instead of a 3 x 3 orbit, and going from 1 to 2 g/sq cm are given.

  13. Natural and artificially injected electron fluxes near discrete auroral arcs

    NASA Technical Reports Server (NTRS)

    Wilhelm, K.

    1980-01-01

    A sounding rocket payload instrumented in order to inject and observe energetic electron fluxes in the ionospheric plasma was flown from Ft. Churchill into a bright auroral display on 9 April 1978. Measurements of one throw-away detector in three energy channels at 1.9, 4 and 8 keV are discussed in order to relate the observed electron echoes to the prevailing geophysical conditions.

  14. Measurement of neutrino flux from neutrino-electron elastic scattering

    NASA Astrophysics Data System (ADS)

    Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.; Miner ν A Collaboration

    2016-06-01

    Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ˜10 % due to uncertainties in hadron production and focusing. We have isolated a sample of 135 ±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.

  15. Measurement of neutrino flux from neutrino-electron elastic scattering

    SciTech Connect

    Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman,; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.

    2016-06-10

    Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently, a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ~10% due to uncertainties in hadron production and focusing. We also isolated a sample of 135±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Finally, our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.

  16. Measurement of neutrino flux from neutrino-electron elastic scattering

    SciTech Connect

    Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman,; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.

    2016-06-10

    Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently, a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ~10% due to uncertainties in hadron production and focusing. We also isolated a sample of 135±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Finally, our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.

  17. Measurement of neutrino flux from neutrino-electron elastic scattering

    DOE PAGES

    Park, J.; Aliaga, L.; Altinok, O.; ...

    2016-06-10

    Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently, a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ~10% due to uncertainties in hadron production and focusing. We also isolated a sample of 135±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9%more » to 6%. Finally, our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.« less

  18. Collisionality scaling of the electron heat flux in ETG turbulence

    NASA Astrophysics Data System (ADS)

    Colyer, G. J.; Schekochihin, A. A.; Parra, F. I.; Roach, C. M.; Barnes, M. A.; Ghim, Y.-c.; Dorland, W.

    2017-05-01

    In electrostatic simulations of MAST plasma at electron-gyroradius scales, using the local flux-tube gyrokinetic code GS2 with adiabatic ions, we find that the long-time saturated electron heat flux (the level most relevant to energy transport) decreases as the electron collisionality decreases. At early simulation times, the heat flux ‘quasi-saturates’ without any strong dependence on collisionality, and with the turbulence dominated by streamer-like radially elongated structures. However, the zonal fluctuation component continues to grow slowly until much later times, eventually leading to a new saturated state dominated by zonal modes and with the heat flux proportional to the collision rate, in approximate agreement with the experimentally observed collisionality scaling of the energy confinement in MAST. We outline an explanation of this effect based on a model of ETG turbulence dominated by zonal-nonzonal interactions and on an analytically derived scaling of the zonal-mode damping rate with the electron-ion collisionality. Improved energy confinement with decreasing collisionality is favourable towards the performance of future, hotter devices.

  19. Hamiltonian magnetic reconnection with parallel electron heat flux dynamics

    NASA Astrophysics Data System (ADS)

    Grasso, D.; Tassi, E.

    2015-10-01

    > We analyse, both analytically and numerically, a two-dimensional six-field fluid model for collisionless magnetic reconnection, accounting for temperature and heat flux fluctuations along the direction of the magnetic guide field. We show that the model possesses a Hamiltonian structure with a non-canonical Poisson bracket. This bracket is characterized by the presence of six infinite families of Casimirs, associated with Lagrangian invariants. This reveals that the model can be reformulated as a system of advection equations, thus generalizing previous results obtained for Hamiltonian isothermal fluid models for reconnection. Numerical simulations indicate that the presence of heat flux and temperature fluctuations yields slightly larger growth rates and similar saturated island amplitudes, with respect to the isothermal models. For values of the sonic Larmor radius much smaller than the electron skin depth, heat flux fluctuations tend to be suppressed and temperature fluctuations follow density fluctuations. Increasing the sonic Larmor radius results in an increasing fraction of magnetic energy converted into heat flux, at the expense of temperature fluctuations. In particular, heat flux fluctuations tend to become relevant along the magnetic island separatrices. The qualitative structures associated with the electron field variables are also reinterpreted in terms of the rotation of the Lagrangian invariants of the system.

  20. Geosynchronous Electron Fluxes and Chorus Generation During an MHD Substorm

    NASA Astrophysics Data System (ADS)

    Woodroffe, J. R.; Jordanova, V.; Henderson, M. G.; Welling, D. T.; Vernon, L.

    2015-12-01

    We present results from a numerical study of electron dynamics and whistler generation during an idealized substorm simulated using the Space Weather Modeling Framework. The time-dependent electric and magnetic fields from this simulated substorm are used to drive a new backwards particle tracing model, and the results from this model are used to identify the regions responsible for populating geosynchronous orbit during and after the substorm. Liouville mapping is then used to obtain electron fluxes at geosynchronous orbit as well as to assess the development of anisotropy during the earthward propagation of the electron injection.

  1. Ion and electron velocity distributions within flux transfer events

    NASA Technical Reports Server (NTRS)

    Thomsen, M. F.; Stansberry, J. A.; Bame, S. J.; Fuselier, S. A.; Gosling, J. T.

    1987-01-01

    The detailed nature of the thermal and suprathermal ion and electron distributions within magnetic flux transfer events (FTEs) is examined. Examples of both magnetosheath FTEs and magnetospheric FTEs are discussed. The detailed distributions confirm that FTEs contain a mixture of magnetosheath and magnetospheric plasmas. To lowest order, the distributions are consistent with a simple superposition of the two interpenetrating populations, with no strong interactions between them. To first order, some interesting differences appear, especially in the electron distributions, suggesting that considerable pitch angle scattering and some electron energy diffusion are also occurring. These observations should provide a useful test of analytical and numerical studies of interpenetrating plasmas.

  2. Automated Science Processing for GLAST LAT Data

    SciTech Connect

    Chiang, James

    2007-07-12

    Automated Science Processing (ASP) will be performed by the GLAST Large Area Telescope (LAT) Instrument Science Operations Center (ISOC) on data from the satellite as soon as the Level 1 data are available in the ground processing pipeline. ASP will consist of time-critical science analyses that will facilitate follow-up and multi-wavelength observations of transient sources. These analyses include refinement of gamma-ray burst (GRB) positions, timing, flux and spectral properties, off-line searches for untriggered GRBs and gamma-ray afterglows, longer time scale monitoring of a standard set of sources (AGNs, X-ray binaries), and searches for previously unknown flaring sources in the LAT band. We describe the design of ASP and its scientific products; and we show results of a prototype implementation, driven by the standard LAT data processing pipeline, as applied to simulated LAT and GBM data.

  3. Automated Science Processing for GLAST LAT Data

    SciTech Connect

    Chiang, James; Carson, Jennifer; Focke, Warren; /SLAC

    2007-10-15

    Automated Science Processing (ASP) will be performed by the GLAST Large Area Telescope (LAT) Instrument Science Operations Center (ISOC) on data from the satellite as soon as the Level 1 data are available in the ground processing pipeline. ASP will consist of time-critical science analyses that will facilitate follow-up and multi-wavelength observations of transient sources. These analyses include refinement of gamma-ray burst (GRB) positions, timing, flux and spectral properties, off-line searches for untriggered GRBs and gamma-ray afterglows, longer time scale monitoring of a standard set of sources (AGNs, X-ray binaries), and searches for previously unknown flaring sources in the LAT band. We describe the design of ASP and its scientific products; and we show results of a prototype implementation, driven by the standard LAT data processing pipeline, as applied to simulated LAT and GBM data.

  4. Observational constraints on relativistic electron dynamics: temporal evolution of electron spectra and flux isotropization

    NASA Astrophysics Data System (ADS)

    Kanekal, S. G.; Selesnick, R. S.; Baker, D. N.; Blake, J. B.

    2007-05-01

    Models of energization of electrons in the Earth's outer radiation belts invoke two classes of processes, radial transport and in-situ wave-particle interactions. Temporal evolution of electron spectra and flux isotropization during energization events provide useful observational constraints on models of electron energization. Events dominated by radial diffusion result in pancake type pitch angle distributions whereas some in-situ wave-particle energization mechanisms include pitch angle scattering leading to rapid flux isotropization. We present a survey of flux isotrpization time scales and electron spectra during relativstic electron enhancement events. We will use data collected by detectors onboard SAMPEX in low earth orbit and Polar which measures electron fluxes at higher altitude to measure flux isotropization. Electron spectra are obtained by pulse height analyzed data from the PET detector onboard SAMPEX.SAMPEX measurements cover the entire outer zone for more than a decade from mid 1992 to mid 2004 and Polar covers the time period from mid 1996 to the present.

  5. Electron Heat Flux in Pressure Balance Structures at Ulysses

    NASA Technical Reports Server (NTRS)

    Yamauchi, Yohei; Suess, Steven T.; Sakurai, Takashi; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Pressure balance structures (PBSs) are a common feature in the high-latitude solar wind near solar minimum. Rom previous studies, PBSs are believed to be remnants of coronal plumes and be related to network activity such as magnetic reconnection in the photosphere. We investigated the magnetic structures of the PBSs, applying a minimum variance analysis to Ulysses/Magnetometer data. At 2001 AGU Spring meeting, we reported that PBSs have structures like current sheets or plasmoids, and suggested that they are associated with network activity at the base of polar plumes. In this paper, we have analyzed high-energy electron data at Ulysses/SWOOPS to see whether bi-directional electron flow exists and confirm the conclusions more precisely. As a result, although most events show a typical flux directed away from the Sun, we have obtained evidence that some PBSs show bi-directional electron flux and others show an isotropic distribution of electron pitch angles. The evidence shows that plasmoids are flowing away from the Sun, changing their flow direction dynamically in a way not caused by Alfven waves. From this, we have concluded that PBSs are generated due to network activity at the base of polar plumes and their magnetic structures axe current sheets or plasmoids.

  6. Theoretical Interpretation of Pass 8 Fermi-LAT e + + e - Data

    NASA Astrophysics Data System (ADS)

    Di Mauro, M.; Manconi, S.; Vittino, A.; Donato, F.; Fornengo, N.; Baldini, L.; Bonino, R.; Di Lalla, N.; Latronico, L.; Maldera, S.; Manfreda, A.; Negro, M.; Pesce-Rollins, M.; Sgrò, C.; Spada, F.

    2017-08-01

    The flux of positrons and electrons (e + + e -) has been measured by the Fermi Large Area Telescope (LAT) in the energy range between 7 GeV and 2 TeV. We discuss a number of interpretations of Pass 8 Fermi-LAT e + + e - spectrum, combining electron and positron emission from supernova remnants (SNRs) and pulsar wind nebulae (PWNe), or produced by the collision of cosmic rays (CRs) with the interstellar medium. We find that the Fermi-LAT spectrum is compatible with the sum of electrons from a smooth SNR population, positrons from cataloged PWNe, and a secondary component. If we include in our analysis constraints from the AMS-02 positron spectrum, we obtain a slightly worse fit to the e + + e - Fermi-LAT spectrum, depending on the propagation model. As an additional scenario, we replace the smooth SNR component within 0.7 kpc with the individual sources found in Green’s catalog of Galactic SNRs. We find that separate consideration of far and near sources helps to reproduce the e + + e - Fermi-LAT spectrum. However, we show that the fit degrades when the radio constraints on the positron emission from Vela SNR (which is the main contributor at high energies) are taken into account. We find that a break in the power-law injection spectrum at about 100 GeV can also reproduce the measured e + + e - spectrum and, among the CR propagation models that we consider, no reasonable break of the power-law dependence of the diffusion coefficient can modify the electron flux enough to reproduce the observed shape.

  7. Characteristics of heat flux and electromagnetic electron-cyclotron instabilities driven by solar wind electrons

    NASA Astrophysics Data System (ADS)

    Saeed, Sundas; Sarfraz, M.; Yoon, P. H.; Qureshi, M. N. S.

    2017-01-01

    In-situ observations reveal the existence of electron velocity distribution function in the solar wind, where the net distribution can be modeled by a combination of core, halo and strahl. These components often possess a relative drift and with respective temperature anisotropies. The relative drift between the core and halo components leads to heat flux (HF) instability, while temperature anisotropies drive electromagnetic electron-cyclotron (EMEC) instability. These instabilities have been separately studied in the literature, but for the first time, the present study combines both unstable modes in the presence of two free energy sources, namely, excessive parallel pressure and excessive perpendicular temperature. Heat flux instability (which is a left-hand circularly polarized mode) is effectively similar to electron firehose instability, except that the free energy is provided by net relative drift among two component electrons in the background of protons. The heat flux instability is discussed here along with (the right-hand polarized) EMEC instability driven by temperature anisotropy. The unstable heat flux mode is conventionally termed the "whistler" heat flux instability, but it is actually polarized in the opposite sense to the whistler wave. Electromagnetic electron-cyclotron mode, on the other hand, reduces to the proper whistler wave in the absence of free energy source. The present combined analysis clarifies the polarization characteristics of these two modes in an unambiguous manner.

  8. Chemical potential and reaction electronic flux in symmetry controlled reactions.

    PubMed

    Vogt-Geisse, Stefan; Toro-Labbé, Alejandro

    2016-07-15

    In symmetry controlled reactions, orbital degeneracies among orbitals of different symmetries can occur along a reaction coordinate. In such case Koopmans' theorem and the finite difference approximation provide a chemical potential profile with nondifferentiable points. This results in an ill-defined reaction electronic flux (REF) profile, since it is defined as the derivative of the chemical potential with respect to the reaction coordinate. To overcome this deficiency, we propose a new way for the calculation of the chemical potential based on a many orbital approach, suitable for reactions in which symmetry is preserved. This new approach gives rise to a new descriptor: symmetry adapted chemical potential (SA-CP), which is the chemical potential corresponding to a given irreducible representation of a symmetry group. A corresponding symmetry adapted reaction electronic flux (SA-REF) is also obtained. Using this approach smooth chemical potential profiles and well defined REFs are achieved. An application of SA-CP and SA-REF is presented by studying the Cs enol-keto tautomerization of thioformic acid. Two SA-REFs are obtained, JA'(ξ) and JA'' (ξ). It is found that the tautomerization proceeds via an in-plane delocalized 3-center 4-electron O-H-S hypervalent bond which is predicted to exist only in the transition state (TS) region. © 2016 Wiley Periodicals, Inc.

  9. Automatic solar image motion measurements. [electronic disk flux monitoring

    NASA Technical Reports Server (NTRS)

    Colgate, S. A.; Moore, E. P.

    1975-01-01

    The solar seeing image motion has been monitored electronically and absolutely with a 25 cm telescope at three sites along the ridge at the southern end of the Magdalena Mountains west of Socorro, New Mexico. The uncorrelated component of the variations of the optical flux from two points at opposite limbs of the solar disk was continually monitored in 3 frequencies centered at 0.3, 3 and 30 Hz. The frequency band of maximum signal centered at 3 Hz showed the average absolute value of image motion to be somewhat less than 2sec. The observer estimates of combined blurring and image motion were well correlated with electronically measured image motion, but the observer estimates gave a factor 2 larger value.

  10. Polar cap auroral electron fluxes observed with Isis 1

    NASA Technical Reports Server (NTRS)

    Winningham, J. D.; Heikkila, W. J.

    1974-01-01

    Three types of auroral particle precipitation have been observed over the polar caps, well inside the auroral oval, by means of the soft particle spectrometer on the Isis 1 satellite. The first type is a uniform, very soft (about 100 eV) electron 'polar rain' over the entire polar cap; this may well be present with very weak intensity at all times, but it is markedly enhanced during worldwide geomagnetic storms. A second type of precipitation is a structured flux of electrons with energies near 1 keV, suggestive of localized 'polar showers'; it seems likely that these are the cause of the sun-aligned auroral arcs that have been observed during moderately quiet conditions. During periods of intense magnetic disturbance this precipitation can become very intense and exhibit a characteristic pattern that we have come to call a 'polar squall'.

  11. Polar cap auroral electron fluxes observed with Isis 1

    NASA Technical Reports Server (NTRS)

    Winningham, J. D.; Heikkila, W. J.

    1974-01-01

    Three types of auroral particle precipitation have been observed over the polar caps, well inside the auroral oval, by means of the soft particle spectrometer on the Isis 1 satellite. The first type is a uniform, very soft (about 100 eV) electron 'polar rain' over the entire polar cap; this may well be present with very weak intensity at all times, but it is markedly enhanced during worldwide geomagnetic storms. A second type of precipitation is a structured flux of electrons with energies near 1 keV, suggestive of localized 'polar showers'; it seems likely that these are the cause of the sun-aligned auroral arcs that have been observed during moderately quiet conditions. During periods of intense magnetic disturbance this precipitation can become very intense and exhibit a characteristic pattern that we have come to call a 'polar squall'.

  12. Electron flux models for different energies at geostationary orbit

    NASA Astrophysics Data System (ADS)

    Boynton, R. J.; Balikhin, M. A.; Sibeck, D. G.; Walker, S. N.; Billings, S. A.; Ganushkina, N.

    2016-10-01

    Forecast models were derived for energetic electrons at all energy ranges sampled by the third-generation Geostationary Operational Environmental Satellites (GOES). These models were based on Multi-Input Single-Output Nonlinear Autoregressive Moving Average with Exogenous inputs methodologies. The model inputs include the solar wind velocity, density and pressure, the fraction of time that the interplanetary magnetic field (IMF) was southward, the IMF contribution of a solar wind-magnetosphere coupling function proposed by Boynton et al. (2011b), and the Dst index. As such, this study has deduced five new 1 h resolution models for the low-energy electrons measured by GOES (30-50 keV, 50-100 keV, 100-200 keV, 200-350 keV, and 350-600 keV) and extended the existing >800 keV and >2 MeV Geostationary Earth Orbit electron fluxes models to forecast at a 1 h resolution. All of these models were shown to provide accurate forecasts, with prediction efficiencies ranging between 66.9% and 82.3%.

  13. Electron Flux Models for Different Energies at Geostationary Orbit

    NASA Technical Reports Server (NTRS)

    Boynton, R. J.; Balikhin, M. A.; Sibeck, D. G.; Walker, S. N.; Billings, S. A.; Ganushkina, N.

    2016-01-01

    Forecast models were derived for energetic electrons at all energy ranges sampled by the third-generation Geostationary Operational Environmental Satellites (GOES). These models were based on Multi-Input Single-Output Nonlinear Autoregressive Moving Average with Exogenous inputs methodologies. The model inputs include the solar wind velocity, density and pressure, the fraction of time that the interplanetary magnetic field (IMF) was southward, the IMF contribution of a solar wind-magnetosphere coupling function proposed by Boynton et al. (2011b), and the Dst index. As such, this study has deduced five new 1 h resolution models for the low-energy electrons measured by GOES (30-50 keV, 50-100 keV, 100-200 keV, 200-350 keV, and 350-600 keV) and extended the existing >800 keV and >2 MeV Geostationary Earth Orbit electron fluxes models to forecast at a 1 h resolution. All of these models were shown to provide accurate forecasts, with prediction efficiencies ranging between 66.9% and 82.3%.

  14. Counterstreaming electrons in small interplanetary magnetic flux ropes

    NASA Astrophysics Data System (ADS)

    Feng, H. Q.; Zhao, G. Q.; Wang, J. M.

    2015-12-01

    Small interplanetary magnetic flux ropes (SIMFRs) are commonly observed by spacecraft at 1 AU, and their origin still remains disputed. We investigated the counterstreaming suprathermal electron (CSE) signatures of 106 SIMFRs measured by Wind during 1995-2005. We found that 79 (75%) of the 106 flux ropes contain CSEs, and the percentages of counterstreaming vary from 8% to 98%, with a mean value of 51%. CSEs are often observed in magnetic clouds (MCs), and this indicates these MCs are still attached to the Sun at both ends. CSEs are also related to heliospheric current sheets (HCSs) and the Earth's bow shock. We divided the SIMFRs into two categories: The first category is far from HCSs, and the second category is in the vicinity of HCSs. The first category has 57 SIMFRs, and only 7 of 57 ropes have no CSEs. This ratio is similar to that of MCs. The second category has 49 SIMFRs; however, 20 of the 49 events have no CSEs. This ratio is larger than that of MCs. These two categories have different origins. One category originates from the solar corona, and most ropes are still connected to the Sun at both ends. The other category is formed near HCSs in the interplanetary space.

  15. Localized electrons on a lattice with incommensurate magnetic flux

    NASA Astrophysics Data System (ADS)

    Fishman, Shmuel; Shapir, Yonathan; Wang, Xiang-Rong

    1992-11-01

    The magnetic-field effects on lattice wave functions of Hofstadter electrons strongly localized at boundaries are studied analytically and numerically. The exponential decay of the wave function is modulated by a field-dependent amplitude J(t)=tprodt-1r=02 cos(παr), where α is the magnetic flux per plaquette (in units of a flux quantum) and t is the distance from the boundary (in units of the lattice spacing). The behavior of ||J(t)|| is found to depend sensitively on the value of α. While for rational values α=p/q the envelope of J(t) increases as 2t/q, the behavior for α irrational (q-->∞) is erratic with an aperiodic structure which drastically changes with α. For algebraic α it is found that J(t) increases as a power law tβ(α) while it grows faster (presumably as tβ(α)lnt) for transcendental α. This is very different from the growth rate J(t)~e√t that is typical for cosines with random phases. The theoretical analysis is extended to products of the type Jν(t)=tprodt-1r=02 cos(παrν) with ν>0. Different behavior of Jν(t) is found in various regimes of ν. It changes from periodic for small ν to randomlike for large ν.

  16. Extreme relativistic electron fluxes at geosynchronous orbit: Analysis of GOES E > 2 MeV electrons

    NASA Astrophysics Data System (ADS)

    Meredith, Nigel P.; Horne, Richard B.; Isles, John D.; Rodriguez, Juan V.

    2015-03-01

    Relativistic electrons (E > 1 MeV) cause internal charging on satellites and are an important space weather hazard. A key requirement in space weather research concerns extreme events and knowledge of the largest flux expected to be encountered over the lifetime of a satellite mission. This is interesting both from scientific and practical points of view since satellite operators, engineers, and the insurance industry need this information to better evaluate the effects of extreme events on their spacecraft. Here we conduct an extreme value analysis of daily averaged E > 2 MeV electron fluxes from the Geostationary Operational Environmental Satellites (GOES) during the 19.5 year period from 1 January 1995 to 30 June 2014. We find that the daily averaged flux measured at GOES West is typically a factor of about 2.5 higher than that measured at GOES East, and we conduct independent analyses for these two locations. The 1 in 10, 1 in 50, and 1 in 100 year daily averaged E > 2 MeV electron fluxes at GOES West are 1.84 ×105, 5.00 ×105, and 7.68 ×105 cm-2 s-1 sr-1, respectively. The corresponding fluxes at GOES East are 6.53 ×104, 1.98 ×105, and 3.25 ×105 cm-2 s-1 sr-1, respectively. The largest fluxes seen during the 19.5 year period on 29 July 2004 were particularly extreme and were seen by satellites at GOES West and GOES East. The extreme value analysis suggests that this event was a 1 in 50 year event.

  17. A determination of the gamma-ray flux and photon spectral index distributions of blazars from the Fermi-LAT 3LAC

    NASA Astrophysics Data System (ADS)

    Singal, J.

    2015-11-01

    We present a determination of the distributions of gamma-ray photon flux - the so-called LogN-LogS relation - and photon spectral index for blazars, based on the third extragalactic source catalogue of the Fermi Gamma-ray Space Telescope's Large Area Telescope, and considering the photon energy range from 100 MeV to 100 GeV. The data set consists of the 774 blazars in the so-called Clean sample detected with a greater than approximately 7σ detection threshold and located above ±20° Galactic latitude. We use non-parametric methods verified in previous works to reconstruct the intrinsic distributions from the observed ones which account for the data truncations introduced by observational bias and includes the effects of the possible correlation between the flux and photon index. The intrinsic flux distribution can be represented by a broken power law with a high-flux power-law index of -2.43 ± 0.08 and a low-flux power-law index of -1.87 ± 0.10. The intrinsic photon index distribution can be represented by a Gaussian with mean of 2.62 ± 0.05 and width of 0.17 ± 0.02. We also report the intrinsic distributions for the subpopulations of BL Lac and FSRQ (Flat Spectrum Radio Quasar)-type blazars separately and these differ substantially. We then estimate the contribution of FSRQs and BL Lacs to the diffuse extragalactic gamma-ray background radiation. Under the simplistic assumption that the flux distributions probed in this analysis continue to arbitrary low flux, we calculate that the best-fitting contribution of FSRQs is 35 per cent and BL Lacs 17 per cent of the total gamma-ray output of the Universe in this energy range.

  18. In Situ Measurement of Energetic Electron Fluxes Inside Thunderclouds

    NASA Astrophysics Data System (ADS)

    Arabshahi, S.; Vodopiyanov, I. B.; Dwyer, J. R.; Rassoul, H.

    2013-12-01

    It is now well established that high-energy radiation is routinely produced by thunderclouds and lightning. This radiation is in the form of x-rays and gamma-rays with timescales ranging from sub-microsecond (x-rays associated with lightning leaders), to sub-millisecond (Terrestrial Gamma-ray Flashes), to minute long glows (Gamma-ray Glows from thunderclouds seen on the ground and in or near the cloud by aircrafts and balloons). It is generally accepted that these emissions originate from bremsstrahlung interactions of relativistic runaway electrons with air, which can be accelerated in the thundercloud/lightning electric fields and gain up to multi-MeV energies. However, the exact physical details of the mechanism that produces these runaway electrons are still unknown. In order to better understand the source of energetic radiation inside thunderclouds, we have begun a campaign of balloon-borne instruments to directly measure the flux of energetic electrons inside thunderclouds. In the current configuration, each balloon carries Geiger counters to record the energetic particles. Geiger counters are well suited for directly measuring energetic electrons and positrons and have the advantage of being lightweight and dependable. Due to the nature of the thunderstorm environment, the campaign has many design, communication, and safety challenges. In this presentation we will report on the status of the campaign and some of the physical insights gained from the data collected by our instruments. This work was supported in part by the NASA grant NNX12A002H and by DARPA grant HR0011-1-10-1-0061.

  19. Balloon-borne measurement of energetic electron fluxes inside thunderclouds

    NASA Astrophysics Data System (ADS)

    Arabshahi, Shahab; Vodopiyanov, Igor; Dwyer, Joseph; Rassoul, Hamid

    2014-05-01

    High-energy radiation is routinely produced by thunderclouds and lightning. This radiation is in the form of x-rays and gamma-rays with timescales ranging from sub-microsecond (x-rays associated with lightning leaders), to sub-millisecond (Terrestrial Gamma-ray Flashes), to minute long glows (Gamma-ray Glows from thunderclouds seen on the ground and in or near the cloud by aircrafts and balloons). It is generally accepted that these emissions originate from bremsstrahlung interactions of relativistic runaway electrons with air, which can be accelerated in the thundercloud/lightning electric fields and gain up to multi-MeV energies. However, the exact physical details of the mechanism that produces these runaway electrons are still unknown. In order to better understand the source of energetic radiation inside thunderclouds, we have begun a campaign of balloon-borne instruments to directly measure the flux of energetic electrons inside thunderclouds. In the current configuration, each balloon carries Geiger counters to record the energetic particles. Geiger counters are well suited for directly measuring energetic electrons and positrons and have the advantage of being lightweight and dependable. We transmit data at 900MHz, ISM band, with 115.2 kb/s transmission rate. This would provide us a high resolution radiation profile over a relatively large distance. Due to the nature of the thunderstorm environment, the campaign has many design, communication, and safety challenges. In this presentation we will report on the status of the campaign and some of the physical insights gained from the data collected by our instruments. This work was supported in part by the NASA grant NNX12A002H and by DARPA grant HR0011-1-10-1-0061.

  20. Beta electron fluxes inside a magnetic plasma cavern: Calculation and comparison with experiment

    NASA Astrophysics Data System (ADS)

    Stupitskii, E. L.; Smirnov, E. V.; Kulikova, N. A.

    2010-12-01

    We study the possibility of electrostatic blanking of beta electrons in the expanding spherical blob of a radioactive plasma in a rarefied ionosphere. From numerical studies on the dynamics of beta electrons departing a cavern, we obtain the form of a function that determines the portion of departing electrons and calculate the flux density of beta electrons inside the cavern in relation to the Starfish Prime nuclear blast. We show that the flux density of electrons in geomagnetic flux tubes and inside the cavern depend on a correct allowance for the quantity of beta electrons returning to the cavern. On the basis of a physical analysis, we determine the approximate criterion for the return of electrons from a geomagnetic flux tube to the cavern. We compare calculation results in terms of the flux density of beta electrons inside the cavern with the recently published experimental results from operation Starfish Prime.

  1. Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV

    SciTech Connect

    Ackermann, M.

    2010-11-01

    We present the results of our analysis of cosmic-ray electrons using about 8 × 106 electron candidates detected in the first 12 months on-orbit by the Fermi Large Area Telescope. This work extends our previously published cosmic-ray electron spectrum down to 7 GeV, giving a spectral range of approximately 2.5 decades up to 1 TeV. We describe in detail the analysis and its validation using beam-test and on-orbit data. In addition, we describe the spectrum measured via a subset of events selected for the best energy resolution as a cross-check on the measurement using the full event sample. Our electron spectrum can be described with a power law ∝ E - 3.08 ± 0.05 with no prominent spectral features within systematic uncertainties. Within the limits of our uncertainties, we can accommodate a slight spectral hardening at around 100 GeV and a slight softening above 500 GeV.

  2. Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV

    DOE PAGES

    Ackermann, M.

    2010-11-01

    We present the results of our analysis of cosmic-ray electrons using about 8 × 106 electron candidates detected in the first 12 months on-orbit by the Fermi Large Area Telescope. This work extends our previously published cosmic-ray electron spectrum down to 7 GeV, giving a spectral range of approximately 2.5 decades up to 1 TeV. We describe in detail the analysis and its validation using beam-test and on-orbit data. In addition, we describe the spectrum measured via a subset of events selected for the best energy resolution as a cross-check on the measurement using the full event sample. Our electronmore » spectrum can be described with a power law ∝ E - 3.08 ± 0.05 with no prominent spectral features within systematic uncertainties. Within the limits of our uncertainties, we can accommodate a slight spectral hardening at around 100 GeV and a slight softening above 500 GeV.« less

  3. A survey of superthermal electron flux depressions, or "electron holes," within the illuminated Martian induced magnetosphere

    NASA Astrophysics Data System (ADS)

    Hall, B. E. S.; Lester, M.; Nichols, J. D.; Sánchez-Cano, B.; Andrews, D. J.; Opgenoorth, H. J.; Fränz, M.

    2016-05-01

    Since Mars lacks a global intrinsic magnetic field, the solar wind interacts directly with the Martian upper atmosphere and ionosphere. The presence of localized intense remnant crustal magnetic fields adds to this interaction, making the Martian plasma system a unique environment within the solar system. Rapid reductions in the electron flux, referred to as "electron holes," occur within the Martian induced magnetosphere (IM). We present a statistical analysis of this phenomenon identified from proxy measurements of the electron flux derived from measurements by the Analyser of Space Plasmas and Energetic Neutral Atoms Electron Spectrometer experiment on board the Mars Express (MEX) spacecraft. The study is completed for the period of 9 February 2004 to 9 May 2014. Electron holes are observed within the IM in more than 56% of MEX orbits during this study period, occurring predominantly at altitudes less than 1300 km, with the majority in the negative X Mars-Centric Solar Orbital direction. The spatial distribution above the surface of Mars is observed to bear close resemblance to that of the crustal magnetic fields as predicted by the Cain et al. magnetic field model, suggesting that they play an important role in the formation of these phenomena.

  4. Plasmaspheric Electron Densities and Plasmashere-Ionosphere Coupling Fluxes

    NASA Astrophysics Data System (ADS)

    Lichtenberger, Janos; Cherneva, Nina; Shevtsov, Boris; Sannikov, Dmitry; Ferencz, Csaba; Koronczay, David

    The Automatic Whistler Detector and Analyzer Network (AWDANet) is able to detect and analyze whistlers in quasi-realtime and can provide equatorial electron density data. The plasmaspheric electron densities and ionosphere-plasmasphere coupling fluxes are key parameters for plasmasphere models in Space Weather related investigations, particularly in modeling charged particle accelerations and losses in Radiation Belts. The global AWDANet [1] detects millions of whistlers in a year. The system has been recently completed with automatic analyzer capability in PLASMON (http://plasmon.elte.hu) project. It is based on a recently developed whistler inversion model [2], that opened the way for an automated process of whistler analysis, not only for single whistler events but for complex analysis of multiple-path propagation whistler groups [3]. In this paper we present the results of quasi-real-time runs processing whistlers from quiet and disturb periods from Karymshina station (Kamchatka, Russia). Refilling rates, that are not yet known in details are also presented for the various periods. 1.Lichtenberger, J., C. Ferencz, L. Bodnár, D. Hamar, and P. Steinbach (2008), Automatic whistler detector and analyzer system: Automatic whistler detector, J. Geophys. Res., 113, A12201, doi:10.1029/2008JA013467. 2. Lichtenberger, J. (2009), A new whistler inversion method, J. Geophys. Res., 114, A07222, doi:10.1029/2008JA013799. 3. Lichtenberger, J., C. Ferencz, D. Hamar, P. Steinbach, C. J. Rodger, M. A. Clilverd, and A. B. Collier (2010), Automatic Whistler Detector and Analyzer system: Implementation of the analyzer algorithm, J. Geophys. Res., 115, A12214, doi:10.1029/2010JA015931.

  5. Chandra and Swift Observations of Unidentified Fermi-LAT Objects

    NASA Astrophysics Data System (ADS)

    Donato, Davide; Cheung, T.; Gehrels, N.

    2010-03-01

    In the last year we targeted some of the unidentified Fermi-LAT objects (UFOs) at high Galactic latitude with Chandra and Swift in order to determine the basic properties (positions, fluxes, hardness ratios) of all X-ray sources within the Fermi-LAT localization circles. These satellites enable us to detect the X-ray conterparts with a flux limit that is at least an order of magnitude lower than achieved in extant RASS data and to further follow-up at other wavelengths, with the ultimate goal to reveal the nature of these enigmatic gamma-ray sources. Here we present the results obtained with 5 Chandra pointings of high Galactic latitude UFOs in the Fermi-LAT 3-months bright source list. The association of detected X-ray sources within the improved 11-months Fermi-LAT localization circles with available optical and radio observations is discussed.

  6. Comparison between triangulated auroral altitude and precipitating electron energy flux

    NASA Astrophysics Data System (ADS)

    Sangalli, L.; Partamies, N. J.; Gustavsson, B.

    2012-12-01

    The MIRACLE network monitors auroral activity in the Fennoscandian sector of Europe. Network stations cover the range of 55° to 57° magnetic latitude North and span two hours in magnetic local time. Some of the MIRACLE network stations include digital all-sky cameras (ASC) with overlapping field-of-views at the latitude aurora occurs. The ASCs in this network operate at three different wavelengths: 427.8 nm (blue line), 557.7 nm (green line) and 630.0 nm (red line). These wavelengths are selected using narrow band filters. Red and blue lines images are recorded once per minute and green line images every 20 s. On January 31, 2001 multiple discrete arcs were observed at the zenith of the ASC located in Muonio (67.9° N, 23.6° E) and were visible in other stations. The peak auroral emission is estimated using triangulation between pairs of stations and compared with precipitating electron energy fluxes inverted from ASC images and measured in situ on the DMSP satellite.

  7. Comparison between triangulated auroral altitude and precipitating electron energy flux

    NASA Astrophysics Data System (ADS)

    Sangalli, L.; Partamies, N. J.; Gustavsson, B.

    2013-12-01

    The MIRACLE network monitors auroral activity in the Fennoscandian sector of Europe. Network stations cover the range of 55° to 57° magnetic latitude North and span two hours in magnetic local time. Some of the MIRACLE network stations include digital all-sky cameras (ASC) with overlapping field-of-views at the latitude aurora occurs. The ASCs in this network operate at three different wavelengths: 427.8 nm (blue line), 557.7 nm (green line) and 630.0 nm (red line). These wavelengths are selected using narrow band filters. Red and blue lines images are recorded once per minute and green line images every 20 s. On January 31, 2001 multiple discrete arcs were observed at the zenith of the ASC located in Muonio (67.9° N, 23.6° E) and were visible in other stations. The peak auroral emission is estimated using triangulation between pairs of stations and compared with precipitating electron energy fluxes inverted from ASC images and measured in situ on the DMSP satellite.

  8. Identifying Loss Mechanisms Responsible for the Rapid Depletion of Outer Radiation Belt Electron Flux

    NASA Astrophysics Data System (ADS)

    Green, J. C.; Onsager, T. G.; O'Brien, T.; Fraser, B. J.

    2004-12-01

    Since the discovery of earth's radiation belts researchers have sought to explain and predict the changing relativistic electron flux levels in the outer belt. This goal has proved a perplexing challenge because, surprisingly, flux levels do not always rise as energy input from the solar wind increases during active periods such as geomagnetic storms [Reeves et al., 2003;O'Brien et al., 2001]. The erratic response of the radiation belt electrons to geomagnetic activity suggests that flux levels are set by a teetering struggle between acceleration and loss. Thus, to predict flux variations, both processes must be understood. Some acceleration mechanisms have been proposed and tested resulting in incremental progress, but still little is known about how relativistic electrons are removed from the magnetosphere. We investigate how relativistic electrons are lost from the outer radiation belt using a superposed epoch analysis of electron flux decrease events identified in multi-satellite data [Onsager et al., 2002; Green et al., 2004]. More specifically, we test three mechanisms proposed to explain the flux reductions: adiabatic motion in response to a changing magnetic field topology, drift out the magnetopause boundary, and scattering into the atmosphere. The superposed study shows that the magnetic field becomes temporarily stretched at dusk suggesting that adiabatic electron motion might contribute to the initial flux reduction; however, the electron flux does not recover when the magnetic field recovers, indicating that true loss from the magnetosphere occurs. Magnetopause encounters should similarly affect both high energy protons and electrons; however, no concurrent reduction of proton flux is observed implying that this mechanism is not active. Low altitude observations show increased electron flux in the loss cone suggesting that scattering to the atmosphere is the cause the flux depletions. We investigate possible causes of the increased scattering including

  9. Auroral electron precipitation and flux tube erosion in Titan’s upper atmosphere

    NASA Astrophysics Data System (ADS)

    Snowden, D.; Yelle, R. V.; Galand, M.; Coates, A. J.; Wellbrock, A.; Jones, G. H.; Lavvas, P.

    2013-09-01

    Cassini dasta shows that Titan’s atmosphere strongly depletes the electron content in Saturn’s flux tubes, producing features known as electron bite-outs, which indicate that the flux of auroral electrons decreases over time. To understand this process we have developed a time-dependent two-stream model, which uses field line geometries and drift paths calculated by a three-dimensional multi-fluid model of Titan’s plasma interaction. The boundary conditions of the model account for the time-dependent reduction or increase in electron flux along Saturn’s magnetic field lines because of the loss or production of electrons in Titan’s atmosphere. The modification of the auroral electron flux depends on the electron bounce period in Saturn’s outer magnetosphere; therefore, we also calculate electron bounce periods along several Kronian field lines accounting for both the magnetic mirroring force and the field-aligned electric potential in Saturn’s plasma sheet. We use the time-dependent two-stream model to calculate how the reduction in the auroral electron flux affects electron impact ionization and energy deposition rates in Titan’s upper atmosphere. We find that the flux of higher energy (>50 eV) electrons entering Titan’s atmosphere is strongly reduced over time, resulting in smaller ionization and energy deposition rates below ∼1300 km altitude. Finally, we show that sample spectrograms produced from our calculations are consistent with CAPS-ELS data.

  10. Sawtooth oscillations in the flux of runaway electrons to the PLT limiter

    SciTech Connect

    Barnes, C.W.; Strachan, J.D.

    1982-03-01

    Increased fluxes of runaway electrons at the PLT limiter are observed in the few milliseconds following internal disruptions. These fluxes have an inverted (outside) sawtooth character. The time for the flux to reach a maximum after the disruption has been studied as a function of the plasma parameters for thousands of PLT discharges. One interpretation is that this delay represents the time for a perturbation to the runaway electron population to travel from the q = 1 region to the plasma boundary. These times are approx. 10/sup -1/ of the electron thermal confinement times and increase with the plasma electron density.

  11. Nightside electron flux measurements at Mars by the Phobos-2 HARP instrument

    NASA Technical Reports Server (NTRS)

    Shutte, N.; Gringauz, K.; Kiraly, P.; Kotova, G.; Nagy, A. F.; Rosenbauer, H.; Szego, K.; Verigin, M.

    1995-01-01

    All the available nightside electron data obtained during circular orbits at Mars from the Phobos-2 Hyperbolic Retarded Potential Analyzer (HARP) instrument have been examined in detail and are summarized in this paper. An electron flux component with energies exceeding that of the unperturbed solar wind was observed inside the magnetosheath, indicating the presence of acceleration mechanism(s). The character of the electron fluxes measured in the magnetotail cannot be classified in any simple manner, however, there is a correlation between the electron fluxes measured well inside this region and the unperturbed solar wind ram pressure.

  12. Selective four electron reduction of O2 by an iron porphyrin electrocatalyst under fast and slow electron fluxes.

    PubMed

    Samanta, Subhra; Sengupta, Kushal; Mittra, Kaustuv; Bandyopadhyay, Sabyasachi; Dey, Abhishek

    2012-08-07

    An iron porphyrin catalyst with four electron donor groups is reported. The porphyrin ligand bears a distal hydrogen bonding pocket which inverts the normal axial ligand binding selectivity exhibited by porphyrins bearing sterically crowded distal structures. This catalyst specifically reduces O(2) by four electrons under both fast and slow electron fluxes at pH 7.

  13. Energetic electron spectra and flux isotropization during different phases of solar cycle

    NASA Astrophysics Data System (ADS)

    Kanekal, S. G.; Selesnick, R. S.; Baker, D. N.; Blake, J. B.

    2006-12-01

    We will report here on the measurements of electron spectra and flux isotropization during electron energization events. We will present the results of investigating the dependence of electron spectra and flux isotropization upon solar cycle phase. It is well known that high speed solar wind streams dominate during the descending phase of the solar cycle whereas coronal mass ejections are the dominant driver of the magnetosphere during the ascending phase. Temporal evolution of electron spectra and flux isotropization may be important discriminators of models of electron energization in the Earth's outer zone. For example, radial diffusion preferentially energizes electrons of large equatorial pitch angles whereas some in-situ wave-particle energization mechanisms include concomittant pitch angle scattering leading to rapid flux isotropization. The systematics of electron energization due to different drivers may shed light upon the underlying physical processes. We will use data collected by detectors onboard SAMPEX in low earth orbit and Polar which measures electron fluxes at higher altitude to characterize flux isotropization. Electron spectra are obtained by the use of pulse height analyzed data from the PET detector onboard SAMPEX. We will use global field models such as the Tsyaganenko-04 model, to calculate thegeneralized L parameter during geomagnetically disturbed times. SAMPEX measurements cover the entire outer zone for more than a decade from mid 1992 to mid 2004 and Polar covers the time period from mid 1996 to the present.

  14. Influence of the crustal magnetic field on the Mars aurora electron flux and UV brightness

    NASA Astrophysics Data System (ADS)

    Bisikalo, D. V.; Shematovich, V. I.; Gérard, J.-C.; Hubert, B.

    2017-01-01

    Observations with the SPICAM instrument on board Mars Express have shown the occasional presence of localized ultraviolet nightside emissions associated with enhanced energetic electron fluxes. These features generally occur in regions with significant radial crustal magnetic field. We use a Monte-Carlo electron transport model to investigate the role of the magnetic field on the downward and upward electron fluxes, the brightness and the emitted power of auroral emissions. Simulations based on an ASPERA-3 measured auroral electron precipitation indicate that magnetic mirroring leads to an intensification of the energy flux carried by upward moving electrons- from about 20% in the absence of crustal magnetic field up to 33-78% when magnetic field is included depending on magnetic field topology. Conservation of the particle flux in a flux tube implies that the presence of the B-field does not appreciably modify the emission rate profiles for an initially isotropic pitch angle distribution. However, we find that crustal magnetic field results in increase of the upward electron flux, and, consequently, in reduction of the total auroral brightness for given energy flux of precipitating electrons.

  15. Prediction of MeV electron fluxes throughout the outer radiation belt using multivariate autoregressive models

    DOE PAGES

    Sakaguchi, Kaori; Nagatsuma, Tsutomu; Reeves, Geoffrey D.; ...

    2015-12-22

    The Van Allen radiation belts surrounding the Earth are filled with MeV-energy electrons. This region poses ionizing radiation risks for spacecraft that operate within it, including those in geostationary orbit (GEO) and medium Earth orbit. In order to provide alerts of electron flux enhancements, 16 prediction models of the electron log-flux variation throughout the equatorial outer radiation belt as a function of the McIlwain L parameter were developed using the multivariate autoregressive model and Kalman filter. Measurements of omnidirectional 2.3 MeV electron flux from the Van Allen Probes mission as well as >2 MeV electrons from the GOES 15 spacecraftmore » were used as the predictors. Furthermore, we selected model explanatory parameters from solar wind parameters, the electron log-flux at GEO, and geomagnetic indices. For the innermost region of the outer radiation belt, the electron flux is best predicted by using the Dst index as the sole input parameter. For the central to outermost regions, at L≥4.8 and L ≥5.6, the electron flux is predicted most accurately by including also the solar wind velocity and then the dynamic pressure, respectively. The Dst index is the best overall single parameter for predicting at 3 ≤ L ≤ 6, while for the GEO flux prediction, the KP index is better than Dst. Finally, a test calculation demonstrates that the model successfully predicts the timing and location of the flux maximum as much as 2 days in advance and that the electron flux decreases faster with time at higher L values, both model features consistent with the actually observed behavior.« less

  16. Prediction of MeV electron fluxes throughout the outer radiation belt using multivariate autoregressive models

    NASA Astrophysics Data System (ADS)

    Sakaguchi, Kaori; Nagatsuma, Tsutomu; Reeves, Geoffrey D.; Spence, Harlan E.

    2015-12-01

    The Van Allen radiation belts surrounding the Earth are filled with MeV-energy electrons. This region poses ionizing radiation risks for spacecraft that operate within it, including those in geostationary orbit (GEO) and medium Earth orbit. To provide alerts of electron flux enhancements, 16 prediction models of the electron log-flux variation throughout the equatorial outer radiation belt as a function of the McIlwain L parameter were developed using the multivariate autoregressive model and Kalman filter. Measurements of omnidirectional 2.3 MeV electron flux from the Van Allen Probes mission as well as >2 MeV electrons from the GOES 15 spacecraft were used as the predictors. Model explanatory parameters were selected from solar wind parameters, the electron log-flux at GEO, and geomagnetic indices. For the innermost region of the outer radiation belt, the electron flux is best predicted by using the Dst index as the sole input parameter. For the central to outermost regions, at L ≧ 4.8 and L ≧ 5.6, the electron flux is predicted most accurately by including also the solar wind velocity and then the dynamic pressure, respectively. The Dst index is the best overall single parameter for predicting at 3 ≦ L ≦ 6, while for the GEO flux prediction, the KP index is better than Dst. A test calculation demonstrates that the model successfully predicts the timing and location of the flux maximum as much as 2 days in advance and that the electron flux decreases faster with time at higher L values, both model features consistent with the actually observed behavior.

  17. Prediction of MeV electron fluxes throughout the outer radiation belt using multivariate autoregressive models

    SciTech Connect

    Sakaguchi, Kaori; Nagatsuma, Tsutomu; Reeves, Geoffrey D.; Spence, Harlan E.

    2015-12-22

    The Van Allen radiation belts surrounding the Earth are filled with MeV-energy electrons. This region poses ionizing radiation risks for spacecraft that operate within it, including those in geostationary orbit (GEO) and medium Earth orbit. In order to provide alerts of electron flux enhancements, 16 prediction models of the electron log-flux variation throughout the equatorial outer radiation belt as a function of the McIlwain L parameter were developed using the multivariate autoregressive model and Kalman filter. Measurements of omnidirectional 2.3 MeV electron flux from the Van Allen Probes mission as well as >2 MeV electrons from the GOES 15 spacecraft were used as the predictors. Furthermore, we selected model explanatory parameters from solar wind parameters, the electron log-flux at GEO, and geomagnetic indices. For the innermost region of the outer radiation belt, the electron flux is best predicted by using the Dst index as the sole input parameter. For the central to outermost regions, at L≥4.8 and L ≥5.6, the electron flux is predicted most accurately by including also the solar wind velocity and then the dynamic pressure, respectively. The Dst index is the best overall single parameter for predicting at 3 ≤ L ≤ 6, while for the GEO flux prediction, the KP index is better than Dst. Finally, a test calculation demonstrates that the model successfully predicts the timing and location of the flux maximum as much as 2 days in advance and that the electron flux decreases faster with time at higher L values, both model features consistent with the actually observed behavior.

  18. Characteristics of heat flux and electromagnetic electron-cyclotron instabilities driven by solar wind electrons

    NASA Astrophysics Data System (ADS)

    Saeed, Sundas; Yoon, P. H.; Sarfraz, M.; Qureshi, M. N. S.

    2017-04-01

    In situ observations reveal the existence of electron velocity distribution function in the solar wind, where the net distribution can be modelled by a combination of core, halo and strahl. These components often possess a relative drift and with respective temperature anisotropies. The relative drift between the core and halo components leads to heat flux (HF) instability, while temperature anisotropies drive electromagnetic electron-cyclotron (EMEC) instability. These instabilities have been separately studied in the literature, but for the first time, the present study combines both unstable modes in the presence of two free energy sources, namely, excessive parallel pressure and excessive perpendicular temperature. HF instability (which is a left-hand circularly polarized mode) is effectively similar to electron firehose instability, except that the free energy is provided by net relative drift among two component electrons in the background of protons. The HF instability is discussed here along with (the right-hand polarized) EMEC instability driven by temperature anisotropy. The unstable HF mode is conventionally termed the 'whistler' HF instability, but it is actually polarized in the opposite sense to the whistler wave. EMEC mode, on the other hand, reduces to the proper whistler wave in the absence of free energy source. The present combined analysis clarifies the polarization characteristics of these two modes in an unambiguous manner.

  19. Regulation of the solar wind electron heat flux from 1 to 5 AU: Ulysses observations

    SciTech Connect

    Scime, E.E.; Bame, S.J.; Feldman, W.C.; Gary, S.P.; Phillips, J.L.; Balogh, A.

    1994-12-01

    In this study the authors use observations from the three-dimensional electron spectrometer and magnetometer aboard the Ulysses spacecraft to examine the solar wind electron heat flux from 1.2 to 5.4 AU in the ecliptic plane. Throughout Ulysses` transit to 5.4 AU, the electron heat flux decreases more rapidly ({approximately}R{sup {minus}3.0}) than simple collisionless expansion along the local magnetic field and is smaller than expected for a thermal gradient heat flux, q{sub {parallel}}e(r)={minus}k{sub {parallel}}{del}{sub {parallel}}T{sub e}(r). The radial gradients and magnitudes expected for a number of electron heat flux regulatory mechanisms are examined and compared to the observations. The best agreement is found for heat flux regulation by the whistler heat flux instability. The upper bound and radial scaling for the electron heat flux predicted for the whistler heat flux instability are consistent with observations.

  20. Relativistic electron losses by microbursts and their relationship to flux decay time scales

    NASA Astrophysics Data System (ADS)

    Kanekal, S. G.; Baker, D. N.; Fennell, J. F.; Klecker, B.

    2011-12-01

    Rapid fluctuations of electron fluxes on timescales of milliseconds have long been observed and have recently drawn attention as a major process of loss of relativistic electrons from the Earth's outer radiation belts. Studies suggest that recently observed large-amplitude whistler wave packets may be closely associated with electron precipitation microbursts.We study relativistic electron losses in the outer radiation belts by characterizing decay timescales at low altitudes and investigate their relationship to microbursts. We use data collected by SAMPEX, a low-Earth orbiting spacecraft in a highly inclined polar orbit to characterize electron flux decay timescales. The LICA,HILT and PET sensors onboard SAMPEX measure electrons in various integral and differential channels. Using high resolution measurements made by the HILT sensor we identify and quantify electron microburst characteristics. We report here on our investigations of the interconnection between flux decay times and microbursts both using case studies and on a statistical basis.

  1. Fast tokamak plasma flux and electron density reconstruction technique

    SciTech Connect

    Chiang, K.L.; Hallock, G.A.; Wootton, A.J.; Wang, L.

    1997-01-01

    Density profiles in TEXT-U are obtained using a vertical viewing far-infrared (FIR) interferometer. To obtain the local (inverted) density, we have developed a simple analytic model of the plasma equilibrium configuration which is faster than EFIT (a flux surface reconstruction program) and can be easily computed between discharges. This analytic solution of the Grad{endash}Shafranov equation is valid as long as the pressure p is a function of poloidal flux {psi}, i.e., p=p({psi}). The procedure incorporates both magnetic and FIR density data to solve the Grad{endash}Shafranov equation, and provides a density profile which is self-consistent with the reconstructed equilibrium flux surfaces. Examples are presented. {copyright} {ital 1997 American Institute of Physics.}

  2. Electronic delocalization and persistent currents in nonsymmetric-dimer mesoscopic rings threaded by magnetic flux

    NASA Astrophysics Data System (ADS)

    Hu, X. F.; Peng, Z. H.; Peng, R. W.; Liu, Y. M.; Qiu, F.; Huang, X. Q.; Hu, A.; Jiang, S. S.

    2004-06-01

    We investigate electronic delocalization and magnetic-flux-induced persistent current in the mesoscopic ring, which is constructed according to the nonsymmetric-dimer (NSD) model. The flux-dependent energy spectra, electronic wavefunctions, and persistent currents are theoretically obtained. It is demonstrated that due to the localization-delocalization transition of electrons, the electronic state in the NSD ring can be localized, extended, and the intermediate case between extended states and localized ones. The persistent current (PC) approaches the behavior of free electrons if the Fermi level is around the near-resonant energy. Otherwise, the PC is depressed dramatically. This conclusion could be generalized to other correlated-disordered systems.

  3. Unfolding The High Energy Electron Flux From CRRES Fluxmeter Measurements.

    DTIC Science & Technology

    1996-12-01

    process. The algorithm used by the Fortran 90 code is Jacobi iteration. The Jacobi method iterates to solve a linear system of the form Ax = B. (2-24...The Jacobi method requires an initial estimate of the flux, <pmitial, the subroutine uses Dŕ • yM. Iterations continue until the difference between...c = MatMul(Dinv,b) x = c ! Starting guess ! This is the loop which actually computes the values of the ! unfolded fluxes by using the Jacobi method . See

  4. Neutral hydrogen flux measured at 100- to 200-km altitude in an electron aurora

    NASA Technical Reports Server (NTRS)

    Iglesias, G. E.; Anderson, H. R.

    1975-01-01

    Neutral hydrogen fluxes were measured at altitudes of 120-200 km by a rocket payload that also measured electron and proton fluxes and vector magnetic fields. An intense electron arc was crossed, while an upper limit to the flux of 0.5- to 20-keV protons was 1,000,000 per sq cm s sr keV. A neutral flux of 50,000,000 per sq cm s sr was observed, assuming hydrogen with greater than 1-keV energy, with greater north-south extent than the electron flux. Its pitch angle distribution was peaked toward 90 deg, tending toward isotropy in the center. This is fitted to a model describing spreading of an initial proton arc above 500 km.

  5. Fermi-LAT upper limits on gamma-ray emission from colliding wind binaries

    DOE PAGES

    Werner, Michael; Reimer, O.; Reimer, A.; ...

    2013-07-09

    Here, colliding wind binaries (CWBs) are thought to give rise to a plethora of physical processes including acceleration and interaction of relativistic particles. Observation of synchrotron radiation in the radio band confirms there is a relativistic electron population in CWBs. Accordingly, CWBs have been suspected sources of high-energy γ-ray emission since the COS-B era. Theoretical models exist that characterize the underlying physical processes leading to particle acceleration and quantitatively predict the non-thermal energy emission observable at Earth. Furthermore, we strive to find evidence of γ-ray emission from a sample of seven CWB systems: WR 11, WR 70, WR 125, WRmore » 137, WR 140, WR 146, and WR 147. Theoretical modelling identified these systems as the most favourable candidates for emitting γ-rays. We make a comparison with existing γ-ray flux predictions and investigate possible constraints. We used 24 months of data from the Large Area Telescope (LAT) on-board the Fermi Gamma Ray Space Telescope to perform a dedicated likelihood analysis of CWBs in the LAT energy range. As a result, we find no evidence of γ-ray emission from any of the studied CWB systems and determine corresponding flux upper limits. For some CWBs the interplay of orbital and stellar parameters renders the Fermi-LAT data not sensitive enough to constrain the parameter space of the emission models. In the cases of WR140 and WR147, the Fermi -LAT upper limits appear to rule out some model predictions entirely and constrain theoretical models over a significant parameter space. A comparison of our findings to the CWB η Car is made.« less

  6. Fermi-LAT upper limits on gamma-ray emission from colliding wind binaries

    SciTech Connect

    Werner, Michael; Reimer, O.; Reimer, A.; Egberts, K.

    2013-07-09

    Here, colliding wind binaries (CWBs) are thought to give rise to a plethora of physical processes including acceleration and interaction of relativistic particles. Observation of synchrotron radiation in the radio band confirms there is a relativistic electron population in CWBs. Accordingly, CWBs have been suspected sources of high-energy γ-ray emission since the COS-B era. Theoretical models exist that characterize the underlying physical processes leading to particle acceleration and quantitatively predict the non-thermal energy emission observable at Earth. Furthermore, we strive to find evidence of γ-ray emission from a sample of seven CWB systems: WR 11, WR 70, WR 125, WR 137, WR 140, WR 146, and WR 147. Theoretical modelling identified these systems as the most favourable candidates for emitting γ-rays. We make a comparison with existing γ-ray flux predictions and investigate possible constraints. We used 24 months of data from the Large Area Telescope (LAT) on-board the Fermi Gamma Ray Space Telescope to perform a dedicated likelihood analysis of CWBs in the LAT energy range. As a result, we find no evidence of γ-ray emission from any of the studied CWB systems and determine corresponding flux upper limits. For some CWBs the interplay of orbital and stellar parameters renders the Fermi-LAT data not sensitive enough to constrain the parameter space of the emission models. In the cases of WR140 and WR147, the Fermi -LAT upper limits appear to rule out some model predictions entirely and constrain theoretical models over a significant parameter space. A comparison of our findings to the CWB η Car is made.

  7. Simulation of high-energy radiation belt electron fluxes using NARMAX-VERB coupled codes.

    PubMed

    Pakhotin, I P; Drozdov, A Y; Shprits, Y Y; Boynton, R J; Subbotin, D A; Balikhin, M A

    2014-10-01

    This study presents a fusion of data-driven and physics-driven methodologies of energetic electron flux forecasting in the outer radiation belt. Data-driven NARMAX (Nonlinear AutoRegressive Moving Averages with eXogenous inputs) model predictions for geosynchronous orbit fluxes have been used as an outer boundary condition to drive the physics-based Versatile Electron Radiation Belt (VERB) code, to simulate energetic electron fluxes in the outer radiation belt environment. The coupled system has been tested for three extended time periods totalling several weeks of observations. The time periods involved periods of quiet, moderate, and strong geomagnetic activity and captured a range of dynamics typical of the radiation belts. The model has successfully simulated energetic electron fluxes for various magnetospheric conditions. Physical mechanisms that may be responsible for the discrepancies between the model results and observations are discussed.

  8. Simulation of high-energy radiation belt electron fluxes using NARMAX-VERB coupled codes

    PubMed Central

    Pakhotin, I P; Drozdov, A Y; Shprits, Y Y; Boynton, R J; Subbotin, D A; Balikhin, M A

    2014-01-01

    This study presents a fusion of data-driven and physics-driven methodologies of energetic electron flux forecasting in the outer radiation belt. Data-driven NARMAX (Nonlinear AutoRegressive Moving Averages with eXogenous inputs) model predictions for geosynchronous orbit fluxes have been used as an outer boundary condition to drive the physics-based Versatile Electron Radiation Belt (VERB) code, to simulate energetic electron fluxes in the outer radiation belt environment. The coupled system has been tested for three extended time periods totalling several weeks of observations. The time periods involved periods of quiet, moderate, and strong geomagnetic activity and captured a range of dynamics typical of the radiation belts. The model has successfully simulated energetic electron fluxes for various magnetospheric conditions. Physical mechanisms that may be responsible for the discrepancies between the model results and observations are discussed. PMID:26167432

  9. Energetic electron precipitation into the middle atmosphere -- Constructing the loss cone fluxes from MEPED POES

    NASA Astrophysics Data System (ADS)

    Nesse Tyssøy, H.; Sandanger, M. I.; Ødegaard, L.-K. G.; Stadsnes, J.; Aasnes, A.; Zawedde, A. E.

    2016-06-01

    The impact of energetic electron precipitation (EEP) on the chemistry of the middle atmosphere (50-90 km) is still an outstanding question as accurate quantification of EEP is lacking due to instrumental challenges and insufficient pitch angle coverage of current particle detectors. The Medium Energy Proton and Electron Detectors (MEPED) instrument on board the NOAA/Polar Orbiting Environmental Satellites (POES) and MetOp spacecraft has two sets of electron and proton telescopes pointing close to zenith (0°) and in the horizontal plane (90°). Using measurements from either the 0° or 90° telescope will underestimate or overestimate the bounce loss cone flux, respectively, as the energetic electron fluxes are often strongly anisotropic with decreasing fluxes toward the center of the loss cone. By combining the measurements from both telescopes with electron pitch angle distributions from theory of wave-particle interactions in the magnetosphere, a complete bounce loss cone flux is constructed for each of the electron energy channels >50 keV, >100 keV, and >300 keV. We apply a correction method to remove proton contamination in the electron counts. We also account for the relativistic (>1000 keV) electrons contaminating the proton detector at subauroral latitudes. This gives us full range coverage of electron energies that will be deposited in the middle atmosphere. Finally, we demonstrate the method's applicability on strongly anisotropic pitch angle distributions during a weak geomagnetic storm in February 2008. We compare the electron fluxes and subsequent energy deposition estimates to OH observations from the Microwave Limb Sounder on the Aura satellite substantiating that the estimated fluxes are representative for the true precipitating fluxes impacting the atmosphere.

  10. Electronic Reliability and the Environmental Thermal Neutron Flux

    DTIC Science & Technology

    2007-11-02

    several Californium sources of varying strengths. The room is ten by ten by three meters. It is below ground with concrete walls. In a high flux...desirable for calibrating the system. Californium -252 is a self-fissioning fast neutron source, which can be moderated to produce thermal neutrons...NIST has several Californium sources with strengths as high as 200 mrem/h at one meter. The Cf sources are stored below the floor for the safety

  11. Electron heat flux dropouts in the solar wind - Evidence for interplanetary magnetic field reconnection?

    NASA Technical Reports Server (NTRS)

    Mccomas, D. J.; Gosling, J. T.; Phillips, J. L.; Bame, S. J.; Luhmann, J. G.; Smith, E. J.

    1989-01-01

    An examination of ISEE-3 data from 1978 reveal 25 electron heat flux dropout events ranging in duration from 20 min to over 11 hours. The heat flux dropouts are found to occur in association with high plasma densities, low plasma velocities, low ion and electron temperatures, and low magnetic field magnitudes. It is suggested that the heat flux dropout intervals may indicate that the spacecraft is sampling plasma regimes which are magnetically disconnected from the sun and instead are connected to the outer heliosphere at both ends.

  12. The association of spacecraft anomalies with electron/proton particle fluxes at different orbits

    NASA Astrophysics Data System (ADS)

    Yi, K.; Moon, Y. J.

    2016-12-01

    In this study, we investigate 195 satellite anomaly data from 1998 to 2010 from Satellite News Digest (SND) to understand the association between spacecraft anomaly and space weather condition. The spacecraft anomalies are classified into Attitude & Propulsion, Power, Control, Telemetry, Instrument and unknown. For the investigation we divide these data according to the spacecraft orbit and launched year. Spacecraft's orbits are classified into the following two groups : (1) high altitude and low inclination, and (2) low altitude and high inclination. Launched year of spacecraft are divided into two groups: 1991 1998 and 1999 2007. We examine the association between these anomaly data and daily peak particle (electron and proton) flux data from GOES as well as their occurrence rates. To determine the association, we use two criteria that electron criterion is >10,000 pfu and proton criterion is >100 pfu. Main results from this study are as follows. First, the number of days satisfying the criteria for electron flux has a peak near a week before the anomaly day and decreases from the peak day to the anomaly day, while that for proton flux has a peak near the anomaly day. Second, we found a similar pattern for the mean daily peak particle (electron and proton) flux as a function of day before the anomaly day. Third, an examination of multiple spacecraft anomaly events, which are likely to occur by severe space weather effects, shows that anomalies mostly occur either when electron fluxes are in the declining stage, or when daily proton peak fluxes are strongly enhanced. Fourth, the time delay between the anomaly day and the day having the highest daily peak electron flux for the recent launching period (1999-2007) is noticeably larger than those for the older periods, implying that the anomaly characteristics associated with electron flux change with time.

  13. Simultaneous plasma wave and electron flux observations upstream of the Martian bow shock

    NASA Astrophysics Data System (ADS)

    Skalsky, A.; Grard, R.; Kiraly, P.; Klimov, S.; Kopanyi, V.; Schwingenschuh, K.; Trotignon, J. G.

    1993-03-01

    Flux enhancements of electrons with energies between 100 and 530 eV are observed simultaneously with electron plasma waves in the upstream region of the Martian bow shock. The electron flux appears to reach its maximum when the pitch angle is close to 0 deg, which corresponds to particles reflected from the shock region and backstreaming in the solar wind along the magnetic field. The correlation between high-frequency waves and enhanced electron fluxes is reminiscent of several studies on the electron foreshock of the Earth. Such a similarity indicates that, in spite of major differences between the global shock structures, the microscopic processes operating in the foreshocks of Earth and Mars are probably identical.

  14. Evaluation of the Antiproton Flux from the Antineutrino Electron Scattering

    NASA Astrophysics Data System (ADS)

    Alekseev, V. V.; Belotsky, K. M.; Bogomolov, Yu V.; Budaev, R. I.; Dunaeva, O. A.; Kirillov, A. A.; Kuznetsov, A. V.; Laletin, M. N.; Lukyanov, A. D.; Malakhov, V. V.; Mayorov, A. G.; Mayorova, M. A.; Mosichkin, A. F.; Okrugin, A. A.; Rodenko, S. A.; Shitova, A. M.

    2016-02-01

    Recent experiments in high enegry cosmic ray physics, PAMELA and AMS-02, excite a new interest to the mechanisms of generation of galactic antiparticles. In spite of the fact that global picture coincides with the predictions of the standard model, there are some black spots stimulating scientists to involve into research a particularly new physics like dark matter. In the present work, we make an attempt to estimate the impact of standard neutrino processes into the total flux of secondary antiprotons detected by contemporary experiments.

  15. A statistical approach to determining energetic outer radiation belt electron precipitation fluxes

    NASA Astrophysics Data System (ADS)

    Simon Wedlund, Mea; Clilverd, Mark A.; Rodger, Craig J.; Cresswell-Moorcock, Kathy; Cobbett, Neil; Breen, Paul; Danskin, Donald; Spanswick, Emma; Rodriguez, Juan V.

    2014-05-01

    Subionospheric radio wave data from an Antarctic-Arctic Radiation-Belt (Dynamic) Deposition VLF Atmospheric Research Konsortia (AARDDVARK) receiver located in Churchill, Canada, is analyzed to determine the characteristics of electron precipitation into the atmosphere over the range 3 < L < 7. The study advances previous work by combining signals from two U.S. transmitters from 20 July to 20 August 2010, allowing error estimates of derived electron precipitation fluxes to be calculated, including the application of time-varying electron energy spectral gradients. Electron precipitation observations from the NOAA POES satellites and a ground-based riometer provide intercomparison and context for the AARDDVARK measurements. AARDDVARK radiowave propagation data showed responses suggesting energetic electron precipitation from the outer radiation belt starting 27 July 2010 and lasting ~20 days. The uncertainty in >30 keV precipitation flux determined by the AARDDVARK technique was found to be ±10%. Peak >30 keV precipitation fluxes of AARDDVARK-derived precipitation flux during the main and recovery phase of the largest geomagnetic storm, which started on 4 August 2010, were >105 el cm-2 s-1 sr-1. The largest fluxes observed by AARDDVARK occurred on the dayside and were delayed by several days from the start of the geomagnetic disturbance. During the main phase of the disturbances, nightside fluxes were dominant. Significant differences in flux estimates between POES, AARDDVARK, and the riometer were found after the main phase of the largest disturbance, with evidence provided to suggest that >700 keV electron precipitation was occurring. Currently the presence of such relativistic electron precipitation introduces some uncertainty in the analysis of AARDDVARK data, given the assumption of a power law electron precipitation spectrum.

  16. Quasi-exospheric heat flux of solar-wind electrons

    NASA Technical Reports Server (NTRS)

    Eviatar, A.; Schultz, M.

    1975-01-01

    Density, bulk-velocity, and heat-flow moments are calculated for truncated Maxwellian distributions representing the cool and hot populations of solar-wind electrons, as realized at the base of a hypothetical exosphere. The electrostatic potential is thus calculated by requiring charge quasi-neutrality and the absence of electrical current. Plasma-kinetic coupling of the cool-electron and proton bulk velocities leads to an increase in the electrostatic potential and a decrease in the heat-flow moment.

  17. Rocket measurements of relativistic electrons: New features in fluxes, spectra and pitch angle distributions

    SciTech Connect

    Herrero, F.A.; Baker, D.N.; Goldberg, R.A. )

    1991-08-01

    The authors report new features of precipitating relativistic electron fluxes measured on a spinning sounding rocket payload at midday between altitudes of 70 and 130 km in the auroral region (Poker Flat, Alaska, 65.1{degree}N, 147.5{degree}W, and L = 5.5). The sounding rocket (NASA 33.059) was launched at 21:29 UT on May 13, 1990 during a relativistic electron enhancement event of modest intensity. Electron fluxes were measured for a total of about 210 seconds at energies from 0.1 to 3.8 MeV, while pitch angle was sampled from 0{degree} to 90{degree} every spin cycle. Flux levels during the initial 90 seconds were about 5 to 8 times higher than in the next 120 seconds, revealing a time scale of more than 100 seconds for large amplitude intensity variations. A shorter time scale appeared for downward electron bursts lasting 10 to 20 seconds. Electrons with energies below about 0.2 MeV showed isotropic pitch angle distributions during most of the first 90 seconds of data, while at higher energies the electrons had highest fluxes near the mirroring angle (90{degree}); when they occurred, the noted downward bursts were seen at all energies. Data obtained during the second half of the flight showed little variation in the shape of the pitch angle distribution for energies greater than 0.5 MeV; the flux at 90{degree} was about 100 times the flux at 0{degree}. They have compared the low altitude fluxes with those measured at geostationary orbit (L = 6.6), and find that the low altitude fluxes are much higher than expected from a simple mapping of a pancake distribution at high altitudes (at the equator). Energy deposition of this modest event is estimated to increase rapidly above 45 km, already exceeding the cosmic ray background at 45 km.

  18. The seasonal dependence of relativistic electron fluxes in the Earth's outer van Allen Belt

    NASA Astrophysics Data System (ADS)

    Kanekal, S. G.; Baker, D. N.; McPherron, R.

    2007-12-01

    It is well known that geomagnetic activity shows a marked seasonal dependence. This effect has been attributed to the seasonal variation of the Earth's dipole tilt angle exposing the magnetosphere to an increased southward component of the interplanetary field (the Russell-McPherron effect) or an increased solar wind velocity (the axial/equinoctial effect). We examine the seasonal dependence of relativistic electron fluxes in the Earth's outer Van Allen belt. An earlier investigation by Baker et. al., (1999) found that the relativistic electron fluxes do show a strong seasonal dependence with the equinoctial electron fluxes being almost three times higher than the solstitial fluxes. We extend this previous investigation using data obtained by sensors onboard SAMPEX. This study of the seasonal dependence is based on data with a higher time resolution as compared to the earlier study. The results of our analysis show that the peak electron fluxes are shifted in time from the nominal equinoctial times. We discuss some possible implications of our observations in the context of electron energization in the Earth's magnetosphere. Baker, D.N., S.G. Kanekal, T.I. Pulkkinen, and J.B. Blake, Equinoctial and solstitial averages of magnetospheric relativistic electrons: A strong semiannual modulation, Geophys. Res. Lett., 26, No. 20, 3193-3196, 1999.

  19. Predictions of vehicle encountered electron and proton fluxes for the UK-4 spacecraft

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.

    1972-01-01

    Updated radiation data were obtained for the UK-4 satellite by performing orbital flux integrations for protons and electrons along a specified flight path, using current field and environment models. In this process, adjustments were made to the electron data to account for temporal variations. The final results are presented in tabular and graphical form.

  20. Rapid increase in relativistic electron flux controlled by nonlinear phase trapping of whistler chorus elements

    NASA Astrophysics Data System (ADS)

    Saito, Shinji; Miyoshi, Yoshizumi; Seki, Kanako

    2016-07-01

    Wave-particle interactions with whistler chorus waves are believed to provide a primary acceleration for electrons in the outer radiation belt. Previous models for flux enhancement of the radiation belt have assumed the stochastic process as a diffusion manner of successive random-phase interactions, but physical mechanisms for the acceleration are not fully incorporated in these models because of the lack of a nonlinear scattering process. Here we report rapid increase in relativistic electron flux by using an innovative computer simulation model that incorporates not only diffusive process but also nonlinear scattering processes. The simulations show that three types of scattering simultaneously occur, which are diffusive, phase trapping, and phase bunching. It is found that the phase trapping is the most efficient mechanism to produce the MeV electrons rapidly in the scattering processes. The electrons are accelerated from 400 keV to over 1 MeV in time scale less than 60 s. On the other hand, as the phase trapping is suppressed by the breaking of relative phase angle between waves and gyrating electrons during the interaction, the increase of electron flux at MeV energy is clearly reduced. Our simulations conclude that the phase-trapping process causes a significant effect for the increase in relativistic electron flux and suggest that a quasi-linear diffusion model is not always valid to fully describe the relativistic electron acceleration.

  1. High flux, narrow bandwidth compton light sources via extended laser-electron interactions

    DOEpatents

    Barty, V P

    2015-01-13

    New configurations of lasers and electron beams efficiently and robustly produce high flux beams of bright, tunable, polarized quasi-monoenergetic x-rays and gamma-rays via laser-Compton scattering. Specifically, the use of long-duration, pulsed lasers and closely-spaced, low-charge and low emittance bunches of electron beams increase the spectral flux of the Compton-scattered x-rays and gamma rays, increase efficiency of the laser-electron interaction and significantly reduce the overall complexity of Compton based light sources.

  2. Diagnosing pure-electron plasmas with internal particle flux probes.

    PubMed

    Kremer, J P; Pedersen, T Sunn; Marksteiner, Q; Lefrancois, R G; Hahn, M

    2007-01-01

    Techniques for measuring local plasma potential, density, and temperature of pure-electron plasmas using emissive and Langmuir probes are described. The plasma potential is measured as the least negative potential at which a hot tungsten filament emits electrons. Temperature is measured, as is commonly done in quasineutral plasmas, through the interpretation of a Langmuir probe current-voltage characteristic. Due to the lack of ion-saturation current, the density must also be measured through the interpretation of this characteristic thereby greatly complicating the measurement. Measurements are further complicated by low densities, low cross field transport rates, and large flows typical of pure-electron plasmas. This article describes the use of these techniques on pure-electron plasmas in the Columbia Non-neutral Torus (CNT) stellarator. Measured values for present baseline experimental parameters in CNT are phi(p)=-200+/-2 V, T(e)=4+/-1 eV, and n(e) on the order of 10(12) m(-3) in the interior.

  3. Analysis of Voyager Observed High-Energy Electron Fluxes in the Heliosheath Using MHD Simulations

    NASA Technical Reports Server (NTRS)

    Washimi, Haruichi; Webber, W. R.; Zank, Gary P.; Hu, Qiang; Florinski, Vladimir; Adams, James; Kubo, Yuki

    2011-01-01

    The Voyager spacecraft (V1 and V2) observed electrons of 6-14 MeV in the heliosheath which showed several incidences of flux variation relative to a background of gradually increasing flux with distance from the Sun. The increasing flux of background electrons is thought to result from inward radial diffusion. We compare the temporal electron flux variation with dynamical phenomena in the heliosheath that are obtained from our MHD simulations. Because our simulation is based on V2 observed plasma data before V2 crossed the termination shock, this analysis is effective up to late 2008, i.e., about a year after the V2-crossing, during which disturbances, driven prior to the crossing time, survived in the heliosheath. Several electron flux variations correspond to times directly associated with interplanetary shock events. One noteworthy example corresponds to various times associated with the March 2006 interplanetary shock, these being the collision with the termination shock, the passage past the V1 spacecraft, and the collision with the region near the heliopause, as identified by W.R. Webber et al. for proton/helium of 7-200 MeV. Our simulations indicate that all other electron flux variations, except one, correspond well to the times when a shock-driven magneto-sonic pulse and its reflection in the heliosheath either passed across V1/V2, or collided with the termination shock or with the plasma sheet near the heliopause. This result suggests that variation in the electron flux should be due to either direct or indirect effects of magnetosonic pulses in the heliosheath driven by interplanetary shocks

  4. The Electronic Flux in Chemical Reactions. Insights on the Mechanism of the Maillard Reaction

    NASA Astrophysics Data System (ADS)

    Flores, Patricio; Gutiérrez-Oliva, Soledad; Herrera, Bárbara; Silva, Eduardo; Toro-Labbé, Alejandro

    2007-11-01

    The electronic transfer that occurs during a chemical process is analysed in term of a new concept, the electronic flux, that allows characterizing the regions along the reaction coordinate where electron transfer is actually taking place. The electron flux is quantified through the variation of the electronic chemical potential with respect to the reaction coordinate and is used, together with the reaction force, to shed light on reaction mechanism of the Schiff base formation in the Maillard reaction. By partitioning the reaction coordinate in regions in which different process might be taking place, electronic reordering associated to polarization and transfer has been identified and found to be localized at specific transition state regions where most bond forming and breaking occur.

  5. Correlation between Poynting flux and soft electron precipitation in the dayside polar cap boundary regions.

    PubMed

    Deng, Yue; Sheng, Cheng; Su, Yi-Jiun; Hairston, Marc R; Knipp, Delores; Huang, Cheryl Y; Ober, Daniel; Redmon, Rob J; Coley, Robin

    2015-10-01

    Observations have revealed large Poynting flux and soft electron precipitation around the cusp region, which have strong impacts on the polar ionosphere/thermosphere. Simulations also confirmed that Poynting flux and soft electron precipitation significantly change the neutral density and dynamics around the dayside polar cap boundary regions. However, no detailed study has been conducted to show if they should coincide with each other or not. Our analysis of Defense Meteorological Satellite Program (DMSP) satellite data reveals a complex correlation between them. Poynting flux and soft particle precipitation are coincident in some cases (match cases), but a clear displacement between them can also be identified in others (nonmatch cases). In the 29 cusp crossings from F13 we investigated, the ratio between nonmatch and match cases is close to 1:4. In nonmatch cases, the displacement between the Poynting flux enhancement and soft particle precipitation enhancement can be as large as 1° in geomagnetic latitude.

  6. Vortices and Flux Ropes in Electron MHD Plasmas I

    NASA Astrophysics Data System (ADS)

    Stenzel, R. L.; Urrutia, J. M.; Griskey, M. C.

    Laboratory experiments are reviewed which demonstrate the existence and properties of three-dimensional vortices in Electron MHD (EMHD) plasmas. In this parameter regime the electrons form a magnetized fluid which is charge-neutralized by unmagnetized ions. The observed vortices are time-varying flows in the electron fluid which produce currents and magnetic fields, the latter superimposed on a uniform dc magnetic field B0. The topology of the time-varying flows and fields can be described by linked toroidal and poloidal vector fields with amplitude distributions ranging from spherical to cylindrical shape. Vortices can be excited with pulsed currents to electrodes, pulsed currents in magnetic loop antennas, and heat pulses. The vortices propagate in the whistler mode along the mean field B0. In the presence of dissipation, magnetic self-helicity and energy decay at the same rate. Reversal of B or propagation direction changes the sign of the helicity. Helicity injection produces directional emission of vortices. Reflection of a vortex violates helicity conservation and field-line tying. Part I of two companion papers reviews the linear vortex properties while the companion Part II describes nonlinear EMHD phenomena and instabilities.

  7. Gas dynamic theory of flight of fast electron flux in plasma

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.

    The one-dimensional flight of a fast electron flux in plasma is investigated taking into account generation and absorption of plasma waves. The transition from the kinetic description to the gas dynamics is made. The closed set of gas dynamic equations for electrons and plasmons is derived and an automodel solution is obtained in the case of instantaneous injection. This solution represents the beam-plasma formation on natural oscillations in the system electrons+plasmons is considered.

  8. Magnetic-flux quanta in superconducting thin films observed by electron holography and digital phase analysis

    SciTech Connect

    Hasegawa, S.; Matsuda, T.; Endo, J.; Osakabe, N.; Igarashi, M.; Kobayashi, T.; Naito, M.; Tonomura, A. ); Aoki, R. )

    1991-04-01

    Singly quantized magnetic fluxes in superconducting lead films have been directly observed in the form of magnetic-flux-line distributions by using an electron-holography technique. Combining this with the digital-phase-analysis method, we were able to determine the flux quantum {ital h}/2{ital e} for individual fluxes with a precision of {similar to}{ital h}/100{ital e}, and analyze the distributions of field-vector components around the fluxon centers. The internal-field distributions obtained were compared with those calculated from the Ginzburg-Landau equations with use of some models, and an overall agreement was found between them. We also observed the changes of the magnetic-flux structures of lead thin films as a function of their thickness. Fluxon pairs were observed in 0.2-{mu}m-thick films, which may correspond to those suggested by Kosterlitz-Thouless theory.

  9. The sum of flux control coefficients in the electron-transport chain of mitochondria.

    PubMed

    Brand, M D; Vallis, B P; Kesseler, A

    1994-12-15

    The sum of the flux control coefficients for group-transfer reactions such as electron transport has been proposed to be two when the coefficients are calculated from experiments in which the concentrations of the electron carriers are changed (CE) but one when they are calculated from changes in the rates of the electron-transfer processes (Cv). We tested this proposal using electron transport in uncoupled beef heart, potato tuber and rat liver mitochondria. First, with ascorbate plus N,N,N',N"-tetramethyl-p-phenylenediamine as substrate, the CE flux control coefficients of ascorbate, N,N,N',N"-tetramethyl-p-phenylenediamine, mitochondria and oxygen over electron-transport rate were measured by direct titration of the concentrations of these electron carriers. CE values were close to zero, one, one and zero, respectively, giving a sum of CE flux control coefficients of approximately two. At higher concentrations of N,N,N',N'-tetramethyl-p-phenylenediamine, its CE control decreased and the sum decreased towards one as predicted. Secondly, the Cv control coefficients of groups of electron-transfer processes with succinate or ascorbate plus N,N,N',N'-tetramethyl-p-phenylenediamine as substrate were measured. This was achieved by measuring the effects of KCN (or malonate or N,N,N',N'-tetramethyl-p-phenylenediamine) on system flux when intermediates were allowed to relax and on local flux when intermediates were held constant. The Cv flux control coefficients were calculated as the ratio of the effects on system flux and on local flux. The sum of the Cv flux control coefficients was approximately one. Whether a sum of one or a sum of two was obtained depended entirely on the definition of control coefficients that was used, since either sum was obtained from the same set of data depending on the method of calculation. Both definitions are valid, but they give different information. It is important to be aware of which definition is being used when analysing control

  10. Low-energy electron flux and its reaction to active experimentation of Spacelab

    NASA Technical Reports Server (NTRS)

    Wilhelm, K.

    1981-01-01

    An instrument capable of observing the natural electron flux in the energy range from 0.1 to 12.0 kiloelectron volts is discussed for use in an experiment intended as a forerunner of a method that will utilize artificially accelerated electrons as tracer particles for electron fields parallel to the magnetic field. Effects that are of importance either as means of detecting the echo beam or as causes of beam perturbations (e.g., spacecraft charging effects and electron background) are to be studied. The use of electron accelerators as a tool to probe magnetospheric processes rather than to modify them is planned.

  11. An empirical model of electron and ion fluxes derived from observations at geosynchronous orbit

    SciTech Connect

    Denton, M. H.; Thomsen, M. F.; Jordanova, V. K.; Henderson, M. G.; Borovsky, J. E.; Denton, J. S.; Pitchford, D.; Hartley, D. P.

    2015-04-01

    Knowledge of the plasma fluxes at geosynchronous orbit is important to both scientific and operational investigations. We present a new empirical model of the ion flux and the electron flux at geosynchronous orbit (GEO) in the energy range ~1 eV to ~40 keV. The model is based on a total of 82 satellite-years of observations from the Magnetospheric Plasma Analyzer instruments on Los Alamos National Laboratory satellites at GEO. These data are assigned to a fixed grid of 24 local-times and 40 energies, at all possible values of Kp. Bi-linear interpolation is used between grid points to provide the ion flux and the electron flux values at any energy and local-time, and for given values of geomagnetic activity (proxied by the 3-hour Kp index), and also for given values of solar activity (proxied by the daily F10.7 index). Initial comparison of the electron flux from the model with data from a Compact Environmental Anomaly Sensor II (CEASE-II), also located at geosynchronous orbit, indicate a good match during both quiet and disturbed periods. The model is available for distribution as a FORTRAN code that can be modified to suit user-requirements.

  12. An empirical model of electron and ion fluxes derived from observations at geosynchronous orbit

    DOE PAGES

    Denton, M. H.; Thomsen, M. F.; Jordanova, V. K.; ...

    2015-04-01

    Knowledge of the plasma fluxes at geosynchronous orbit is important to both scientific and operational investigations. We present a new empirical model of the ion flux and the electron flux at geosynchronous orbit (GEO) in the energy range ~1 eV to ~40 keV. The model is based on a total of 82 satellite-years of observations from the Magnetospheric Plasma Analyzer instruments on Los Alamos National Laboratory satellites at GEO. These data are assigned to a fixed grid of 24 local-times and 40 energies, at all possible values of Kp. Bi-linear interpolation is used between grid points to provide the ionmore » flux and the electron flux values at any energy and local-time, and for given values of geomagnetic activity (proxied by the 3-hour Kp index), and also for given values of solar activity (proxied by the daily F10.7 index). Initial comparison of the electron flux from the model with data from a Compact Environmental Anomaly Sensor II (CEASE-II), also located at geosynchronous orbit, indicate a good match during both quiet and disturbed periods. The model is available for distribution as a FORTRAN code that can be modified to suit user-requirements.« less

  13. Properties of electron flux spectra around the plasmapause in the chorus and hiss regions using POES.

    NASA Astrophysics Data System (ADS)

    Whittaker, Ian; Rodger, Craig; Clilverd, Mark

    2014-05-01

    The European FP7 PLASMON project aims to provide observations of plasmaspheric densities, and link the plasmaspheric variations to relativistic electron precipitation from the radiation belts. This is intended to assist in the estimation and prevent damage of space assets from space weather events as well as to improve forecasting (http://plasmon.elte.hu). As part of the PLASMON project, electron fluxes from the POES series of satellites are being used to determine the link between energetic electron precipitation energy spectra and magnitude to the position of the plasmapause. The MEPED instrument onboard POES measures electron flux from 90° (trapped particles) and 0° (losscone) telescopes, in 3 integral energy channels (>30, >100 and >300 keV). These fluxes have been compared to the DEMETER/IDP instrument to confirm that published geometric factor corrections (Yando et al. 2011) can be accurately applied to the POES data to produce as accurate as possible fluxes. These global fluxes have then been separated into regions in which Chorus (23:00-11:00 MLT) and Hiss (11:00-16:00 MLT) whistler mode waves are expected to occur, in 0.2 L-shell bins with a 20 minute temporal resolution. The plasmapause locations have been determined from the O'Brien and Moldwin (2003) models based on Kp, Ae and Dst peaks. We are currently comparing the POES spectral gradient and flux magnitude with plasmapause location and geomagnetic activity for the locations in which chorus and hiss are known to occur. This presentation will focus on the electron flux spectral gradient behaviour either side of the plasmapause, a value that is difficult to measure from ground based techniques.

  14. Correcting the NOAA/MEPED energetic electron fluxes for detector efficiency and proton contamination

    NASA Astrophysics Data System (ADS)

    Asikainen, T.; Mursula, K.

    2013-10-01

    The Medium Energy Proton and Electron Detector (MEPED) instruments onboard the NOAA/POES satellites have provided a valuable long-term database of low-altitude energetic particle observations spanning from 1978 to present. Here we study the instrumental problems of the NOAA/MEPED electron detectors and present methods to correct them. It is well known that the MEPED electron detectors are contaminated by protons of certain energy range. Using the recently corrected MEPED proton fluxes, we are now able to reliably remove this contamination. Using a simple simulation model to estimate the response of the MEPED electron detectors to incoming electrons and protons, we show that efficiencies of (Space Environment Monitors) SEM-1 and SEM-2 versions of the detectors have large differences due to different detector designs. This leads to a systematic difference between the SEM-1 and SEM-2 measurements and causes a significant long-term inhomogeneity in measured MEPED electron fluxes. Using the estimated efficiencies, we remove the proton contamination and correct the electron measurements for nonideal detector efficiency. We discuss the entire 34 year time series of MEPED measurements and show that, on an average, the correction affects different energy channels and SEM-1 and SEM-2 instruments differently. Accordingly, the uncorrected electron fluxes and electron spectra are severely distorted by nonideal detector efficiency and proton contamination, and their long-term evolution is misrepresented without the correction. The present correction of the MEPED electron fluxes over the whole interval of NOAA/POES measurements covering several solar cycles is important for long-term studies of, e.g., magnetospheric dynamics, solar activity, ionospheric research, and atmospheric effects of energetic electrons.

  15. Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

    NASA Astrophysics Data System (ADS)

    Aguilar, M.; Aisa, D.; Alvino, A.; Ambrosi, G.; Andeen, K.; Arruda, L.; Attig, N.; Azzarello, P.; Bachlechner, A.; Barao, F.; Barrau, A.; Barrin, L.; Bartoloni, A.; Basara, L.; Battarbee, M.; Battiston, R.; Bazo, J.; Becker, U.; Behlmann, M.; Beischer, B.; Berdugo, J.; Bertucci, B.; Bigongiari, G.; Bindi, V.; Bizzaglia, S.; Bizzarri, M.; Boella, G.; de Boer, W.; Bollweg, K.; Bonnivard, V.; Borgia, B.; Borsini, S.; Boschini, M. J.; Bourquin, M.; Burger, J.; Cadoux, F.; Cai, X. D.; Capell, M.; Caroff, S.; Casaus, J.; Cascioli, V.; Castellini, G.; Cernuda, I.; Cervelli, F.; Chae, M. J.; Chang, Y. H.; Chen, A. I.; Chen, H.; Cheng, G. M.; Chen, H. S.; Cheng, L.; Chikanian, A.; Chou, H. Y.; Choumilov, E.; Choutko, V.; Chung, C. H.; Clark, C.; Clavero, R.; Coignet, G.; Consolandi, C.; Contin, A.; Corti, C.; Coste, B.; Cui, Z.; Dai, M.; Delgado, C.; Della Torre, S.; Demirköz, M. B.; Derome, L.; Di Falco, S.; Di Masso, L.; Dimiccoli, F.; Díaz, C.; von Doetinchem, P.; Du, W. J.; Duranti, M.; D'Urso, D.; Eline, A.; Eppling, F. J.; Eronen, T.; Fan, Y. Y.; Farnesini, L.; Feng, J.; Fiandrini, E.; Fiasson, A.; Finch, E.; Fisher, P.; Galaktionov, Y.; Gallucci, G.; García, B.; García-López, R.; Gast, H.; Gebauer, I.; Gervasi, M.; Ghelfi, A.; Gillard, W.; Giovacchini, F.; Goglov, P.; Gong, J.; Goy, C.; Grabski, V.; Grandi, D.; Graziani, M.; Guandalini, C.; Guerri, I.; Guo, K. H.; Habiby, M.; Haino, S.; Han, K. C.; He, Z. H.; Heil, M.; Hoffman, J.; Hsieh, T. H.; Huang, Z. C.; Huh, C.; Incagli, M.; Ionica, M.; Jang, W. Y.; Jinchi, H.; Kanishev, K.; Kim, G. N.; Kim, K. S.; Kirn, Th.; Kossakowski, R.; Kounina, O.; Kounine, A.; Koutsenko, V.; Krafczyk, M. S.; Kunz, S.; La Vacca, G.; Laudi, E.; Laurenti, G.; Lazzizzera, I.; Lebedev, A.; Lee, H. T.; Lee, S. C.; Leluc, C.; Li, H. L.; Li, J. Q.; Li, Q.; Li, Q.; Li, T. X.; Li, W.; Li, Y.; Li, Z. H.; Li, Z. Y.; Lim, S.; Lin, C. H.; Lipari, P.; Lippert, T.; Liu, D.; Liu, H.; Lomtadze, T.; Lu, M. J.; Lu, Y. S.; Luebelsmeyer, K.; Luo, F.; Luo, J. Z.; Lv, S. S.; Majka, R.; Malinin, A.; Mañá, C.; Marín, J.; Martin, T.; Martínez, G.; Masi, N.; Maurin, D.; Menchaca-Rocha, A.; Meng, Q.; Mo, D. C.; Morescalchi, L.; Mott, P.; Müller, M.; Ni, J. Q.; Nikonov, N.; Nozzoli, F.; Nunes, P.; Obermeier, A.; Oliva, A.; Orcinha, M.; Palmonari, F.; Palomares, C.; Paniccia, M.; Papi, A.; Pedreschi, E.; Pensotti, S.; Pereira, R.; Pilo, F.; Piluso, A.; Pizzolotto, C.; Plyaskin, V.; Pohl, M.; Poireau, V.; Postaci, E.; Putze, A.; Quadrani, L.; Qi, X. M.; Rancoita, P. G.; Rapin, D.; Ricol, J. S.; Rodríguez, I.; Rosier-Lees, S.; Rozhkov, A.; Rozza, D.; Sagdeev, R.; Sandweiss, J.; Saouter, P.; Sbarra, C.; Schael, S.; Schmidt, S. M.; Schuckardt, D.; von Dratzig, A. Schulz; Schwering, G.; Scolieri, G.; Seo, E. S.; Shan, B. S.; Shan, Y. H.; Shi, J. Y.; Shi, X. Y.; Shi, Y. M.; Siedenburg, T.; Son, D.; Spada, F.; Spinella, F.; Sun, W.; Sun, W. H.; Tacconi, M.; Tang, C. P.; Tang, X. W.; Tang, Z. C.; Tao, L.; Tescaro, D.; Ting, Samuel C. C.; Ting, S. M.; Tomassetti, N.; Torsti, J.; Türkoǧlu, C.; Urban, T.; Vagelli, V.; Valente, E.; Vannini, C.; Valtonen, E.; Vaurynovich, S.; Vecchi, M.; Velasco, M.; Vialle, J. P.; Wang, L. Q.; Wang, Q. L.; Wang, R. S.; Wang, X.; Wang, Z. X.; Weng, Z. L.; Whitman, K.; Wienkenhöver, J.; Wu, H.; Xia, X.; Xie, M.; Xie, S.; Xiong, R. Q.; Xin, G. M.; Xu, N. S.; Xu, W.; Yan, Q.; Yang, J.; Yang, M.; Ye, Q. H.; Yi, H.; Yu, Y. J.; Yu, Z. Q.; Zeissler, S.; Zhang, J. H.; Zhang, M. T.; Zhang, X. B.; Zhang, Z.; Zheng, Z. M.; Zhuang, H. L.; Zhukov, V.; Zichichi, A.; Zimmermann, N.; Zuccon, P.; Zurbach, C.; AMS Collaboration

    2014-09-01

    Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ˜30 GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

  16. Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station.

    PubMed

    Aguilar, M; Aisa, D; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Du, W J; Duranti, M; D'Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pedreschi, E; Pensotti, S; Pereira, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

    2014-09-19

    Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30  GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

  17. Geodesic mode instability driven by electron and ion fluxes in tokamaks

    SciTech Connect

    Elfimov, A. G. Camilo de Souza, F.; Galvão, R. M. O.

    2015-11-15

    The effect of the parallel electron current and plasma flux on Geodesic Acoustic Modes (GAM) in a tokamak is analyzed by kinetic theory taking into the account the ion Landau damping and diamagnetic drifts. It is shown that the electron current and plasma flow, modeled by shifted Maxwell distributions of electrons and ions, may overcome the ion Landau damping generating the GAM instability when the parallel electron current velocity is larger than the effective parallel GAM phase velocity of sidebands, Rqω. The instability is driven by the electron current and the parallel ion flux cross term. Possible applications to tokamak experiments are discussed. The existence of the geodesic ion sound mode due to plasma flow is shown.

  18. Whistler Mode Waves and the Electron Heat Flux in the Solar Wind: Cluster Observations

    NASA Astrophysics Data System (ADS)

    Lacombe, C.; Alexandrova, O.; Matteini, L.; Santolík, O.; Cornilleau-Wehrlin, N.; Mangeney, A.; de Conchy, Y.; Maksimovic, M.

    2014-11-01

    The nature of the magnetic field fluctuations in the solar wind between the ion and electron scales is still under debate. Using the Cluster/STAFF instrument, we make a survey of the power spectral density and of the polarization of these fluctuations at frequencies f in [1, 400] Hz, during five years (2001-2005), when Cluster was in the free solar wind. In ~10% of the selected data, we observe narrowband, right-handed, circularly polarized fluctuations, with wave vectors quasi-parallel to the mean magnetic field, superimposed on the spectrum of the permanent background turbulence. We interpret these coherent fluctuations as whistler mode waves. The lifetime of these waves varies between a few seconds and several hours. Here, we present, for the first time, an analysis of long-lived whistler waves, i.e., lasting more than five minutes. We find several necessary (but not sufficient) conditions for the observation of whistler waves, mainly a low level of background turbulence, a slow wind, a relatively large electron heat flux, and a low electron collision frequency. When the electron parallel beta factor β e∥ is larger than 3, the whistler waves are seen along the heat flux threshold of the whistler heat flux instability. The presence of such whistler waves confirms that the whistler heat flux instability contributes to the regulation of the solar wind heat flux, at least for β e∥ >= 3, in slow wind at 1 AU.

  19. Increases of relativistic and subrelativistic electron fluxes and position of auroral oval.

    NASA Astrophysics Data System (ADS)

    Riazantseva, Maria; Myagkova, Irina; Antonova, Elizaveta; Denisov, Yuriy I.; Marjin, Boris; Karavaev, Michael; Saveliev, Michael; Feigin, Viktor

    Increases of fluxes of relativistic and subrelativistic electrons and simultaneous plasma ob-servations are studied using data of low orbiting METEOR-3M (operating from 2001 till 2005), METEOR-M 1 (launched September 2009), CORONAS-F (2002-2005) and CORONAS-PHOTON (launched January 2009) satellites. Results of measurements are compared with simultaneous solar wind observations. The variations of particle fluxes at the external bound-ary of the outer electron radiation belt are analyzed and compared with plasma observations. The events of the appearance of local increases of energetic electron fluxes are selected. Some of these increases have near the same profile and values during 2-3 consecutive orbits. Comparison of analyzed increases and fluxes of plasma particles with energies till 10 keV show that prac-tically for all events when such comparison was possible increases of fluxes of relativistic and subrelativistic electrons were observed inside the auroral oval. The nature of observed events is discussed. It is shown that the hypothesis of the appearance of local traps for energetic particles can help to explain the observed phenomena.

  20. Role of LAT in the Granule-Mediated Cytotoxicity of CD8 T Cells

    PubMed Central

    Ou-Yang, Chih-wen; Zhu, Minghua; Fuller, Deirdre M.; Sullivan, Sarah A.; Chuck, Mariana I.; Ogden, Sarah

    2012-01-01

    Linker for activation of T cells (LAT) is a transmembrane adaptor protein that is essential to bridge T cell receptor (TCR) engagement to downstream signaling events. The indispensable role of LAT in thymocyte development and T cell activation has been well characterized; however, the function of LAT in cytotoxic-T-lymphocyte (CTL) cytotoxicity remains unknown. We show here that LAT-deficient CTLs failed to upregulate FasL and produce gamma interferon after engagement with target cells and had impaired granule-mediated killing. We further dissected the effect of the LAT deletion on each step of granule exocytosis. LAT deficiency led to altered synapse formation, subsequently causing unstable T cell–antigen-presenting cell (APC) conjugates. Microtubule organizing center polarization and granule reorientation were also impaired by LAT deficiency, leading to reduced granule delivery. Despite these defects, granule release was still observed in LAT-deficient CTLs due to residual calcium flux and phospholipase C (PLC) activity. Our data demonstrated that LAT-mediated signaling intricately regulates CTL cytotoxicity at multiple steps. PMID:22566687

  1. High-flux electron beams from laser wakefield accelerators driven by petawatt lasers

    NASA Astrophysics Data System (ADS)

    Zeng, Ming; Tesileanu, Ovidiu

    2017-07-01

    Laser wakefield accelerators (LWFAs) are considered to be one of the most competitive next-generation accelerator candidates. In this paper, we will study the potential high-flux electron beam production of an LWFA driven by petawatt-level laser pulses. In our three-dimensional particle-in-cell simulations, an optimal set of parameters gives ˜ 40 {nC} of charge with 2 {PW} laser power, thus ˜ 400 {kA} of instantaneous current if we assume the electron beam duration is 100 fs. This high flux and its secondary radiation are widely applicable in nuclear and QED physics, industrial imaging, medical and biological studies.

  2. High-flux electron beams from laser wakefield accelerators driven by petawatt lasers

    NASA Astrophysics Data System (ADS)

    Ming, ZENG; Ovidiu, TESILEANU

    2017-07-01

    Laser wakefield accelerators (LWFAs) are considered to be one of the most competitive next-generation accelerator candidates. In this paper, we will study the potential high-flux electron beam production of an LWFA driven by petawatt-level laser pulses. In our three-dimensional particle-in-cell simulations, an optimal set of parameters gives ∼ 40 {nC} of charge with 2 {PW} laser power, thus ∼ 400 {kA} of instantaneous current if we assume the electron beam duration is 100 fs. This high flux and its secondary radiation are widely applicable in nuclear and QED physics, industrial imaging, medical and biological studies.

  3. Neutrino-Electron Scattering in MINERvA for Constraining the NuMI Neutrino Flux

    SciTech Connect

    Park, Jaewon

    2013-01-01

    Neutrino-electron elastic scattering is used as a reference process to constrain the neutrino flux at the Main Injector (NuMI) beam observed by the MINERvA experiment. Prediction of the neutrino flux at accelerator experiments from other methods has a large uncertainty, and this uncertainty degrades measurements of neutrino oscillations and neutrino cross-sections. Neutrino-electron elastic scattering is a rare process, but its cross-section is precisely known. With a sample corresponding to $3.5\\times10^{20}$ protons on target in the NuMI low-energy neutrino beam, a sample of $120$ $\

  4. A new approach to predict and estimate enhancements of "killer" electron flux at geosynchronous orbit

    NASA Astrophysics Data System (ADS)

    Potapov, Alexander; Ryzhakova, Larisa; Tsegmed, Battuulai

    2016-09-01

    So-called "killer" electrons are electrons of relativistic energies (more than 1-2 MeV) forming the outer radiation belt. Their fluxes present a serious threat for on-board electronics of spacecraft orbiting in geosynchronous orbit. This provides actuality of the problem of electron flux forecast. The population of energetic electrons grows after immersion of the Earth's magnetosphere into a high-speed stream of the solar wind. One of the main mechanisms of acceleration of magnetospheric electrons to relativistic energies assumed to be their wave-particle interaction with the ultra-low-frequency or very-low-frequency waves. Accordingly, the previously proposed prognostic methods were based on the connection of the outer radiation belt population with the speed of the solar wind and the activity of the low-frequency waves in the magnetosphere. In this paper, we propose to build a forecast based on a new kind of the multiple regressions model with sliding window of predictors. A set of predictors used in the successful multiple regressions model include parameters that reflect processes of replenishment of the outer radiation belt due to the acceleration of seed electrons as well as processes of the devastation of the electron flux in the geosynchronous region due to outward adiabatic transport and outward radial diffusion. To characterize these processes, we use the following set of parameters measured on the ground and in situ: the solar wind speed, density and dynamic pressure of the interplanetary plasma, the intensity of ultra-low-frequency oscillations in front of the magnetosphere and on the ground, the flux of seed electrons (of hundreds eV energy) at geosynchronous orbit, the actual values of the magnetic field at L=6.6, and interplanetary electric field. Coefficients in the model equation are derived from experimental data using the least-squares method. Test calculations using the proposed model have shown promising results.

  5. Upper limit of electron fluxes generated by kinetic Alfvén waves in Maxwellian plasma

    NASA Astrophysics Data System (ADS)

    Artemyev, A. V.; Rankin, R.; Vasko, I. Y.

    2016-09-01

    We consider electron acceleration by kinetic Alfvén waves in the equatorial inner magnetosphere and plasma sheet boundary layer. The competition between the accelerating effect of the wave parallel electric field and mirror force acting on particles in an inhomogeneous background magnetic field generates an effective potential well where electrons can be trapped and accelerated. We compare energy variations of trapped and transient resonant electrons and show that these variations almost compensate each other. Thus, energy provided to waves by transient particles is transferred to trapped particles. This effect allows waves accelerate trapped electrons without being significantly damped. Using energy balance equations, we estimate the maximum flux of electrons accelerated via trapping into Landau resonance with kinetic Alfvén waves. For a wide range of system parameters (i.e., ion to electron temperature ratio, magnetic field amplitude, and wave number and wave frequency), acceleration of trapped electrons can generate fluxes with amplitude about 5-25% of the background thermal fluxes. We determine parametric regions for the most efficient acceleration.

  6. Extensive electron transport and energization via multiple, localized dipolarizing flux bundles

    NASA Astrophysics Data System (ADS)

    Gabrielse, Christine; Angelopoulos, Vassilis; Harris, Camilla; Artemyev, Anton; Kepko, Larry; Runov, Andrei

    2017-05-01

    Using an analytical model of multiple dipolarizing flux bundles (DFBs) embedded in earthward traveling bursty bulk flows, we demonstrate how equatorially mirroring electrons can travel long distances and gain hundreds of keV from betatron acceleration. The model parameters are constrained by four Time History of Events and Macroscale Interactions during Substorms satellite observations, putting limits on the DFBs' speed, location, and magnetic and electric field magnitudes. We find that the sharp, localized peaks in magnetic field have such strong spatial gradients that energetic electrons ∇B drift in closed paths around the peaks as those peaks travel earthward. This is understood in terms of the third adiabatic invariant, which remains constant when the field changes on timescales longer than the electron's drift timescale: An energetic electron encircles a sharp peak in magnetic field in a closed path subtending an area of approximately constant flux. As the flux bundle magnetic field increases the electron's drift path area shrinks and the electron is prevented from escaping to the ambient plasma sheet, while it continues to gain energy via betatron acceleration. When the flux bundles arrive at and merge with the inner magnetosphere, where the background field is strong, the electrons suddenly gain access to previously closed drift paths around the Earth. DFBs are therefore instrumental in transporting and energizing energetic electrons over long distances along the magnetotail, bringing them to the inner magnetosphere and energizing them by hundreds of keV.Plain Language SummaryScientists have wondered how narrow flow channels in space could transport and energize <span class="hlt">electrons</span> enough before the <span class="hlt">electrons</span> escape the channel. They also wondered how narrow, localized magnetic field peaks (and their electric fields) contribute to <span class="hlt">electron</span> energization in comparison to wide, large-scale electromagnetic fields. We show</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000ApJ...545..532W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000ApJ...545..532W"><span>Correlative Aspects of the Solar <span class="hlt">Electron</span> Neutrino <span class="hlt">Flux</span> and Solar Activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilson, Robert M.</p> <p>2000-12-01</p> <p>Between 1970 and 1994, the Homestake Solar Neutrino Detector obtained 108 observations of the solar <span class="hlt">electron</span> neutrino <span class="hlt">flux</span> (greater than 0.814 MeV). The ``best fit'' values derived from these observations suggest an average daily production rate of about 0.485 37Ar atom per day, a rate equivalent to about 2.6 SNU (solar neutrino units) or about a factor of 3 below the expected rate from the standard solar model. In order to explain, at least, a portion of this discrepancy, many researchers have speculated that the <span class="hlt">flux</span> of solar neutrinos is variable, possibly being correlated with certain markers of the solar cycle (specifically, sunspot number and the Ap index). Indeed, previous studies, on the basis of shorter time intervals or data averaged in particular ways, often found evidence supportive for preferential behavior between the solar neutrino <span class="hlt">flux</span> and solar activity. In this paper, using the larger ``standard data set'' and run-length-adjusted averages, the notion of preferential behavior between solar <span class="hlt">electron</span> neutrino <span class="hlt">flux</span> and solar activity is reexamined. The results clearly show that no statistically meaningful associations exist between the solar <span class="hlt">electron</span> neutrino <span class="hlt">flux</span> and any of the usual markers of solar activity, including sunspot number, the Ap index, the Deep River neutron monitor counts (cosmic rays), solar irradiance, and the number or size of solar energetic events (flares).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27256316','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27256316"><span>Reaction <span class="hlt">electronic</span> <span class="hlt">flux</span> and its role in DNA intramolecular proton transfers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Durán, Rocío; Vöhringer-Martinez, Esteban; Toro-Labbé, Alejandro; Herrera, Bárbara</p> <p>2016-06-01</p> <p>Proton transfer reactions present a key step in many biological and chemical processes. Here, we focused on the <span class="hlt">electronic</span> changes in the proton transfer reactions of the four DNA bases. In combination with the previous structural analysis the reaction <span class="hlt">electronic</span> <span class="hlt">flux</span> together with local descriptors as the Hirshfeld-I charges allow us to identify chemical events and rationalize the underlying reaction mechanism. Our results show that imine-enamine in adenine and citosyne, and keto-enol tautomerizations in thymine and guanine have different reaction mechanisms. The former involve net structural rearrangements driven by favoured electrostatic interactions between the proton and the acceptor atom whereas the keto-enol tautomerizations require <span class="hlt">electronic</span> changes reflected in the reaction <span class="hlt">electronic</span> <span class="hlt">flux</span> and changes in the NBO bond orders which favour the proton transfer reaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5340864','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5340864"><span>Integral probability of auroral <span class="hlt">electron</span> <span class="hlt">flux</span> events from SSJ/4 DMSP F9 <span class="hlt">electron</span> measurements. Interim report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hardy, D.A.; Bounar, K.H.</p> <p>1992-05-18</p> <p>A study has been completed to determine the probability of observing different levels of auroral <span class="hlt">electron</span> precipitation both within fixed spatial elements in magnetic local time and corrected geomagnetic latitude, and within spatial elements when the magnetic local time is fixed but the latitude range can be varied. The auroral <span class="hlt">electron</span> precipitation probability is defined for a series of thresholds in <span class="hlt">electron</span> average energy and <span class="hlt">electron</span> energy <span class="hlt">flux</span> as a function of geomagnetic activity. The study provides the capability to determine the probability of observation of an auroral <span class="hlt">electron</span> precipitation event for any specified threshold in average energy, energy <span class="hlt">flux</span>, and level of geomagnetic activity for any location in the auroral region or for any line of sight through the auroral region. The input for the study is one year of data from the SSJ/4 <span class="hlt">electron</span> and proton spectrometer flown on the F9 satellite of the Defense Meteorological Satellite Program (DMSP) comprising approximately 10, 141 hemispheric passes through the auroral region. The binning technique used to determine these probabilities is presented and some results are discussed. The operation of the software package to display the probability results is described. Defense Meteorological Satellite Program (DMSP), Aurora, Precipitating <span class="hlt">electrons</span>, Geomagnetic Kp index, Integral probability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355151-local-emissivity-measured-fermi-lat-implications-cosmic-ray-spectra','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355151-local-emissivity-measured-fermi-lat-implications-cosmic-ray-spectra"><span>Local H i emissivity measured with FERMI-<span class="hlt">LAT</span> and implications for Cosmic-ray spectra</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Casandjian, Jean -Marc</p> <p>2015-06-20</p> <p>Cosmic-ray (CR) <span class="hlt">electrons</span> and nuclei interact with the Galactic interstellar gas and produce high-energy γ-rays. The γ-ray emission rate per hydrogen atom, called emissivity, provides a unique indirect probe of the CR <span class="hlt">flux</span>. We present the measurement and the interpretation of the emissivity in the solar neighborhood for γ-ray energy from 50 MeV to 50 GeV. We analyzed a subset of 4 yr of observations from the Large Area Telescope (<span class="hlt">LAT</span>) aboard the Fermi Gamma-ray Space Telescope (Fermi) restricted to absolute latitudesmore » $$10^\\circ \\lt | b| \\lt 70^\\circ $$. From a fit to the <span class="hlt">LAT</span> data including atomic, molecular, and ionized hydrogen column density templates, as well as a dust optical depth map, we derived the emissivities, the molecular hydrogen–to–CO conversion factor $${X}_{\\mathrm{CO}}=(0.902\\pm 0.007)\\times {10}^{20}$$ cm–2 (K km s–1)–1, and the dust-to-gas ratio $${X}_{\\mathrm{DUST}}=(41.4\\pm 0.3)\\times {10}^{20}$$ cm–2 mag–1. Moreover, we detected for the first time γ-ray emission from ionized hydrogen. We compared the extracted emissivities to those calculated from γ-ray production cross sections and to CR spectra measured in the heliosphere. We observed that the experimental emissivities are reproduced only if the solar modulation is accounted for. This provides a direct detection of solar modulation observed previously through the anticorrelation between CR <span class="hlt">fluxes</span> and solar activity. Lastly, we fitted a parameterized spectral form to the heliospheric CR observations and to the Fermi-<span class="hlt">LAT</span> emissivity and obtained compatible local interstellar spectra for proton and helium kinetic energy per nucleon between between 1 and 100 GeV and for electron–positrons between 0.1 and 100 GeV.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/451143','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/451143"><span>Modeling of the recycling particle <span class="hlt">flux</span> and <span class="hlt">electron</span> particle transport in the DIII-D tokamak</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Baker, D.R.; Jackson, G.L.; Maingi, R.; Owen, L.W.; Porter, G.D.</p> <p>1996-10-01</p> <p>One of the most difficult aspects of performing an equilibrium particle transport analysis in a diverted tokamak is the determination of the particle <span class="hlt">flux</span> which enters the plasma after recycling from the divertor plasma, the divertor target plates or the vessel wall. An approach which has been utilized in the past is to model the edge, scrape-off layer (SOL), and divertor plasma to match measured plasma parameters and then use a neutral transport code to obtain an edge recycling <span class="hlt">flux</span> while trying to match the measured divertor D(x emissivity. Previous simulations were constrained by <span class="hlt">electron</span> density (n{sub e}) and temperature (T{sub e}), ion temperature (T{sub i}) data at the outer midplane, divertor heat <span class="hlt">flux</span> from infrared television cameras, and n{sub e}, T{sub e} and particle <span class="hlt">flux</span> at the target from fixed Langmuir probes, along with the divertor D{sub {alpha}} emissivity. In this paper, we present results of core fueling calculations from the 2-D modeling for ELM-free discharges, constrained by data from the new divertor diagnostics. In addition, we present a simple technique for estimating the recycling <span class="hlt">flux</span> just after the L-H transition and demonstrate how this technique is supported by the detailed modeling. We will show the effect which inaccuracies in the recycling <span class="hlt">flux</span> have on the calculated particle <span class="hlt">flux</span> in the plasma core. For some specific density profiles, it is possible to separate the convective <span class="hlt">flux</span> from the conductive <span class="hlt">flux</span>. The diffusion coefficients obtained show a sharp decrease near a normalized radius of 0.9 indicating the presence of a transport barrier.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...835L..35M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...835L..35M"><span>New ALMA and Fermi/<span class="hlt">LAT</span> Observations of the Large-scale Jet of PKS 0637‑752 Strengthen the Case Against the IC/CMB Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meyer, Eileen T.; Breiding, Peter; Georganopoulos, Markos; Oteo, Iván; Zwaan, Martin A.; Laing, Robert; Godfrey, Leith; Ivison, R. J.</p> <p>2017-02-01</p> <p>The Chandra X-ray observatory has discovered several dozen anomalously X-ray-bright jets associated with powerful quasars. A popular explanation for the X-ray <span class="hlt">flux</span> from the knots in these jets is that relativistic synchrotron-emitting <span class="hlt">electrons</span> inverse-Compton scatter cosmic microwave background (CMB) photons to X-ray energies (the IC/CMB model). This model predicts a high gamma-ray <span class="hlt">flux</span> that should be detectable by the Fermi/Large Area Telescope (<span class="hlt">LAT</span>) for many sources. GeV-band upper limits from Fermi/<span class="hlt">LAT</span> for the well-known anomalous X-ray jet in PKS 0637‑752 were previously shown in Meyer et al. to violate the predictions of the IC/CMB model. Previously, measurements of the jet synchrotron spectrum, important for accurately predicting the gamma-ray <span class="hlt">flux</span> level, were lacking between radio and infrared wavelengths. Here, we present new Atacama Large Millimeter/submillimeter Array (ALMA) observations of the large-scale jet at 100, 233, and 319 GHz, which further constrain the synchrotron spectrum, supporting the previously published empirical model. We also present updated limits from the Fermi/<span class="hlt">LAT</span> using the new “Pass 8” calibration and approximately 30% more time on source. With these deeper limits, we rule out the IC/CMB model at the 8.7σ level. Finally, we demonstrate that complete knowledge of the synchrotron SED is critical in evaluating the IC/CMB model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.5122S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.5122S"><span>RELEC Experiment on board Vernov Satellite: Relativistic <span class="hlt">Electron</span> <span class="hlt">Flux</span> Dynamics in Near-Earth Space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Svertilov, Sergiey</p> <p>2015-04-01</p> <p>The main goal of RELEC mission is study of magnetosphere relativistic <span class="hlt">electron</span> precipitation with it possible acting on the upper atmosphere and ionosphere as well as the monitor observation of radiation and electromagnetic environment in the near-Earth Space. The RELEC set of instruments includes two identical detectors of X- and gamma-rays of high temporal resolution and sensitivity (DRGE-1 & DRGE-2), three axe directed detectors of energetic <span class="hlt">electrons</span> and protons DRGE-3, UV TLE imager MTEL, UV detector DUV, low-frequency analyser LFA, radio-frequency analyser RFA, module of <span class="hlt">electronics</span> intended for commands and data collection BE. The small satellite now named Vernov with RELEC instruments was successfully launched July, 8 2014. The mission orbit is solar-synchronous with apogee 830 km, perigee 640 km, inclination 98.4o and orbital period about 100 min. The total data output is about 1.2 Gbyte per day. The <span class="hlt">fluxes</span> and spectra of <span class="hlt">electrons</span> in the wide energy range from 0.2 to 15 MeV are measured with the use of three detectors with axe normally directed to each other: to the local zenith, opposite to the satellite velocity vector and along the direction added two previous to the Cartesian system. Due to such detector system it is possible to estimate the <span class="hlt">electron</span> <span class="hlt">flux</span> anisotropy. The wide dynamical range from ~1 up to 104 part/cm2s and fine time resolution (~10 mcs) allows observations of trapped, quasi-trapped and precipitated <span class="hlt">electron</span> <span class="hlt">flux</span> and spectral variations in different areas in the near-Earth space including low L-shells. Comparative analysis of <span class="hlt">electron</span> <span class="hlt">fluxes</span> measured by RELEC with experimental data on <span class="hlt">electron</span> detection in the experiments on board the spacecraft Electro-L with geostationary orbit, and Meteor-M2 with 800 km altitude circular polar orbit similar to Vernov allows to reconstruct the energetic <span class="hlt">electron</span> spatial distribution in the near-Earth space. A comparison will be held for periods of moderate geomagnetic disturbances of August 26</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24b2109I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24b2109I"><span>Transport coefficients and heat <span class="hlt">fluxes</span> in non-equilibrium high-temperature flows with <span class="hlt">electronic</span> excitation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Istomin, V. A.; Kustova, E. V.</p> <p>2017-02-01</p> <p>The influence of <span class="hlt">electronic</span> excitation on transport processes in non-equilibrium high-temperature ionized mixture flows is studied. Two five-component mixtures, N 2 / N2 + / N / N + / e - and O 2 / O2 + / O / O + / e - , are considered taking into account the <span class="hlt">electronic</span> degrees of freedom for atomic species as well as the rotational-vibrational-<span class="hlt">electronic</span> degrees of freedom for molecular species, both neutral and ionized. Using the modified Chapman-Enskog method, the transport coefficients (thermal conductivity, shear viscosity and bulk viscosity, diffusion and thermal diffusion) are calculated in the temperature range 500-50 000 K. Thermal conductivity and bulk viscosity coefficients are strongly affected by <span class="hlt">electronic</span> states, especially for neutral atomic species. Shear viscosity, diffusion, and thermal diffusion coefficients are not sensible to <span class="hlt">electronic</span> excitation if the size of excited states is assumed to be constant. The limits of applicability for the Stokes relation are discussed; at high temperatures, this relation is violated not only for molecular species but also for <span class="hlt">electronically</span> excited atomic gases. Two test cases of strongly non-equilibrium flows behind plane shock waves corresponding to the spacecraft re-entry (Hermes and Fire II) are simulated numerically. Fluid-dynamic variables and heat <span class="hlt">fluxes</span> are evaluated in gases with <span class="hlt">electronic</span> excitation. In inviscid flows without chemical-radiative coupling, the flow-field is weakly affected by <span class="hlt">electronic</span> states; however, in viscous flows, their influence can be more important, in particular, on the convective heat <span class="hlt">flux</span>. The contribution of different dissipative processes to the heat transfer is evaluated as well as the effect of reaction rate coefficients. The competition of diffusion and heat conduction processes reduces the overall effect of <span class="hlt">electronic</span> excitation on the convective heating, especially for the Fire II test case. It is shown that reliable models of chemical reaction rates are of great</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930049688&hterms=Quantitative+Analysis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DQuantitative%2BAnalysis','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930049688&hterms=Quantitative+Analysis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DQuantitative%2BAnalysis"><span>Quantitative analysis of bidirectional <span class="hlt">electron</span> <span class="hlt">fluxes</span> within coronal mass ejections at 1 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Phillips, J. L.; Gosling, J. T.; Mccomas, D. J.; Bame, S. J.; Feldman, W. C.</p> <p>1992-01-01</p> <p>The solar wind <span class="hlt">electron</span> heat <span class="hlt">flux</span> is carried primarily by suprathermal <span class="hlt">electrons</span> beamed antisunward along the interplanetary magnetic field. However, analysis of <span class="hlt">electron</span> observations at 1 AU has shown that counterstreaming <span class="hlt">electron</span> beams, suggesting closed magnetic structures, prevail within coronal mass ejections (CMEs). These structures might be magnetic 'tongues', magnetically detached plasmoids, or complex <span class="hlt">flux</span> ropes. Here we show results of analysis of ISEE-3 observations within 39 CMEs, including the asymmetry between the two beams, its control by magnetic field orientation, and the variation of the <span class="hlt">electron</span> distributions as CMEs convect past the spacecraft. We find that some CMEs are strongly asymmetric, with the antisunward beam generally dominant, while others contain nearly symmetric beams. The beam asymmetries, and the magnetic field orientations, exhibit characteristic trends as CMEs pass over the spacecraft. We present an example of a distinctive 'strahl-on-strahl' distribution, suggesting continued magnetic connection to the corona, in which a narrow antisunward beam is superimposed on a broader beam. Our results favor continuing magnetic connection to the Sun in a tongue or <span class="hlt">flux</span> rope geometry rather than a fully detached plasmoid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991STIN...9216965P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991STIN...9216965P"><span>Quantitative analysis of bidirectional <span class="hlt">electron</span> <span class="hlt">fluxes</span> within coronal mass ejections at 1 AU</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Phillips, J. L.; Gosling, J. T.; McComas, D. J.; Bame, S. J.; Feldman, W. C.</p> <p></p> <p>The solar wind <span class="hlt">electron</span> heat <span class="hlt">flux</span> is carried primarily by suprathermal 'halo' <span class="hlt">electrons</span> beamed antisunward along the interplanetary magnetic field (IMF), indicating magnetic connection to the Sun only in one direction. However, <span class="hlt">electron</span> observations at 1 AU show that counterstreaming halo beams, suggesting closed magnetic structures, prevail within coronal mass ejections (CME's). These structures might be magnetic 'tongues', tied to the Sun at both ends, magnetically detached plasmoids, or complex <span class="hlt">flux</span> rope structures. Here, we present first results of analysis of ISEE-3 observations within 39 CME's, including the asymmetry between the counterstreaming beams and its control by the IMF orientation, and the variation of the <span class="hlt">electron</span> distributions as CME's convect past the spacecraft. We find that some CME's contain nearly symmetric <span class="hlt">electron</span> beams, while others are strongly asymmetric, and that the antisunward beam is generally dominant. The more nearly radial the IMF, the greater the asymmetry between outward and inward beams. We present an example of a distinctive 'strahl-on-strahl' distribution, suggesting continued magnetic connection to the corona, in which a narrow antisunward beam is superimposed on a broader beam. Taken as a whole, our results appear to favor a tongue or <span class="hlt">flux</span> rope scenario rather than a fully detached plasmoid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20643911','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20643911"><span>The role of <span class="hlt">electron</span> heat <span class="hlt">flux</span> in guide-field magnetic reconnection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hesse, Michael; Kuznetsova, Masha; Birn, Joachim</p> <p>2004-12-01</p> <p>A combination of analytical theory and particle-in-cell simulations are employed in order to investigate the <span class="hlt">electron</span> dynamics near and at the site of guide field magnetic reconnection. A detailed analysis of the contributions to the reconnection electric field shows that both bulk inertia and pressure-based quasiviscous processes are important for the <span class="hlt">electrons</span>. Analytic scaling demonstrates that conventional approximations for the <span class="hlt">electron</span> pressure tensor behavior in the dissipation region fail, and that heat <span class="hlt">flux</span> contributions need to be accounted for. Based on the evolution equation of the heat <span class="hlt">flux</span> three tensor, which is derived in this paper, an approximate form of the relevant heat <span class="hlt">flux</span> contributions to the pressure tensor is developed, which reproduces the numerical modeling result reasonably well. Based on this approximation, it is possible to develop a scaling of the <span class="hlt">electron</span> current layer in the central dissipation region. It is shown that the pressure tensor contributions become important at the scale length defined by the <span class="hlt">electron</span> Larmor radius in the guide magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1291235-nonstorm-time-dropout-radiation-belt-electron-fluxes-september','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1291235-nonstorm-time-dropout-radiation-belt-electron-fluxes-september"><span>Nonstorm time dropout of radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 24 September 2013</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Su, Zhenpeng; Gao, Zhonglei; Reeves, Geoffrey D.; ...</p> <p>2016-07-01</p> <p>Radiation belt <span class="hlt">electron</span> <span class="hlt">flux</span> dropouts during the main phase of geomagnetic storms have received increasing attention in recent years. Here we focus on a rarely reported nonstorm time dropout event observed by Van Allen Probes on 24 September 2013. Within several hours, the radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> exhibited a significant (up to 2 orders of magnitude) depletion over a wide range of radial distances (L > 4.5), energies (~500 keV to several MeV) and equatorial pitch angles (0° ≤ αe ≤ 180°). STEERB simulations show that the relativistic <span class="hlt">electron</span> loss in the region L = 4.5–6.0 was primarily caused bymore » the pitch angle scattering of observed plasmaspheric hiss and electromagnetic ion cyclotron waves. Furthermore, our results emphasize the complexity of radiation belt dynamics and the importance of wave-driven precipitation loss even during nonstorm times.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PPNL...13.1006S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PPNL...13.1006S"><span>Acceleration of deuterons from laser plasma in direct pulsed <span class="hlt">electron</span> <span class="hlt">fluxes</span> for generation of neutrons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shikanov, A. E.; Vovchenko, E. D.; Kozlovskii, K. I.; Shatokhin, V. L.</p> <p>2016-12-01</p> <p>We report the results of experiments in which laser plasma deuterons are accelerated toward beryllium and deuterated polyethylene targets in a drift tube by means of a direct pulsed <span class="hlt">flux</span> of <span class="hlt">electrons</span> accelerated to maximum energy of 250 keV. Neutrons produced as a result of the interaction of deuterons with the targets are detected. The yield of neutrons in some of the experimental series reaches 106 n/pulse. Using a pulsed magnetic field synchronized with the generation of laser plasma is proposed for increasing the neutron yield as a result of <span class="hlt">electron</span> <span class="hlt">flux</span> compression. This magnetic field in the drift region of <span class="hlt">electrons</span> is created by a spiral coil of conical shape.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1291235','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1291235"><span>Nonstorm time dropout of radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 24 September 2013</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Su, Zhenpeng; Gao, Zhonglei; Reeves, Geoffrey D.; Funsten, Herbert O.; Zhu, Hui; Li, Wen; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; Baker, D. N.; Blake, J. B.; Wygant, J. R.</p> <p>2016-07-01</p> <p>Radiation belt <span class="hlt">electron</span> <span class="hlt">flux</span> dropouts during the main phase of geomagnetic storms have received increasing attention in recent years. Here we focus on a rarely reported nonstorm time dropout event observed by Van Allen Probes on 24 September 2013. Within several hours, the radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> exhibited a significant (up to 2 orders of magnitude) depletion over a wide range of radial distances (<i>L</i> > 4.5), energies (~500 keV to several MeV) and equatorial pitch angles (0° ≤ α<sub>e</sub> ≤ 180°). STEERB simulations show that the relativistic <span class="hlt">electron</span> loss in the region L = 4.5–6.0 was primarily caused by the pitch angle scattering of observed plasmaspheric hiss and electromagnetic ion cyclotron waves. Furthermore, our results emphasize the complexity of radiation belt dynamics and the importance of wave-driven precipitation loss even during nonstorm times.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.6400S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.6400S"><span>Nonstorm time dropout of radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 24 September 2013</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Su, Zhenpeng; Gao, Zhonglei; Zhu, Hui; Li, Wen; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; Reeves, G. D.; Baker, D. N.; Blake, J. B.; Funsten, H. O.; Wygant, J. R.</p> <p>2016-07-01</p> <p>Radiation belt <span class="hlt">electron</span> <span class="hlt">flux</span> dropouts during the main phase of geomagnetic storms have received increasing attention in recent years. Here we focus on a rarely reported nonstorm time dropout event observed by Van Allen Probes on 24 September 2013. Within several hours, the radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> exhibited a significant (up to 2 orders of magnitude) depletion over a wide range of radial distances (L > 4.5), energies (˜500 keV to several MeV) and equatorial pitch angles (0°≤αe≤180°). STEERB simulations show that the relativistic <span class="hlt">electron</span> loss in the region L = 4.5-6.0 was primarily caused by the pitch angle scattering of observed plasmaspheric hiss and electromagnetic ion cyclotron waves. Our results emphasize the complexity of radiation belt dynamics and the importance of wave-driven precipitation loss even during nonstorm times.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1291235','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1291235"><span>Nonstorm time dropout of radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 24 September 2013</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Su, Zhenpeng; Gao, Zhonglei; Reeves, Geoffrey D.; Funsten, Herbert O.; Zhu, Hui; Li, Wen; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; Baker, D. N.; Blake, J. B.; Wygant, J. R.</p> <p>2016-07-01</p> <p>Radiation belt <span class="hlt">electron</span> <span class="hlt">flux</span> dropouts during the main phase of geomagnetic storms have received increasing attention in recent years. Here we focus on a rarely reported nonstorm time dropout event observed by Van Allen Probes on 24 September 2013. Within several hours, the radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> exhibited a significant (up to 2 orders of magnitude) depletion over a wide range of radial distances (<i>L</i> > 4.5), energies (~500 keV to several MeV) and equatorial pitch angles (0° ≤ α<sub>e</sub> ≤ 180°). STEERB simulations show that the relativistic <span class="hlt">electron</span> loss in the region L = 4.5–6.0 was primarily caused by the pitch angle scattering of observed plasmaspheric hiss and electromagnetic ion cyclotron waves. Furthermore, our results emphasize the complexity of radiation belt dynamics and the importance of wave-driven precipitation loss even during nonstorm times.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPSC...10..224G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPSC...10..224G"><span>The Mars aurora: UV detections and in situ <span class="hlt">electron</span> <span class="hlt">flux</span> measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gérard, J.-C.; Soret, L.; Lundin, R.; Libert, L.; Stiepen, A.; Radioti, A.; Bertaux, J.-L.; Shematovich, V. I.; Bisikalo, D.</p> <p>2015-10-01</p> <p>A detailed search through the database of the SPICAM instrument on board Mars Express made it possible to identify 16 signatures of the CO Cameron and CO2+ doublet auroral emissions. These auroral UV signatures are all located in the southern hemisphere in the vicinity of the statistical boundary between open and closed field lines. The energy spectrum of the energetic <span class="hlt">electrons</span> was simultaneously measured by ASPERA-3/ELS at higher altitude. The UV aurora is generally shifted from the region of enhanced downward <span class="hlt">electron</span> energy <span class="hlt">flux</span> by a few to several tens of degrees of latitude, suggesting that precipitation occurs in magnetic cusp like structures along inclined magnetic field lines. The ultraviolet brightness shows no proportionality with the <span class="hlt">electron</span> <span class="hlt">flux</span> measured at the spacecraft altitude. The Mars aurora appears as a sporadic short-lived feature. Results of Monte Carlo simulations will be compared with the observed brightness of the Cameron and CO2+ bands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AIPC.1357..205R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AIPC.1357..205R"><span>The Fermi <span class="hlt">LAT</span> Pulsars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Romani, Roger W.</p> <p>2011-08-01</p> <p>The Large Area Telescope on the Fermi satellite is an impressive pulsar discovery machine, with over 75 pulse detections and counting. The populations of radio-selected, γ-selected and millisecond pulsars are now large enough to display observational patterns in the light curves and luminosities. These patterns are starting to teach us about the physics of the emission zone, which seems dominated by open field lines near the speed of light cylinder. The sample also provides initial inferences about the pulsar population. Apparently a large fraction of neutron stars have a young energetic γ-ray emitting phase, making these objects a good probe of massive star evolution. The long-lived millisecond γ-ray pulsars are even more ubiquitous and may produce a significant fraction of the γ-ray background. In any event, it is clear that the present <span class="hlt">LAT</span> pulsar sample is dominated by nearby objects, and there is every expectation that the number, and quality, of pulsar detections will increase in years to come.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CP....482..146J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CP....482..146J"><span>Quantum control of <span class="hlt">electronic</span> <span class="hlt">fluxes</span> during adiabatic attosecond charge migration in degenerate superposition states of benzene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jia, Dongming; Manz, Jörn; Paulus, Beate; Pohl, Vincent; Tremblay, Jean Christophe; Yang, Yonggang</p> <p>2017-01-01</p> <p>We design four linearly x- and y-polarized as well as circularly right (+) and left (-) polarized, resonant π / 2 -laser pulses that prepare the model benzene molecule in four different degenerate superposition states. These consist of equal (0.5) populations of the <span class="hlt">electronic</span> ground state S0 (1A1g) plus one of four degenerate excited states, all of them accessible by dipole-allowed transitions. Specifically, for the molecule aligned in the xy-plane, these excited states include different complex-valued linear combinations of the 1E1u,x and 1E1u,y degenerate states. As a consequence, the laser pulses induce four different types of periodic adiabatic attosecond (as) charge migrations (AACM) in benzene, all with the same period, 504 as, but with four different types of angular <span class="hlt">fluxes</span>. One of the characteristic differences of these <span class="hlt">fluxes</span> are the two angles for zero <span class="hlt">fluxes</span>, which appear as the instantaneous angular positions of the "source" and "sink" of two equivalent, or nearly equivalent branches of the <span class="hlt">fluxes</span> which flow in pincer-type patterns from one molecular site (the "source") to the opposite one (the "sink"). These angles of zero <span class="hlt">fluxes</span> are either fixed at the positions of two opposite carbon nuclei in the yz-symmetry plane, or at the centers of two opposite carbon-carbon bonds in the xz-symmetry plane, or the angles of zero <span class="hlt">fluxes</span> rotate in angular forward (+) or backward (-) directions, respectively. As a resume, our quantum model simulations demonstrate quantum control of the <span class="hlt">electronic</span> <span class="hlt">fluxes</span> during AACM in degenerate superposition states, in the attosecond time domain, with the laser polarization as the key knob for control.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9236E..1AV','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9236E..1AV"><span>Do <span class="hlt">electron</span> <span class="hlt">flux</span> and solar x-ray in juxtaposition prior a seismic event make signature?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Verma, Umesh Prasad; Sinha, Madhurendra Nath</p> <p>2014-09-01</p> <p>Variation in the trend of <span class="hlt">electron</span> <span class="hlt">flux</span> graph in the ionosphere on the global map is common with respect to proton <span class="hlt">flux</span> variation in inverse manner seen on diurnal basis. Continuous observation connected with the NOAA , IPS and SOHO satellite respectively of USA, Australia ,Japan and India have revealed the facts remarkably peculiar and interesting trend other than usual graph of <span class="hlt">Electron</span> <span class="hlt">flux</span> and solar x-ray decrease in peak level immediate prior a seismic event. An observation recorded in juxtaposition the trend of correlation establishes this fact. This typify the events like Iran 14th April, China 17th April 2013, with 7.8 and 7.3 MW, New Zealand 6.8 MW on 16th August 2013, Pakistan 7.8 Mw and 6.8 Mw respectively on25th September, and 26th September'2013 are the supportive illustrations to the concluding concepts. The trend is also observed during the solar coronal mass ejection event. Events occur deceptively quite similar to the pre seismicity. Its diagnostic distinction can be made with the solar data available by SWPC (Australia) forecasting for solar prominences data prediction and forecasting tool. Most of the seismic phenomena are the diagnostic preseismic phenomena as the <span class="hlt">electron</span> <span class="hlt">flux</span> anomaly mechanism and principle clarify on the basis of fundamental laws of electrostatics and Maxwell equation of electromagnetic wave theory. This may prove a precursory tool in the seismic event forecasting and prediction technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19269096','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19269096"><span>Imaging <span class="hlt">flux</span> vortices in type II superconductors with a commercial transmission <span class="hlt">electron</span> microscope.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Loudon, J C; Midgley, P A</p> <p>2009-05-01</p> <p><span class="hlt">Flux</span> vortices in superconductors can be imaged using transmission <span class="hlt">electron</span> microscopy because the <span class="hlt">electron</span> beam is deflected by the magnetic <span class="hlt">flux</span> associated with the vortices. This technique has a better spatial and temporal resolution than many other imaging techniques and is sensitive to the magnetic <span class="hlt">flux</span> density within each vortex, not simply the fields at the sample surface. Despite these advantages, only two groups have successfully employed the technique using specially adapted instruments. Here we demonstrate that vortices can be imaged with a modern, commercial transmission <span class="hlt">electron</span> microscope operating at 300kV equipped with a field emission gun, Lorentz lens and a liquid helium cooled sample holder. We introduce superconductivity for non-specialists and discuss techniques for simulating and optimising images of <span class="hlt">flux</span> vortices. Sample preparation is discussed in detail as the main difficulty with the technique is the requirement for samples with very large (>10microm), flat areas so that the image is not dominated by diffraction contrast. We have imaged vortices in superconducting Bi(2)Sr(2)CaCu(2)O(8-delta) and use correlation functions to investigate the ordered arrangements they adopt as a function of applied magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000074664&hterms=neutrino&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dneutrino','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000074664&hterms=neutrino&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dneutrino"><span>Correlative Aspects of the Solar <span class="hlt">Electron</span> Neutrino <span class="hlt">Flux</span> and Solar Activity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, Robert M.</p> <p>2000-01-01</p> <p>Between 1970 and 1994, the Homestake Solar Neutrino Detector obtained 108 observations of the solar <span class="hlt">electron</span> neutrino <span class="hlt">flux</span> (less than 0.814 MeV). The "best fit" values derived from these observations suggest an average daily production rate of about 0.485 Ar-37 atom per day, a rate equivalent to about 2.6 SNU (solar neutrino units) or about a factor of 3 below the expected rate from the standard solar model. In order to explain, at least, a portion of this discrepancy, some researchers have speculated that the <span class="hlt">flux</span> of solar neutrinos is variable, possibly being correlated with various markers of the solar cycle (e.g., sunspot number, the Ap index, etc.). In this paper, using the larger "standard data set," the issue of correlative behavior between solar <span class="hlt">electron</span> neutrino <span class="hlt">flux</span> and solar activity is re-examined. The results presented here clearly indicate that no statistically significant association exists between any of the usual markers of solar activity and the solar <span class="hlt">electron</span> neutrino <span class="hlt">flux</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SpWea..15..917M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SpWea..15..917M"><span>Extreme relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the Earth's outer radiation belt: Analysis of INTEGRAL IREM data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meredith, Nigel P.; Horne, Richard B.; Sandberg, Ingmar; Papadimitriou, Constantinos; Evans, Hugh D. R.</p> <p>2017-07-01</p> <p>Relativistic <span class="hlt">electrons</span> (E > 500 keV) cause internal charging and are an important space weather hazard. To assess the vulnerability of the satellite fleet to these so-called "killer" <span class="hlt">electrons</span>, it is essential to estimate reasonable worst cases, and, in particular, to estimate the <span class="hlt">flux</span> levels that may be reached once in 10 and once in 100 years. In this study we perform an extreme value analysis of the relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the Earth's outer radiation belt as a function of energy and L∗. We use data from the Radiation Environment Monitor (IREM) on board the International Gamma Ray Astrophysical Laboratory (INTEGRAL) spacecraft from 17 October 2002 to 31 December 2016. The 1 in 10 year <span class="hlt">flux</span> at L∗=4.5, representative of equatorial medium Earth orbit, decreases with increasing energy ranging from 1.36 × 107 cm-2 s-1 sr-1 MeV-1 at E = 0.69 MeV to 5.34 × 105 cm-2 s-1 sr-1 MeV-1 at E = 2.05 MeV. The 1 in 100 year <span class="hlt">flux</span> at L∗=4.5 is generally a factor of 1.1 to 1.2 larger than the corresponding 1 in 10 year <span class="hlt">flux</span>. The 1 in 10 year <span class="hlt">flux</span> at L∗=6.0, representative of geosynchronous orbit, decreases with increasing energy ranging from 4.35 × 106 cm-2 s-1 sr-1 MeV-1 at E = 0.69 MeV to 1.16 × 105 cm-2 s-1 sr-1 MeV-1 at E = 2.05 MeV. The 1 in 100 year <span class="hlt">flux</span> at L∗=6.0 is generally a factor of 1.1 to 1.4 larger than the corresponding 1 in 10 year <span class="hlt">flux</span>. The ratio of the 1 in 10 year <span class="hlt">flux</span> at L∗=4.5 to that at L∗=6.0 increases with increasing energy ranging from 3.1 at E = 0.69 MeV to 4.6 at E = 2.05 MeV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSM51A2518S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSM51A2518S"><span>Calibrating MMS <span class="hlt">Electron</span> Drift Instrument (EDI) Ambient <span class="hlt">Electron</span> <span class="hlt">Flux</span> Measurements and Characterizing 3D Electric Field Signatures of Magnetic Reconnection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shuster, J. R.; Torbert, R. B.; Vaith, H.; Argall, M. R.; Li, G.; Chen, L. J.; Ergun, R. E.; Lindqvist, P. A.; Marklund, G. T.; Khotyaintsev, Y. V.; Russell, C. T.; Magnes, W.; Le Contel, O.; Pollock, C. J.; Giles, B. L.</p> <p>2015-12-01</p> <p>The <span class="hlt">electron</span> drift instruments (EDIs) onboard each MMS spacecraft are designed with large geometric factors (~0.01cm2 str) to facilitate detection of weak (~100 nA) <span class="hlt">electron</span> beams fired and received by the two gun-detector units (GDUs) when EDI is in its "electric field mode" to determine the local electric and magnetic fields. A consequence of the large geometric factor is that "ambient mode" <span class="hlt">electron</span> <span class="hlt">flux</span> measurements (500 eV <span class="hlt">electrons</span> having 0°, 90°, or 180° pitch angle) can vary depending on the orientation of the EDI instrument with respect to the magnetic field, a nonphysical effect that requires a correction. Here, we present determinations of the θ- and ø-dependent correction factors for the eight EDI GDUs, where θ (ø) is the polar (azimuthal) angle between the GDU symmetry axis and the local magnetic field direction, and compare the corrected <span class="hlt">fluxes</span> with those measured by the fast plasma instrument (FPI). Using these corrected, high time resolution (~1,000 samples per second) ambient <span class="hlt">electron</span> <span class="hlt">fluxes</span>, combined with the unprecedentedly high resolution 3D electric field measurements taken by the spin-plane and axial double probes (SDP and ADP), we are equipped to accurately detect <span class="hlt">electron</span>-scale current layers and electric field waves associated with the non-Maxwellian (anisotropic and agyrotropic) particle distribution functions predicted to exist in the reconnection diffusion region. We compare initial observations of the diffusion region with distributions and wave analysis from PIC simulations of asymmetric reconnection applicable for modeling reconnection at the Earth's magnetopause, where MMS will begin Science Phase 1 as of September 1, 2015.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFMSM41C0583N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFMSM41C0583N"><span>Mechanisms of the outer radiation belt <span class="hlt">electron</span> <span class="hlt">flux</span> variation during magnetic storms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakamura, M.; Obara, T.; Koshiishi, H.; Koga, K.; Matsumoto, H.; Goka, T.</p> <p>2003-12-01</p> <p>We have investigated variations of the energetic <span class="hlt">electron</span> <span class="hlt">flux</span> (> 0.4 MeV) and the magnetic field in the outer radiation belt obtained from the Standard DOse Monitor (SDOM) and the MAgnetoMeter (MAM) of the Space Environment Data Acquisition equipment (SEDA) onboard Tsubasa (Mission Demonstration Test Satellite (MDS)-1). Since Tsubasa operates in geostationary transfer orbit (GTO) with an orbital period of 10 hours and an inclination of 28.5 degrees, it has provided a rare opportunity for directly observing near-equatorial radiation belt plasma particles and the magnetic field during magnetic storms. The decreases of the energetic <span class="hlt">electron</span> <span class="hlt">flux</span> during the main phase of the magnetic storms, and the subsequent recoveries and enhancements during the recovery phase in the outer radiation belt are linked respectively to typical variations of the magnetic field. At the moment that the outer radiation belt <span class="hlt">flux</span> sharply drops during the main phase of the 17 April 2002 magnetic storm, the butterfly distribution is observed at L=5 and the magnetic equator where the magnitude of magnetic field is much smaller than the IGRF model. Calculating the drift motions of the energetic <span class="hlt">electrons</span> in the Tyganenko 2001 magnetospheric magnetic field model, shows that the drift-shell splitting mechanism could generate the butterfly distribution due to loss of the near-equatorially mirroring <span class="hlt">electrons</span> through dayside magnetopause boundary. We evaluate roles and contributions of the other possible mechanisms to explain the <span class="hlt">flux</span> decreases. We discuss the three-dimensional field configuration in the magnetopause to compare with the low earth orbital observation of the outer radiation belt <span class="hlt">flux</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSMSM51A..06M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSMSM51A..06M"><span>Effects of <span class="hlt">Electron</span> Pressure Tensor and Heat <span class="hlt">Flux</span> on Magnetic Reconnection from PIC and Hybrid Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Main, D. S.; Yin, L.; Winske, D.</p> <p>2007-05-01</p> <p>Thin current sheets lead to rapid magnetic reconnection and conversion of magnetic energy to particle energy. Two-dimensional (2D) simulations performed with different physical models and an initial planar current sheet (the GEM and Newton challenge studies) showed similar fast reconnection rates. In this paper, we discuss in detail simulations of 2D reconnection carried out with a full particle-in-cell (PIC) code and a hybrid (particle ions, massless fluid <span class="hlt">electrons</span>) code that was part of the Challenge study (Birn et al., GRL, 32, L06105, 2005). In the hybrid code, the <span class="hlt">electron</span> model contains the full <span class="hlt">electron</span> pressure tensor in the <span class="hlt">electron</span> momentum equation to break the frozen-in condition. We compare quantitatively the effects of the <span class="hlt">electron</span> pressure tensor in the two types of simulations and show both how they evolve in time and where in the thin current sheet the <span class="hlt">electron</span> off-diagonal pressure tensor terms become important. In addition, we make quantitative comparisons between reconnection rates and flow velocities obtained from the two codes. It is still an open question how best to evolve the pressure tensor and include the effects of <span class="hlt">electron</span> heat <span class="hlt">flux</span> in the hybrid model. The evolution equation for the pressure tensor has several terms and the effects of some of these terms on the reconnection dynamics will be examined. In particular, PIC simulations will be used to examine the role of heat <span class="hlt">flux</span> in reconnection events in the absence of a guide field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110023417','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110023417"><span>On the Relationship Between High Speed Solar Wind Streams and Radiation Belt <span class="hlt">Electron</span> <span class="hlt">Fluxes</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zheng, Yihua</p> <p>2011-01-01</p> <p>Both past and recent research results indicate that solar wind speed has a close connection to radiation belt <span class="hlt">electron</span> <span class="hlt">fluxes</span> [e.g., Paulikas and Blake, 1979; Reeves et aI., 2011]: a higher solar wind speed is often associated with a higher level of radiation <span class="hlt">electron</span> <span class="hlt">fluxes</span>. But the relationship can be very complex [Reeves et aI., 2011]. The study presented here provides further corroboration of this viewpoint by emphasizing the importance of a global perspective and time history. We find that all the events during years 2010 and 2011 where the >0.8 MeV integral <span class="hlt">electron</span> <span class="hlt">flux</span> exceeds 10(exp 5) particles/sq cm/sr/s (pfu) at GEO orbit are associated with the high speed streams (HSS) following the onset of the Stream Interaction Region (SIR), with most of them belonging to the long-lasting Corotating Interaction Region (CIR). Our preliminary results indicate that during HSS events, a maximum speed of 700 km/s and above is a sufficient but not necessary condition for the > 0.8 MeV <span class="hlt">electron</span> <span class="hlt">flux</span> to reach 10(exp 5) pfu. But in the exception cases of HSS events where the <span class="hlt">electron</span> <span class="hlt">flux</span> level exceeds the 10(exp 5) pfu value but the maximum solar wind speed is less than 700 km/s, a prior impact can be noted either from a CME or a transient SIR within 3-4 days before the arrival of the HSS - stressing the importance of time history. Through superposed epoch analysis and studies providing comparisons with the CME events and the HSS events where the <span class="hlt">flux</span> level fails to reach the 10(exp 5) pfu, we will present the quantitative assessment of behaviors and relationships of various quantities, such as the time it takes to reach the <span class="hlt">flux</span> threshold value from the stream interface and its dependence on different physical parameters (e.g., duration of the HSS event, its maximum or average of the solar wind speed, IMF Bz, Kp). The ultimate goal is to apply what is derived to space weather forecasting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19740035641&hterms=volt&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dvolt','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19740035641&hterms=volt&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dvolt"><span>Observations of the nighttime <span class="hlt">electron</span> volt range <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the equatorial region</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rao, B. C. N.; Singh, R.; Maier, E. J.</p> <p>1974-01-01</p> <p>The importance of some of the features observed among the nighttime equatorial data of Explorer 31 is discussed with respect to the nighttime thermal structure of the topside ionosphere. The very short-lived photoelectrons being absent, the nighttime measurements represent the background <span class="hlt">flux</span> due to magnetospheric particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19740035641&hterms=volt&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dvolt','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19740035641&hterms=volt&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dvolt"><span>Observations of the nighttime <span class="hlt">electron</span> volt range <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the equatorial region</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rao, B. C. N.; Singh, R.; Maier, E. J.</p> <p>1974-01-01</p> <p>The importance of some of the features observed among the nighttime equatorial data of Explorer 31 is discussed with respect to the nighttime thermal structure of the topside ionosphere. The very short-lived photoelectrons being absent, the nighttime measurements represent the background <span class="hlt">flux</span> due to magnetospheric particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3004523','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3004523"><span>LAB/NTAL/<span class="hlt">Lat</span>2: a force to be reckoned with in all leukocytes?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Orr, Selinda J.; McVicar, Daniel W.</p> <p>2011-01-01</p> <p>LAB/NTAL/<span class="hlt">Lat</span>2 is a transmembrane adaptor protein closely related to <span class="hlt">LAT</span>. It is expressed in various myeloid and lymphoid cells, many of which also express <span class="hlt">LAT</span>. Phosphorylation of LAB occurs following engagement of various ITAM- and non-ITAM-linked receptors and can play positive and negative roles following receptor engagement. <span class="hlt">LAT</span> binds PLCγ directly, resulting in efficient Ca2+ <span class="hlt">flux</span> and degranulation. However, LAB does not contain a PLCγ-binding motif and only binds PLCγ indirectly, possibly via Grb2, thereby resulting in suboptimal signaling. As <span class="hlt">LAT</span> can signal more efficiently than LAB, competition between the 2 for space/substrates in the lipid rafts can attenuate signaling. This competition model requires coexpression of <span class="hlt">LAT</span>; however, LAB is repressive, even in cells lacking substantial <span class="hlt">LAT</span> expression such as macrophages and mature B cells. The reported interaction between LAB and the ubiquitin E3-ligase c-Cbl suggests 1 possible mechanism for <span class="hlt">LAT</span>-independent inhibition by LAB, but such a model requires further investigation. Given the wide-reaching expression pattern of LAB, LAB has the ability to modulate signaling in virtually every type of leukocyte. Regardless of its ultimate mode of action, the potent regulatory capability of LAB proves this protein to be a complex adaptor that warrants continued, substantial scrutiny by biochemists and immunologists alike. PMID:20643813</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20643813','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20643813"><span>LAB/NTAL/<span class="hlt">Lat</span>2: a force to be reckoned with in all leukocytes?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Orr, Selinda J; McVicar, Daniel W</p> <p>2011-01-01</p> <p>LAB/NTAL/<span class="hlt">Lat</span>2 is a transmembrane adaptor protein closely related to <span class="hlt">LAT</span>. It is expressed in various myeloid and lymphoid cells, many of which also express <span class="hlt">LAT</span>. Phosphorylation of LAB occurs following engagement of various ITAM- and non-ITAM-linked receptors and can play positive and negative roles following receptor engagement. <span class="hlt">LAT</span> binds PLCγ directly, resulting in efficient Ca²+ <span class="hlt">flux</span> and degranulation. However, LAB does not contain a PLCγ-binding motif and only binds PLCγ indirectly, possibly via Grb2, thereby resulting in suboptimal signaling. As <span class="hlt">LAT</span> can signal more efficiently than LAB, competition between the 2 for space/substrates in the lipid rafts can attenuate signaling. This competition model requires coexpression of <span class="hlt">LAT</span>; however, LAB is repressive, even in cells lacking substantial <span class="hlt">LAT</span> expression such as macrophages and mature B cells. The reported interaction between LAB and the ubiquitin E3-ligase c-Cbl suggests 1 possible mechanism for <span class="hlt">LAT</span>-independent inhibition by LAB, but such a model requires further investigation. Given the wide-reaching expression pattern of LAB, LAB has the ability to modulate signaling in virtually every type of leukocyte. Regardless of its ultimate mode of action, the potent regulatory capability of LAB proves this protein to be a complex adaptor that warrants continued, substantial scrutiny by biochemists and immunologists alike.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM41E..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM41E..01M"><span>High time-resolution <span class="hlt">electron</span> energy and <span class="hlt">flux</span> estimates inside regions of flickering and pulsating aurora</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Michell, R.; Samara, M.; Grubbs, G. A., II</p> <p>2016-12-01</p> <p>The temporal fluctuations within the aurora can vary over vastly different timescales, indicating different generation mechanisms. Fluctuating aurora best describes two main types of aurora, commonly referred to as flickering aurora and pulsating aurora. These two types of aurora contain temporal fluctuations that vary from being periodic to semi-periodic to nearly random and covering timescales of 20 Hz to minutes. High-resolution multi-spectral auroral imaging is used to compute emission line ratios that can be used in combination with <span class="hlt">electron</span> transport modeling in order to estimate the average energy and total energy <span class="hlt">flux</span> of the precipitating <span class="hlt">electrons</span>. The auroral imaging used here was recorded at a rate of 40 frames per second, with energy and <span class="hlt">flux</span> estimates made at each frame, enabling unprecedented time resolution for examining the precipitating <span class="hlt">electron</span> characteristics within these fluctuations. The variations in the total energy <span class="hlt">flux</span> and average energy of the precipitating <span class="hlt">electrons</span> will be compared to the phase of the optical auroral cycle, in order to gain insight into the generation processes creating the fluctuating cycles. The emphasis of this talk will be on using these techniques to gain insight into the outstanding questions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820047461&hterms=Electron+Transfer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DElectron%2BTransfer','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820047461&hterms=Electron+Transfer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DElectron%2BTransfer"><span>Energetic protons, alpha particles, and <span class="hlt">electrons</span> in magnetic <span class="hlt">flux</span> transfer events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scholer, M.; Hovestadt, D.; Ipavich, F. M.; Gloeckler, G.</p> <p>1982-01-01</p> <p>Energetic proton, alpha particle, and <span class="hlt">electron</span> data are presented for two magnetopause crossings, which show magnetic field signatures characteristic of <span class="hlt">flux</span> transfer events (FTEs). Energetic proton and alpha particles are observed streaming along the magnetic field within the magnetosheath in all events showing magnetic signatures characteristic of the FTEs. <span class="hlt">Flux</span> ratios as high as about 180 parallel and antiparallel to the magnetic field are observed, which means that ions of about 30 keV per charge are at times streaming almost scatter-free from the magnetopause into the magnetosheath. Energetic ion bursts with signatures equal to those observed in FTEs are reduced by more than an order of magnitude as compared to the trapped particle <span class="hlt">flux</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992PhDT.......136G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992PhDT.......136G"><span><span class="hlt">Flux</span> Pinning Phenomena in <span class="hlt">Electron</span> Irradiated Yttrium BARIUM(2) COPPER(3) OXYGEN(7-DELTA) Single Crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Giapintzakis, John Konstantinos</p> <p>1992-01-01</p> <p>It has been shown that 1 MeV <span class="hlt">electron</span> irradiation to a typical dose Phi~ 1times 10^{19} cm^{ -2} results in an enhancement of the critical current density in twinned and untwinned YBa_2 Cu_3O_{7 -delta} single crystals. Values up to two times the preirradiation J_{c} at 10 K and 1 T are observed. The J _{c} enhancement is accompanied by a dramatic increase of the irreversibility field. A threshold incident <span class="hlt">electron</span> energy (E_{ t}~ 0.5 MeV) is found above which <span class="hlt">flux</span> pinning enhancement is observed. The data indicated that the <span class="hlt">electron</span> radiation-induced defects are effective pinning centers only for the orientation H parallel c-axis. In-situ TEM studies in the HVEM suggest that the pinning centers must be smaller than 20 A. A comparison of the <span class="hlt">electron</span> irradiation results with those of proton irradiation experiments indicate a lower magnitude of enhancement of J_{c} at 10 K and 2 T for the <span class="hlt">electron</span> case. The probable explanation is the difference in the energy spectra of the PKAs produced by the two types of irradiation. GdBa_2Cu_3O_{7-delta } and EuBa_2Cu_3O _{7-delta} single crystals irradiated with 0.6 MeV <span class="hlt">electrons</span> displayed similar <span class="hlt">flux</span> pinning enhancements as YBa_2Cu _3O_{7-delta} crystals, indicating that Y displacements are not primary <span class="hlt">flux</span> pinners. The evidence from annealing studies suggests that the primary pinning center produced by the <span class="hlt">electron</span> irradiation is not associated with the oxygen in the Cu-O chains. Instead, a consistent interpretation of the data suggests that the primary pinning defect is most likely based on the displacement of a copper atom from the CuO_2 plane. In order to account for the complete enhancement of J_{c} other pinning mechanisms aside from point defects, such as small point defect clusters, should be considered.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJS..224....8A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJS..224....8A"><span>The First Fermi <span class="hlt">LAT</span> Supernova Remnant Catalog</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Acero, F.; Ackermann, M.; Ajello, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Brandt, T. J.; Bregeon, J.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caputo, R.; Caragiulo, M.; Caraveo, P. A.; Casandjian, J. M.; Cavazzuti, E.; Cecchi, C.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen, J. M.; Cohen-Tanugi, J.; Cominsky, L. R.; Condon, B.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Venere, L.; Drell, P. S.; Drlica-Wagner, A.; Favuzzi, C.; Ferrara, E. C.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Gomez-Vargas, G. A.; Grenier, I. A.; Grondin, M.-H.; Guillemot, L.; Guiriec, S.; Gustafsson, M.; Hadasch, D.; Harding, A. K.; Hayashida, M.; Hays, E.; Hewitt, J. W.; Hill, A. B.; Horan, D.; Hou, X.; Iafrate, G.; Jogler, T.; Jóhannesson, G.; Johnson, A. S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Katsuta, J.; Kerr, M.; Knödlseder, J.; Kocevski, D.; Kuss, M.; Laffon, H.; Lande, J.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Magill, J.; Maldera, S.; Marelli, M.; Mayer, M.; Mazziotta, M. N.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Moiseev, A. A.; Monzani, M. E.; Moretti, E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nemmen, R.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Petrosian, V.; Piron, F.; Pivato, G.; Porter, T. A.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Renaud, M.; Reposeur, T.; Rousseau, R.; Saz Parkinson, P. M.; Schmid, J.; Schulz, A.; Sgrò, C.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Strong, A. W.; Suson, D. J.; Tajima, H.; Takahashi, H.; Tanaka, T.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Tibolla, O.; Torres, D. F.; Tosti, G.; Troja, E.; Uchiyama, Y.; Vianello, G.; Wells, B.; Wood, K. S.; Wood, M.; Yassine, M.; den Hartog, P. R.; Zimmer, S.</p> <p>2016-05-01</p> <p>To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the Fermi Large Area Telescope (<span class="hlt">LAT</span>). Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 <span class="hlt">flux</span> upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi <span class="hlt">LAT</span> analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, we demonstrate the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. We model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23415834','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23415834"><span>Low-<span class="hlt">flux</span> <span class="hlt">electron</span> diffraction study for the intercellular lipid organization on a human corneocyte.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nakazawa, Hiromitsu; Imai, Tomohiro; Hatta, Ichiro; Sakai, Shingo; Inoue, Shintaro; Kato, Satoru</p> <p>2013-06-01</p> <p>Human skin stratum corneum (SC) structures were investigated by <span class="hlt">electron</span> diffraction (ED) with a very low-<span class="hlt">flux</span> <span class="hlt">electron</span> beam with the help of high-sensitivity detectors, the imaging plate and the CCD camera. This low-<span class="hlt">flux</span> <span class="hlt">electron</span> diffraction (LFED) method made it possible to minimize the unfavorable effect of <span class="hlt">electron</span> beam damage and to give a reliable diffraction pattern from a small selected area (0.2μm(2)) on a corneocyte. Dependence of the 2-dimensional ED pattern on the size of the selected area showed that orientational correlation between lipid packing domains can persist over the area much larger than their domain size. The LFED method also allowed us to trace the detailed structural change induced by the <span class="hlt">electron</span> beam damage. The ED diffraction peak for the lattice constant of about 4.1nm decayed in three steps. The detailed analysis of these three steps suggested that a different type of orthorhombic structure exists interacted with the well-described hexagonal and orthorhombic structures, in the process of decay resulting from <span class="hlt">electron</span> beam damage. Copyright © 2013 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.5275L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.5275L"><span>Can the <span class="hlt">electron</span> heat <span class="hlt">flux</span> at 1 AU be collisional ? Results from kinetic simulations.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Landi, Simone; Pantellini, Filippo; Matteini, Lorenzo</p> <p>2014-05-01</p> <p>Recent results using statistically significant data of the solar wind at 1AU (see Bale et al. ApJL 769:L22, 2013) have shown that when the thermal Knudsen number, the ratio between the <span class="hlt">electron</span> mean free path and the temperature scale height, falls below ~0.3, the <span class="hlt">electron</span> heat <span class="hlt">flux</span> Q does rapidly approach the classical collisional Spitzer-Harm limit Q_SH ~ T5/2 dT/dr, where T is the temperature and r the heliocentric distance. This experimental finding seems to contradict a number of theoretical works which suggest that the collisional expression for the heat <span class="hlt">flux</span> is only guaranteed for Knudsen numbers smaller than ~0.001 (e.g. Shoub ApJ, 266, 339-369, 1983; Scudder & Karimabadi, ApJ, 770:26, 2013) . Indeed, using a fully kinetic model including the effect of Coulomb collisions and the expansion of the solar wind with heliocentric distance, we do observe that the heat <span class="hlt">flux</span> strength approaches the collisional value for Knudsen numbers below ~0.3, in rather good agreement with the experimental data of Bale et al (2013). However, closer inspection of the variation of the plasma parameters with heliocentric distance shows that for Knudsen numbers between 0.01-0.3 the heat <span class="hlt">flux</span> Q does NOT vary with temperature as predicted by Q_SH. We conclude that even though observations at 1 AU seem to indicate that the <span class="hlt">electron</span> heat <span class="hlt">flux</span> intensity Q approaches the collisional limit Q_SH for Knudsen below ~0.3, the latter is not a generally valid closure in the solar wind for Knudsen large that 0.01.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EPJB...90...56H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EPJB...90...56H"><span>Magnetic <span class="hlt">flux</span> and strain effects on <span class="hlt">electron</span> transport in a linear array of nanoscopic rings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hedin, Eric R.; Joe, Yong S.</p> <p>2017-03-01</p> <p><span class="hlt">Electron</span> transport through a linear array of nanoscopic rings with six quantum dot sites per ring is investigated in the presence of an external magnetic <span class="hlt">flux</span> producing an Aharonov-Bohm phase shift effect. A tight-binding model is employed to analytically calculate the transmission as a function of <span class="hlt">electron</span> energy, external <span class="hlt">flux</span>, and inter-site coupling parameters. Current vs. voltage relationships of the ring system are computed using a standard scattering theory of transport and shown to modulate between semiconductor and ohmic characteristics. System parameters are adjusted in order to study the effects of a longitudinal strain on the transmission properties of the linear multiple-ring array. Longitudinal strain is modeled with a Slater-Koster type theory and is demonstrated to affect the transmission properties primarily by narrowing the transmission bands and opening up additional bandgaps in the band structure. In addition, a universal resonant transmission condition as a function of <span class="hlt">flux</span> is extended to show that the application of strain causes the resonant transmission peaks to converge towards one-half of a <span class="hlt">flux</span> quantum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..MARA29008Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..MARA29008Z"><span>Coherent coupling of a superconducting <span class="hlt">flux</span> qubit to an <span class="hlt">electron</span> spin ensemble in diamond</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, Xiaobo; Saito, Shiro; Kemp, Alexander; Kakuyanagi, Kosuke; Karimoto, Shin-Ichi; Nakano, Hayato; Munro, William J.; Tokura, Yasuhiro; Everitt, Mark S.; Nemoto, Kae; Kasu, Makoto; Mizuochi, Norikazu; Semba, Kouichi</p> <p>2012-02-01</p> <p>We have experimentally demonstrated coherent strong coupling between a single macroscopic superconducting artificial atom (a gap tunable <span class="hlt">flux</span> qubit [1]) and an ensemble of <span class="hlt">electron</span> spins in the form of nitrogen--vacancy color centres in diamond. We have observed coherent exchange of a single quantum of energy between a <span class="hlt">flux</span> qubit and a macroscopic ensemble consisting of about 3.0*10^7 NV- centers [2]. This is the first step towards the realization of a long-lived quantum memory and hybrid devices coupling microwave and optical systems. [1] Coherent operation of a gap-tunable <span class="hlt">flux</span> qubit X. B. Zhu, A. Kemp, S. Saito, K. Semba, APPLIED PHYSICS LETTERS, Volume: 97, Issue: 10 pp. 102503 (2010) [2] Coherent coupling of a superconducting <span class="hlt">flux</span> qubit to an <span class="hlt">electron</span> spin ensemble in diamond Xiaobo Zhu, Shiro Saito, Alexander Kemp, Kosuke Kakuyanagi, Shin-ichi Karimoto, Hayato Nakano, William J. Munro, Yasuhiro Tokura, Mark S. Everitt, Kae Nemoto, Makoto Kasu, Norikazu Mizuochi, and Kouichi Semba, Nature, Volume: 478, 221-224 (2011)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1913490D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1913490D"><span>Nearly relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> and ionospheric parameters as components of space weather</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dudnik, Oleksiy; Rothkaehl, Hanna; Matyjasiak, Barbara</p> <p>2017-04-01</p> <p>We present specific features detected in spatial distributions of magnetospheric high energy <span class="hlt">electrons</span> and in ionosphere plasma <span class="hlt">electron</span> densities and temperatures during a deep minimum of 11 year's cycle of solar activity. New outcome comes as a result of joint analysis of experimental data derived from the satellite telescope of <span class="hlt">electrons</span> and protons STEP-F aboard the low, circular and highly inclined orbit CORONAS-Photon satellite, and from Demeter satellite. The highly sensitive STEP-F instrument flown in 2009 and measured sub-relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> and protons of intermediate energies by extensive-angled telescopic system of detectors at the height of 550 km covering the wide range of McIlwain L-parameters from 1 up to 20. We present peculiar characteristics of <span class="hlt">electron</span> flows in well-known Van Allen outer and inner radiation belts, inside the region of South Atlantic Anomaly and outside of mentioned zones observed during the first half of May, 2009. In spite of extremely low solar activity, and the presence of single geomagnetic substorm on May, 6-8, which was characterized by remarkably small Dst =-30 nT, substantial variations of <span class="hlt">electron</span> <span class="hlt">fluxes</span> with energies E > 180 keV came into being in all zones of enhanced charge radiation. It was clearly seen elongation of the South Atlantic Anomaly in terms of <span class="hlt">electron</span> flows up to low and near-equatorial latitudes to eastern-directed longitudes. Throughout the whole period there were recorded two radiation belts in the inner magnetosphere: well-studied at L 2.3, and additional one at L 1.6. The third radiation belt at L 1.6 had specific belt-shaped profile of particle <span class="hlt">fluxes</span>, and registered at broad range of longitudes that do not coincide with those ones related to the Anomaly location. The analyses of subrelativistic <span class="hlt">electrons</span> at the heights of upper ionosphere and inospheric plasma parameters has been analysed. From this standpoint we consider <span class="hlt">electron</span> <span class="hlt">flux</span> pulsations during various phases of geomagnetic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AIPC.1320..227V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AIPC.1320..227V"><span>Stormtime Dynamics of the Relativistic <span class="hlt">Electron</span> <span class="hlt">Flux</span> in Earth's Radiation Belts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vassiliadis, D.</p> <p>2011-01-01</p> <p>A state-vector representation is a powerful technique for describing complex plasma systems. Its framework can be adapted for classification methods which can be used to analyze the system's history and for prediction methods which can serve to forecast its future activity. A state-vector description is developed for the <span class="hlt">electron</span> <span class="hlt">flux</span> dynamics in Earth's radiation belts, based on an 11-year (1993-2003) dataset of high-cadence <span class="hlt">flux</span> measurements from a low-Earth (SAMPEX) orbit over a wide L range and at a fixed energy (2-6 MeV). A clustering algorithm is used to divide the state space into regions, or clusters of vectors, and it becomes evident that <span class="hlt">flux</span> intensifications during storms correspond to characteristic transitions in state space following geoeffective interplanetary disturbances (such as interplanetary coronal mass ejections and high-speed streams). Examples are discussed to show that the classification is valid for medium-term (several-days) and long-term (solar-cycle-phase) timescales. The state-vector representation is then used as the basis of a predictive model of the <span class="hlt">flux</span> distribution given upstream solar wind measurements. It is found that model accuracy of storm prediction is maximized if the model is tuned at a highly nonlinear regime. The relation to earlier state representations and models of the radiation belt <span class="hlt">flux</span> is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.9560G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.9560G"><span>The role of localized inductive electric fields in <span class="hlt">electron</span> injections around dipolarizing <span class="hlt">flux</span> bundles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gabrielse, Christine; Harris, Camilla; Angelopoulos, Vassilis; Artemyev, Anton; Runov, Andrei</p> <p>2016-10-01</p> <p>We study energetic <span class="hlt">electron</span> injections by using an analytical model that self-consistently describes electric and magnetic field perturbations of a transient, localized dipolarizing <span class="hlt">flux</span> bundle (DFB). This simple model reproduces most injection signatures at multiple locations simultaneously, reaffirming earlier findings that an earthward-traveling DFB can both transport and accelerate <span class="hlt">electrons</span> to suprathermal energies, and can thus be considered an important driver of short-lived ( < 10 min) injections. We find that energetic <span class="hlt">electron</span> drift paths are greatly influenced by the sharp magnetic field gradients around a localized DFB. Because a DFB is so localized (only a few RE wide across the tail), there are strong duskward magnetic field gradients on the DFB's dawn flank and strong dawnward magnetic field gradients on its dusk flank. <span class="hlt">Electrons</span> on the DFB's dawnside therefore ∇B drift farther earthward from the reconnection site, whereas <span class="hlt">electrons</span> on its duskside can potentially evacuate the inner magnetosphere by ∇B drifting tailward. This results in <span class="hlt">flux</span> decrease at the front's duskside. As a result, the source of <span class="hlt">electrons</span> observed during injection depends sensitively on the spacecraft location relative to the DFB and on the DFB's properties. We similarly find that the process of <span class="hlt">electron</span> energization depends on how the <span class="hlt">electrons</span> interact with the DFB. The initial injection signature is from <span class="hlt">electrons</span> that interact with the front and gain the majority of their energy from the increasing magnetic field (∂B/∂t), whereas populations that arrive later gain most of their energy from ∇B drifting across the flow channel and against the DFB's electric fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22408105','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22408105"><span>Fast <span class="hlt">electron</span> <span class="hlt">flux</span> driven by lower hybrid wave in the scrape-off layer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, Y. L.; Xu, G. S.; Wang, H. Q.; Wan, B. N.; Chen, R.; Wang, L.; Gan, K. F.; Yang, J. H.; Zhang, X. J.; Liu, S. C.; Li, M. H.; Ding, S.; Yan, N.; Zhang, W.; Hu, G. H.; Liu, Y. L.; Shao, L. M.; Li, J.; Chen, L.; Zhao, N.; and others</p> <p>2015-02-15</p> <p>The fast <span class="hlt">electron</span> <span class="hlt">flux</span> driven by Lower Hybrid Wave (LHW) in the scrape-off layer (SOL) in EAST is analyzed both theoretically and experimentally. The five bright belts flowing along the magnetic field lines in the SOL and hot spots at LHW guard limiters observed by charge coupled device and infrared cameras are attributed to the fast <span class="hlt">electron</span> <span class="hlt">flux</span>, which is directly measured by retarding field analyzers (RFA). The current carried by the fast <span class="hlt">electron</span> <span class="hlt">flux</span>, ranging from 400 to 6000 A/m{sup 2} and in the direction opposite to the plasma current, is scanned along the radial direction from the limiter surface to the position about 25 mm beyond the limiter. The measured fast <span class="hlt">electron</span> <span class="hlt">flux</span> is attributed to the high parallel wave refractive index n{sub ||} components of LHW. According to the antenna structure and the LHW power absorbed by plasma, a broad parallel electric field spectrum of incident wave from the antennas is estimated. The radial distribution of LHW-driven current density is analyzed in SOL based on Landau damping of the LHW. The analytical results support the RFA measurements, showing a certain level of consistency. In addition, the deposition profile of the LHW power density in SOL is also calculated utilizing this simple model. This study provides some fundamental insight into the heating and current drive effects induced by LHW in SOL, and should also help to interpret the observations and related numerical analyses of the behaviors of bright belts and hot spots induced by LHW.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..484..465K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..484..465K"><span>Modeling of possible localized <span class="hlt">electron</span> <span class="hlt">flux</span> in cosmic rays with Alpha Magnetic Spectrometer measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kwang-Hua, Chu Rainer</p> <p>2017-10-01</p> <p>Discrete quantum Boltzmann model together with the introduction of an external-field-tuned orientation parameter as well as the acoustic analog are adopted to study the possible localization of <span class="hlt">electron</span> (fermion) <span class="hlt">flux</span> in cosmic rays considering the precision measurement with the Alpha Magnetic Spectrometer (AMS) on the International Space Station (ISS). Our approximate results match qualitatively with those data measured with the AMS on the ISS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1212474-background-correction-algorithm-van-allen-probes-mageis-electron-flux-measurements','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1212474-background-correction-algorithm-van-allen-probes-mageis-electron-flux-measurements"><span>A background correction algorithm for Van Allen Probes MagEIS <span class="hlt">electron</span> <span class="hlt">flux</span> measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Claudepierre, S. G.; O'Brien, T. P.; Blake, J. B.; ...</p> <p>2015-07-14</p> <p>We describe an automated computer algorithm designed to remove background contamination from the Van Allen Probes Magnetic <span class="hlt">Electron</span> Ion Spectrometer (MagEIS) <span class="hlt">electron</span> <span class="hlt">flux</span> measurements. We provide a detailed description of the algorithm with illustrative examples from on-orbit data. We find two primary sources of background contamination in the MagEIS <span class="hlt">electron</span> data: inner zone protons and bremsstrahlung X-rays generated by energetic <span class="hlt">electrons</span> interacting with the spacecraft material. Bremsstrahlung X-rays primarily produce contamination in the lower energy MagEIS <span class="hlt">electron</span> channels (~30–500 keV) and in regions of geospace where multi-M eV <span class="hlt">electrons</span> are present. Inner zone protons produce contamination in all MagEIS energymore » channels at roughly L < 2.5. The background-corrected MagEIS <span class="hlt">electron</span> data produce a more accurate measurement of the <span class="hlt">electron</span> radiation belts, as most earlier measurements suffer from unquantifiable and uncorrectable contamination in this harsh region of the near-Earth space environment. These background-corrected data will also be useful for spacecraft engineering purposes, providing ground truth for the near-Earth <span class="hlt">electron</span> environment and informing the next generation of spacecraft design models (e.g., AE9).« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1212474','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1212474"><span>A background correction algorithm for Van Allen Probes MagEIS <span class="hlt">electron</span> <span class="hlt">flux</span> measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Claudepierre, S. G.; O'Brien, T. P.; Blake, J. B.; Fennell, J. F.; Roeder, J. L.; Clemmons, J. H.; Looper, M. D.; Mazur, J. E.; Mulligan, T. M.; Spence, H. E.; Reeves, G. D.; Friedel, R. H. W.; Henderson, M. G.; Larsen, B. A.</p> <p>2015-07-14</p> <p>We describe an automated computer algorithm designed to remove background contamination from the Van Allen Probes Magnetic <span class="hlt">Electron</span> Ion Spectrometer (MagEIS) <span class="hlt">electron</span> <span class="hlt">flux</span> measurements. We provide a detailed description of the algorithm with illustrative examples from on-orbit data. We find two primary sources of background contamination in the MagEIS <span class="hlt">electron</span> data: inner zone protons and bremsstrahlung X-rays generated by energetic <span class="hlt">electrons</span> interacting with the spacecraft material. Bremsstrahlung X-rays primarily produce contamination in the lower energy MagEIS <span class="hlt">electron</span> channels (~30–500 keV) and in regions of geospace where multi-M eV <span class="hlt">electrons</span> are present. Inner zone protons produce contamination in all MagEIS energy channels at roughly L < 2.5. The background-corrected MagEIS <span class="hlt">electron</span> data produce a more accurate measurement of the <span class="hlt">electron</span> radiation belts, as most earlier measurements suffer from unquantifiable and uncorrectable contamination in this harsh region of the near-Earth space environment. These background-corrected data will also be useful for spacecraft engineering purposes, providing ground truth for the near-Earth <span class="hlt">electron</span> environment and informing the next generation of spacecraft design models (e.g., AE9).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21067278','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21067278"><span>GeV flares observations with GLAST <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Galli, A.; Omodei, N.; Piro, L.</p> <p>2007-07-12</p> <p>Early X-ray afterglow observations show that X-ray flares are very common features in GRB light curves. X-ray flares may reflect long duration central engine activity. The delayed flare photons are expected to interact with relativistic <span class="hlt">electrons</span> by Inverse Compton giving delayed high energy counterparts that potentially will be detected by GLAST <span class="hlt">LAT</span>, which could observe GRB from 20 MeV to more than 300 GeV. The nature oh high energy spectral components from GRB detected by EGRET is still debated. Observations with GLAST <span class="hlt">LAT</span> will give useful information to constrain the origin of X-ray flares. In this work we simulate a set of possible GeV emitting flares in the context of External Shock model to study the capability of GLAST <span class="hlt">LAT</span> to detect GeV flares at different intensities and durations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ASSP...32..165J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ASSP...32..165J"><span>Degradation of Silicone Oils Exposed to Geostationary Environment Components: Ultraviolet Radiations and <span class="hlt">Electron</span> <span class="hlt">Flux</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jochem, H.; Rejsek-Riba, V.; Maerten, E.; Baceiredo, A.; Remaury, S.</p> <p></p> <p>Degradation of polydimethylsiloxane and vinyl-terminated polydimethylsiloxane oils exposed to UV radiation or 1.25 MeV <span class="hlt">electron</span> <span class="hlt">flux</span> was investigated using EPR, GC Headspace, NMR, GPC and UV-vis-NIR spectroscopy. To examine the influence of synthetic method, these two oils were prepared by ring opening polymerization using either an inorganic initiator KOH or an organic catalyst N-Heterocyclic carbene. Under UV radiation, any chemical change is observed for polydimethylsiloxane, whereas vinyl-terminated polydimethylsiloxane presents a decrease of vinyl functions and an increase of chain length. Both polydimethylsiloxane and vinyl terminated polydimethylsiloxane demonstrated a degradation of thermo-optical properties, more significant for oils synthesized with organic catalyst. By improving oil purification, the degradation of thermo-optical properties can be reduced. Effects of <span class="hlt">electron</span> <span class="hlt">flux</span> are similar for each oil, thus independently of synthetic method and end functions. <span class="hlt">Electron</span> <span class="hlt">flux</span> generates important chemical damages initiated by homolytic chain scissions. Radical recombination produces gases (methane and ethane), new functions (Si-H) and bonds across silicone chains leading to a solid state material. Crosslinking of chains occurs by formation of R-Si-(O)3 and Si-CH2-Si groups. Silyl radicals are trapped in the polymer network and can be detected even 1 week after the end of irradiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSM41A2465O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSM41A2465O"><span>Statistical Observations and Predictions of Time Changes in <span class="hlt">Electron</span> <span class="hlt">Flux</span> at Geosynchronous Orbit</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olson, D. K.; Larsen, B.; Friedel, R. H.; Geoffrey, R.</p> <p>2015-12-01</p> <p>A statistical survey of time changes in particle <span class="hlt">flux</span> values (df/dt) at geosynchronous orbit reveals trends that are instructive to predictive magnetosphere models. A single spacecraft can provide short time scale df/dt measurements, while multiple spacecraft can provide values over periods comparable to the spacecraft separation. Using data from multiple LANL-GEO spacecraft provides a unique view of temporal and spatial variations that allow us to gauge time and length scales for changing particle <span class="hlt">fluxes</span> at GEO. These scales provide a base ability to predict the plasma environment conditions for spacecraft crossing GEO. Probability distribution functions based on <span class="hlt">electron</span> df/dt values are used to predict the <span class="hlt">electron</span> <span class="hlt">flux</span> at a given magnetic local time at GEO based on prior measurements. The predictions, when compared to new data taken in the same region, provide some measure of how the <span class="hlt">electron</span> plasma environment at GEO has changed in the interim period. These predictions are compared to data from the Van Allen Probes as their orbits cross GEO to verify the validity of this technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880042165&hterms=ISEE-3&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DISEE-3','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880042165&hterms=ISEE-3&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DISEE-3"><span>Interplanetary magnetic field orientations associated with bidirectional <span class="hlt">electron</span> heat <span class="hlt">fluxes</span> detected at ISEE 3</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stansberry, J. A.; Gosling, J. T.; Thomsen, M. F.; Bame, S. J.; Smith, E. J.</p> <p>1988-01-01</p> <p>A statistical survey of interplanetary magnetic field orientations associated with bidirectional <span class="hlt">electron</span> heat <span class="hlt">fluxes</span> observed at ISEE 3 in orbit about the Sunward Lagrange point indicates that magnetic connection of the spacecraft to the earth's shock was frequently the source of the bidirectionality. When the interplanetary magnetic field was oriented within 5 deg of the earth-spacecraft line, backstreaming <span class="hlt">electrons</span> from the bow shock were clearly observed approximately 18 percent of the time, and connections apparently occurred for angles as large as about 30-35 deg.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCo...712633A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCo...712633A"><span><span class="hlt">Electron-flux</span> infrared response to varying π-bond topology in charged aromatic monomers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Álvaro Galué, Héctor; Oomens, Jos; Buma, Wybren Jan; Redlich, Britta</p> <p>2016-08-01</p> <p>The interaction of delocalized π-<span class="hlt">electrons</span> with molecular vibrations is key to charge transport processes in π-conjugated organic materials based on aromatic monomers. Yet the role that specific aromatic motifs play on charge transfer is poorly understood. Here we show that the molecular edge topology in charged catacondensed aromatic hydrocarbons influences the Herzberg-Teller coupling of π-<span class="hlt">electrons</span> with molecular vibrations. To this end, we probe the radical cations of picene and pentacene with benchmark armchair- and zigzag-edges using infrared multiple-photon dissociation action spectroscopy and interpret the recorded spectra via quantum-chemical calculations. We demonstrate that infrared bands preserve information on the dipolar π-<span class="hlt">electron-flux</span> mode enhancement, which is governed by the dynamical evolution of vibronically mixed and correlated one-<span class="hlt">electron</span> configuration states. Our results reveal that in picene a stronger charge π-<span class="hlt">flux</span> is generated than in pentacene, which could justify the differences of <span class="hlt">electronic</span> properties of armchair- versus zigzag-type families of technologically relevant organic molecules.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...848L...3F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...848L...3F"><span>Origin of the Differential <span class="hlt">Fluxes</span> of Low-energy <span class="hlt">Electrons</span> in the Inner Heliosheath</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fahr, H. J.; Krimigis, S. M.; Fichtner, H.; Scherer, K.; Sylla, A.; Ferreira, S. E. S.; Potgieter, M. S.</p> <p>2017-10-01</p> <p>The study addresses the question of the origin of low-energy <span class="hlt">electrons</span> measured by Voyager 1 in the multi-keV range in the inner heliosheath. It intends to demonstrate that the observed keV-<span class="hlt">fluxes</span> of <span class="hlt">electrons</span> are consistent with their transmission through the termination shock under the influence of the associated electrostatic field. A power-law representation of the <span class="hlt">electron</span> velocity distribution just downstream of the solar wind termination shock is motivated and formulated in terms of a so-called κ-distribution function. From this initial function spectral <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the range 40–70 keV are derived and compared to the data. It is shown that with κ-values between 7 and 8 the data can be satisfactorily explained. Given these comparatively high κ-values, it is concluded that the <span class="hlt">electron</span> distribution just downstream of the termination shock relaxes toward but does not reach a Maxwellian shape in the inner heliosheath.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5013661','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5013661"><span><span class="hlt">Electron-flux</span> infrared response to varying π-bond topology in charged aromatic monomers</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Álvaro Galué, Héctor; Oomens, Jos; Buma, Wybren Jan; Redlich, Britta</p> <p>2016-01-01</p> <p>The interaction of delocalized π-<span class="hlt">electrons</span> with molecular vibrations is key to charge transport processes in π-conjugated organic materials based on aromatic monomers. Yet the role that specific aromatic motifs play on charge transfer is poorly understood. Here we show that the molecular edge topology in charged catacondensed aromatic hydrocarbons influences the Herzberg-Teller coupling of π-<span class="hlt">electrons</span> with molecular vibrations. To this end, we probe the radical cations of picene and pentacene with benchmark armchair- and zigzag-edges using infrared multiple-photon dissociation action spectroscopy and interpret the recorded spectra via quantum-chemical calculations. We demonstrate that infrared bands preserve information on the dipolar π-<span class="hlt">electron-flux</span> mode enhancement, which is governed by the dynamical evolution of vibronically mixed and correlated one-<span class="hlt">electron</span> configuration states. Our results reveal that in picene a stronger charge π-<span class="hlt">flux</span> is generated than in pentacene, which could justify the differences of <span class="hlt">electronic</span> properties of armchair- versus zigzag-type families of technologically relevant organic molecules. PMID:27577323</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1818101T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1818101T"><span>Variation of energetic <span class="hlt">electron</span> <span class="hlt">flux</span> in Earth's radiation belts based on Van Allen Probes observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, Rongxin; Zhong, Zhihong; Yu, Deyin</p> <p>2016-04-01</p> <p>The Earth's radiation belts have been an important research topic of solar-terrestrial physics from 1958. In 2012, Van Allen Probes (VAP) were launched into near-equatorial orbit and provide very good in-situ observations of energetic particles in inner magnetosphere. Since magnetospheric substorm can cause the severe disturbance of the Earth's megnetospheric environment, here we focus on the characteristics of energetic <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the radiation belts during substorm time and non-storm time. Energetic <span class="hlt">electron</span> data observed by the Magnetic <span class="hlt">Electron</span> Ion Spectrometer (MagEIS) and Energetic Particle Composition and Thermal Plasma Suite (ECT) of VAP during 2012 to 2014 are carefully analyzed. We select portions of energetic <span class="hlt">electron</span> data from substorm onset phase, growth phase, recovery phase, and quiet time, and make a comparisons with theoretical computations. We find that the <span class="hlt">electron</span> differential <span class="hlt">fluxes</span> present E-1 shape at lower energies (<1MeV), and have a sharp transition with steeper slopes at high energies for large L-shells, which are in coincidence with Mauk's model [Mauk et al., 2010].</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820028335&hterms=energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D90%26Ntt%3Denergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820028335&hterms=energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D90%26Ntt%3Denergy"><span>A satellite investigation of energy <span class="hlt">flux</span> and inferred potential drop in auroral <span class="hlt">electron</span> energy spectra</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Menietti, J. D.; Burch, J. L.</p> <p>1981-01-01</p> <p>The relationship between auroral <span class="hlt">electron</span> energy <span class="hlt">flux</span> and the inferred accelerating potential drop for accelerated Maxwellian distributions is investigated on the basis of Atmospheric Explorer D spectral measurements. An analytical approximation for the total downward energy <span class="hlt">flux</span> carried by an isotropic Maxwellian <span class="hlt">electron</span> population accelerated by a field-aligned electrostatic potential drop is derived which is valid for values of the <span class="hlt">electron</span> energy/characteristic accelerated Maxwellian distribution energy which are less than the difference between the ratio of the magnetic field strengths at the altitude of observation and the altitude of potential drop, and unity. Data from the Low Energy <span class="hlt">Electron</span> Experiment on board AE D obtained on both the dayside and the nightside during periods of significant inverted-V type <span class="hlt">electron</span> precipitation shows that the 455 energy spectra considered, 160 of them, obtained between 60 and 85 deg invariant latitude, could be fit to accelerated Maxwellian distributions. The 160 Maxwellian spectra are then shown to be in agreement with the predictions of the accelerated Maxwellian model. Finally, analysis of individual spectra suggests that the altitude of the inferred potential drop is at a maximum near the center of the inverted-V structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21293541','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21293541"><span>Solar System Gamma Ray observations using Fermi-<span class="hlt">LAT</span> detector</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Giglietto, N.</p> <p>2009-04-08</p> <p>The Fermi Gamma-ray Space Telescope, launched in June 2008, is an international space mission dedicated to the study of the high-energy gamma rays from the Universe. The main instrument aboard Fermi is the Large Area Telescope (<span class="hlt">LAT</span>), a pair conversion telescope equipped with the state-of-the art in gamma-ray detectors technology, and operating at energies >30 MeV. During first two months of data taking, Fermi has detected high-energy gamma rays from the quiet Sun and the Moon. This emission is produced by interactions of cosmic rays; by nucleons with the solar and lunar surface, and <span class="hlt">electrons</span> with solar photons in the heliosphere. While the Moon was detected by EGRET on CGRO with low statistics, Fermi provides high-sensitivity measurements on a daily basis allowing both short- and long-term variability to be studied. Since Galactic cosmic rays are at their maximum <span class="hlt">flux</span> at solar minimum we expect that the quiescent solar and lunar emission to be a maximum during the period covered by this report. Fermi is the only mission capable of monitoring the Sun at energies above several hundred MeV over the full 24th solar cycle. We present first analysis showing images of Moon and the quiet emission of the solar disk, giving a description of the analysis tools used.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016RScI...87k4101N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016RScI...87k4101N"><span>Liquid-phase catalytic reactor combined with measurement of hot <span class="hlt">electron</span> <span class="hlt">flux</span> and chemiluminescence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nedrygailov, Ievgen I.; Lee, Changhwan; Moon, Song Yi; Lee, Hyosun; Park, Jeong Young</p> <p>2016-11-01</p> <p>Understanding the role of <span class="hlt">electronically</span> nonadiabatic interactions during chemical reactions on metal surfaces in liquid media is of great importance for a variety of applications including catalysis, electrochemistry, and environmental science. Here, we report the design of an experimental apparatus for detection of the highly excited (hot) <span class="hlt">electrons</span> created as a result of nonadiabatic energy transfer during the catalytic decomposition of hydrogen peroxide on thin-film metal-semiconductor nanodiodes. The apparatus enables the measurement of hot <span class="hlt">electron</span> flows and related phenomena (e.g., surface chemiluminescence) as well as the corresponding reaction rates at different temperatures. The products of the chemical reaction can be characterized in the gaseous phase by means of gas chromatography. The combined measurement of hot <span class="hlt">electron</span> <span class="hlt">flux</span>, catalytic activity, and light emission can lead to a fundamental understanding of the elementary processes occurring during the heterogeneous catalytic reaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920059359&hterms=dropout&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddropout','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920059359&hterms=dropout&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddropout"><span>Interplanetary magnetic field connection to the sun during <span class="hlt">electron</span> heat <span class="hlt">flux</span> dropouts in the solar wind</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lin, R. P.; Kahler, S. W.</p> <p>1992-01-01</p> <p>The paper discusses observations of 2- to 8.5-keV <span class="hlt">electrons</span>, made by measurements aboard the ISEE 3 spacecraft during the periods of heat <span class="hlt">flux</span> decreases (HFDs) reported by McComas et al. (1989). In at least eight of the total of 25 HFDs observed, strong streaming of <span class="hlt">electrons</span> that were equal to or greater than 2 keV outward from the sun was recorded. In one HFD, an impulsive solar <span class="hlt">electron</span> event was observed with an associated type III radio burst, which could be tracked from the sun to about 1 AU. It is concluded that, in many HFDs, the interplanetary field is still connected to the sun and that some energy-dependent process may produce HFDs without significantly perturbing <span class="hlt">electrons</span> of higher energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27910578','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27910578"><span>Liquid-phase catalytic reactor combined with measurement of hot <span class="hlt">electron</span> <span class="hlt">flux</span> and chemiluminescence.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nedrygailov, Ievgen I; Lee, Changhwan; Moon, Song Yi; Lee, Hyosun; Park, Jeong Young</p> <p>2016-11-01</p> <p>Understanding the role of <span class="hlt">electronically</span> nonadiabatic interactions during chemical reactions on metal surfaces in liquid media is of great importance for a variety of applications including catalysis, electrochemistry, and environmental science. Here, we report the design of an experimental apparatus for detection of the highly excited (hot) <span class="hlt">electrons</span> created as a result of nonadiabatic energy transfer during the catalytic decomposition of hydrogen peroxide on thin-film metal-semiconductor nanodiodes. The apparatus enables the measurement of hot <span class="hlt">electron</span> flows and related phenomena (e.g., surface chemiluminescence) as well as the corresponding reaction rates at different temperatures. The products of the chemical reaction can be characterized in the gaseous phase by means of gas chromatography. The combined measurement of hot <span class="hlt">electron</span> <span class="hlt">flux</span>, catalytic activity, and light emission can lead to a fundamental understanding of the elementary processes occurring during the heterogeneous catalytic reaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920059359&hterms=college+dropouts&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcollege%2Bdropouts','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920059359&hterms=college+dropouts&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcollege%2Bdropouts"><span>Interplanetary magnetic field connection to the sun during <span class="hlt">electron</span> heat <span class="hlt">flux</span> dropouts in the solar wind</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lin, R. P.; Kahler, S. W.</p> <p>1992-01-01</p> <p>The paper discusses observations of 2- to 8.5-keV <span class="hlt">electrons</span>, made by measurements aboard the ISEE 3 spacecraft during the periods of heat <span class="hlt">flux</span> decreases (HFDs) reported by McComas et al. (1989). In at least eight of the total of 25 HFDs observed, strong streaming of <span class="hlt">electrons</span> that were equal to or greater than 2 keV outward from the sun was recorded. In one HFD, an impulsive solar <span class="hlt">electron</span> event was observed with an associated type III radio burst, which could be tracked from the sun to about 1 AU. It is concluded that, in many HFDs, the interplanetary field is still connected to the sun and that some energy-dependent process may produce HFDs without significantly perturbing <span class="hlt">electrons</span> of higher energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21476101','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21476101"><span>High energy <span class="hlt">electron</span> <span class="hlt">fluxes</span> in dc-augmented capacitively coupled plasmas I. Fundamental characteristics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang Mingmei; Kushner, Mark J.</p> <p>2010-01-15</p> <p>Power deposition from <span class="hlt">electrons</span> in capacitively coupled plasmas (CCPs) has components from stochastic heating, Joule heating, and from the acceleration of secondary <span class="hlt">electrons</span> through sheaths produced by ion, <span class="hlt">electron</span>, or photon bombardment of electrodes. The sheath accelerated <span class="hlt">electrons</span> can produce high energy beams which, in addition to producing excitation and ionization in the gas can penetrate through the plasma and be incident on the opposite electrode. In the use of CCPs for microelectronics fabrication, there may be an advantage to having these high energy <span class="hlt">electrons</span> interact with the wafer. To control the energy and increase the <span class="hlt">flux</span> of the high energy <span class="hlt">electrons</span>, a dc bias can be externally imposed on the electrode opposite the wafer, thereby producing a dc-augmented CCP (dc-CCP). In this paper, the characteristics of dc-CCPs will be discussed using results from a computational study. We found that for a given rf bias power, beams of high energy <span class="hlt">electrons</span> having a narrow angular spread (<1 deg. ) can be produced incident on the wafer. The maximum energy in the high energy <span class="hlt">electron</span> <span class="hlt">flux</span> scales as {epsilon}{sub max}=-V{sub dc}+V{sub rf}+V{sub rf0}, for a voltage on the dc electrode of V{sub dc}, rf voltage of V{sub rf}, and dc bias on the rf electrode of V{sub rf0}. The dc current from the biased electrode must return to ground through surfaces other than the rf electrode and so seeks out a ground plane, typically the side walls. If the side wall is coated with a poorly conducting polymer, the surface will charge to drive the dc current through.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9428E..0OR','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9428E..0OR"><span><span class="hlt">Electron</span> energy distribution control by fiat: breaking from the conventional <span class="hlt">flux</span> ratio scaling rules in etch</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ranjan, Alok; Wang, Mingmei; Sherpa, Sonam; Ventzek, Peter</p> <p>2015-03-01</p> <p>With shrinking critical dimensions, minimizing each of aspect ratio dependent etching (ARDE), bowing, undercut, selectivity, and within die uniformly across a wafer is met by trading off one requirement against another. The problem of trade-offs is especially critical. At the root of the problem is that roles radical <span class="hlt">flux</span>, ion <span class="hlt">flux</span> and ion energy play may be both good and bad. Increasing one parameter helps meeting one requirement but hinders meeting the other. Managing process by managing <span class="hlt">flux</span> ratios and ion energy alone with conventional sources is not adequate because surface chemistry is uncontrollable. At the root of lack of control is that the <span class="hlt">electron</span> energy distribution function (eedf) has not been controlled. Fortunately the high density surface wave sources control the eedf by fiat. High density surface wave sources are characterized by distinct plasma regions: an active plasma generation region with high <span class="hlt">electron</span> temperature (Te) and an ionization free but chemistry rich diffusive region (low Te region). Pressure aids is segregating the regions by proving a means for momentum relaxation between the source and downstream region. "Spatial pulsing" allows access to plasma chemistry with reasonably high ion <span class="hlt">flux</span>, from the active plasma generation region, just above the wafer. Low plasma potential enables precise passivation of surfaces which is critical for atomic layer etch (ALE) or high precision etch where the roles of plasma species can be limited to their purposed roles. High precision etch need not be at the cost of speed and manufacturability. Large ion <span class="hlt">flux</span> at precisely controlled ion energy with RLSATM realizes fast desorption steps for ALE without compromising process throughput and precision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSM22A..08G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSM22A..08G"><span>The Role of Localized Inductive Electric Fields in <span class="hlt">Electron</span> Injections Around Dipolarizing <span class="hlt">Flux</span> Bundles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gabrielse, C.; Harris, C.; Angelopoulos, V.; Runov, A.</p> <p>2015-12-01</p> <p>We study energetic <span class="hlt">electron</span> injections using an analytical model that describes self-consistent electric and magnetic field perturbations of a transient, localized dipolarizing <span class="hlt">flux</span> bundle (DFB). This simple model can reproduce most injection signatures at multiple locations simultaneously, reaffirming earlier findings that an earthward-traveling DFB can both transport and accelerate <span class="hlt">electrons</span> to suprathermal energies, and can thus be considered as the primary driver of short-lived (~<10 min) injections. We find that energetic <span class="hlt">electron</span> drift paths are greatly influenced by the sharp magnetic field gradients around the localized DFB. If the gradients are weak the energetic <span class="hlt">electrons</span> initiating at reconnection will drift out of the flow channel such that the observed injection is comprised mostly of plasma sheet <span class="hlt">electrons</span>. However, if the duskward magnetic field gradients on the DFB's dawn flank are strong they can cause <span class="hlt">electrons</span> to drift further earthward from the reconnection site than due to E x B alone. Similarly, strong dawnward magnetic field gradients on the DFB's dusk flank can extract energetic <span class="hlt">electrons</span> from the inner magnetosphere out to the plasma sheet, where they can either be recirculated earthward or remain at higher L-shells. Therefore, the source of <span class="hlt">electrons</span> observed during injection depends sensitively on the spacecraft location relative to the DFB and on the DFB's properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1183079','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1183079"><span>Thermal <span class="hlt">flux</span> limited <span class="hlt">electron</span> Kapitza conductance in copper-niobium multilayers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cheaito, Ramez; Hattar, Khalid Mikhiel; Gaskins, John T.; Yadav, Ajay K.; Duda, John C.; Beechem, III, Thomas Edwin; Ihlefeld, Jon; Piekos, Edward S.; Baldwin, Jon K.; Misra, Amit; Hopkins, Patrick E.</p> <p>2015-03-05</p> <p>The interplay between the contributions of <span class="hlt">electron</span> thermal <span class="hlt">flux</span> and interface scattering to the Kapitza conductance across metal-metal interfaces through measurements of thermal conductivity of copper-niobium multilayers was studied. Thermal conductivities of copper-niobium multilayer films of period thicknesses ranging from 5.4 to 96.2 nm and sample thicknesses ranging from 962 to 2677 nm are measured by time-domain thermoreflectance over a range of temperatures from 78 to 500 K. The Kapitza conductances between the Cu and Nb interfaces in multilayer films are determined from the thermal conductivities using a series resistor model and are in good agreement with the <span class="hlt">electron</span> diffuse mismatch model. The results for the thermal boundary conductance between Cu and Nb are compared to literature values for the thermal boundary conductance across Al-Cu and Pd-Ir interfaces, and demonstrate that the interface conductance in metallic systems is dictated by the temperature derivative of the <span class="hlt">electron</span> energy <span class="hlt">flux</span> in the metallic layers, rather than <span class="hlt">electron</span> mean free path or scattering processes at the interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1183079-thermal-flux-limited-electron-kapitza-conductance-copper-niobium-multilayers','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1183079-thermal-flux-limited-electron-kapitza-conductance-copper-niobium-multilayers"><span>Thermal <span class="hlt">flux</span> limited <span class="hlt">electron</span> Kapitza conductance in copper-niobium multilayers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Cheaito, Ramez; Hattar, Khalid Mikhiel; Gaskins, John T.; ...</p> <p>2015-03-05</p> <p>The interplay between the contributions of <span class="hlt">electron</span> thermal <span class="hlt">flux</span> and interface scattering to the Kapitza conductance across metal-metal interfaces through measurements of thermal conductivity of copper-niobium multilayers was studied. Thermal conductivities of copper-niobium multilayer films of period thicknesses ranging from 5.4 to 96.2 nm and sample thicknesses ranging from 962 to 2677 nm are measured by time-domain thermoreflectance over a range of temperatures from 78 to 500 K. The Kapitza conductances between the Cu and Nb interfaces in multilayer films are determined from the thermal conductivities using a series resistor model and are in good agreement with the <span class="hlt">electron</span> diffusemore » mismatch model. The results for the thermal boundary conductance between Cu and Nb are compared to literature values for the thermal boundary conductance across Al-Cu and Pd-Ir interfaces, and demonstrate that the interface conductance in metallic systems is dictated by the temperature derivative of the <span class="hlt">electron</span> energy <span class="hlt">flux</span> in the metallic layers, rather than <span class="hlt">electron</span> mean free path or scattering processes at the interface.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JPhCS.409a2223A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JPhCS.409a2223A"><span>New low threshold detectors for measuring <span class="hlt">electron</span> and gamma ray <span class="hlt">fluxes</span> from thunderclouds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arakelyan, Karen; Avakyan, Karen; Chilingarian, Ashot; Daryan, Ara; Melkumyan, Laura; Pokhsraryan, David; Sargsyan, David</p> <p>2013-02-01</p> <p>Strong electric fields inside thunderclouds give rise to enhanced <span class="hlt">fluxes</span> of high-energy <span class="hlt">electrons</span> and, consequently, gamma rays and neutrons. During thunderstorms at mountain Aragats, hundreds of Thunderstorm Ground Enhancements (TGEs) comprising millions of energetic <span class="hlt">electrons</span> and gamma rays, as well as neutrons, were detected at Aragats Space Environmental Center (ASEC) on 3200 m altitude. The energy spectra of the <span class="hlt">electrons</span> have an exponential shape and extend in energy range 2- 30 MeV. Recovered energy spectra of the gamma rays is also exponential in energy range 2-10 MeV, then turns to power law and is extending up to 100 MeV. It is of upmost importance to research energy spectra of TGE <span class="hlt">electrons</span> and gamma rays from the lowest possible energies to clarify the shape of energy spectra and huge multiplication of the avalanche particles. The particle detectors operated at ASEC was designed for the registration of solar modulation effects and the lowering energy threshold was not of first importance. Thus, particle detectors have energy threshold of 7-10 MeV. The new generation of ASEC detectors comprises from 1 and 3 cm thick molded plastic scintillators arranged in stacks (3cm and 1cm STAND detectors) and in cubical structures surrounded thick scintillators and NaI crystals for purification of detected neutral <span class="hlt">flux</span> (Cube 1 cm and Cube 3 cm detectors). In presented paper we describe new detectors and analyze their operational characteristics, as well as provide examples of TGE detection with new techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22412772','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22412772"><span>Thermal <span class="hlt">flux</span> limited <span class="hlt">electron</span> Kapitza conductance in copper-niobium multilayers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cheaito, Ramez; Gaskins, John T.; Duda, John C.; Hopkins, Patrick E.; Hattar, Khalid; Beechem, Thomas E.; Ihlefeld, Jon F.; Piekos, Edward S.; Yadav, Ajay K.; Baldwin, Jon K.; Misra, Amit</p> <p>2015-03-02</p> <p>We study the interplay between the contributions of <span class="hlt">electron</span> thermal <span class="hlt">flux</span> and interface scattering to the Kapitza conductance across metal-metal interfaces through measurements of thermal conductivity of copper-niobium multilayers. Thermal conductivities of copper-niobium multilayer films of period thicknesses ranging from 5.4 to 96.2 nm and sample thicknesses ranging from 962 to 2677 nm are measured by time-domain thermoreflectance over a range of temperatures from 78 to 500 K. The Kapitza conductances between the Cu and Nb interfaces in multilayer films are determined from the thermal conductivities using a series resistor model and are in good agreement with the <span class="hlt">electron</span> diffuse mismatch model. Our results for the thermal boundary conductance between Cu and Nb are compared to literature values for the thermal boundary conductance across Al-Cu and Pd-Ir interfaces, and demonstrate that the interface conductance in metallic systems is dictated by the temperature derivative of the <span class="hlt">electron</span> energy <span class="hlt">flux</span> in the metallic layers, rather than <span class="hlt">electron</span> mean free path or scattering processes at the interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AAS...20915310C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AAS...20915310C"><span>The GLAST <span class="hlt">LAT</span> Instrument Science Operations Center</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cameron, Robert A.; LAT ISOC, GLAST</p> <p>2006-12-01</p> <p>The Gamma-ray Large Area Space Telescope (GLAST) is scheduled for launch in late 2007. The major science instrument on GLAST is the Large Area Telescope (<span class="hlt">LAT</span>). Operations support and science data processing for the <span class="hlt">LAT</span> instrument on GLAST will be performed by the <span class="hlt">LAT</span> Instrument Science Operations Center (ISOC) at the Stanford Linear Accelerator Center (SLAC). The ISOC supports GLAST mission operations in cooperation with other GLAST mission ground system elements and supports the science research activities of the <span class="hlt">LAT</span> collaboration. The ISOC will be responsible for monitoring the health and safety of the <span class="hlt">LAT</span>, preparing command loads for the <span class="hlt">LAT</span>, maintaining and updating embedded flight software which controls the <span class="hlt">LAT</span> detector and data acquisition flight hardware, maintaining the operating configration of the <span class="hlt">LAT</span> and its calibration, and applying event reconstruction processing to downlinked <span class="hlt">LAT</span> data to recover information about detected gamma-ray photons. The SLAC computer farm will be used to process the large volume of <span class="hlt">LAT</span> event data and generate science products to be made available to the <span class="hlt">LAT</span> collaboration through the ISOC and to the broader scientific community through the GLAST Science Support Center at GSFC. Science operations in the ISOC will optimize the performance of the <span class="hlt">LAT</span> and oversee automated science processing of <span class="hlt">LAT</span> data to detect and monitor transient gamma-ray sources. We describe the use of collaboration-wide data challenges and service challenges to test and exercise <span class="hlt">LAT</span> data processing and science operations before launch. This work is supported by Stanford University and the Stanford Linear Accelerator Center (SLAC) under DoE contract number DE-AC03-76SFO0515. Non-US sources of funding also support the efforts of GLAST <span class="hlt">LAT</span> collaborators in France, Italy, Japan, and Sweden.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...833...87C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...833...87C"><span>Radio Diagnostics of <span class="hlt">Electron</span> Acceleration Sites During the Eruption of a <span class="hlt">Flux</span> Rope in the Solar Corona</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carley, Eoin P.; Vilmer, Nicole; Gallagher, Peter T.</p> <p>2016-12-01</p> <p><span class="hlt">Electron</span> acceleration in the solar corona is often associated with flares and the eruption of twisted magnetic structures known as <span class="hlt">flux</span> ropes. However, the locations and mechanisms of such particle acceleration during the flare and eruption are still subject to much investigation. Observing the exact sites of particle acceleration can help confirm how the flare and eruption are initiated and how they evolve. Here we use the Atmospheric Imaging Assembly to analyze a flare and erupting <span class="hlt">flux</span> rope on 2014 April 18, while observations from the Nançay Radio Astronomy Facility allow us to diagnose the sites of <span class="hlt">electron</span> acceleration during the eruption. Our analysis shows evidence of a pre-formed <span class="hlt">flux</span> rope that slowly rises and becomes destabilized at the time of a C-class flare, plasma jet, and the escape of ≳75 keV <span class="hlt">electrons</span> from the rope center into the corona. As the eruption proceeds, continued acceleration of <span class="hlt">electrons</span> with energies of ˜5 keV occurs above the <span class="hlt">flux</span> rope for a period over 5 minutes. At the flare peak, one site of <span class="hlt">electron</span> acceleration is located close to the flare site, while another is driven by the erupting <span class="hlt">flux</span> rope into the corona at speeds of up to 400 km s-1. Energetic <span class="hlt">electrons</span> then fill the erupting volume, eventually allowing the <span class="hlt">flux</span> rope legs to be clearly imaged from radio sources at 150-445 MHz. Following the analysis of Joshi et al. (2015), we conclude that the sites of energetic <span class="hlt">electrons</span> are consistent with <span class="hlt">flux</span> rope eruption via a tether cutting or <span class="hlt">flux</span> cancellation scenario inside a magnetic fan-spine structure. In total, our radio observations allow us to better understand the evolution of a <span class="hlt">flux</span> rope eruption and its associated <span class="hlt">electron</span> acceleration sites, from eruption initiation to propagation into the corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120014265','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120014265"><span>Fermi <span class="hlt">LAT</span> Observations of the Crab Nebula During the Exceptional April 2011 Outburst</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hays, Elizabeth</p> <p>2012-01-01</p> <p>The Crab Nebula, formerly thought to be steady in gamma rays, shows unexpected and occasionally dramatic variability in high-energy gamma rays. The Large Area Telescope (<span class="hlt">LAT</span>) on Fermi recorded several strong outbursts, including dedicated pointed observations of the brightest yet seen, a spectacular flare in April 2011. These observations provide a particularly detailed look at the temporal and spectral characteristics of the nebula during the flare. The <span class="hlt">LAT</span> data show an additional component in the spectral energy distribution that peaks at a maximum of $375\\pm26\\mathrm{MeV}$. In the probable scenario that this component is synchrotron emission, the <span class="hlt">electrons</span> are accelerated to extreme energies that are difficult to reconcile with the very rapid change in <span class="hlt">flux</span> and the expectation for acceleration processes and conditions occurring within the pulsar wind nebula. The physical location and mechanism driving the flares remains undetermined despite observations across the spectrum made by a variety of instruments including the Hubble Space Telescope, the Chandra X-ray Observatory, and the Very Large Array. I will present timing and spectral studies of the high-energy gamma-ray data, discuss implications for the origin of the flares, and highlight preparations for the next major flare.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMSM31C..07B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMSM31C..07B"><span>Ion Outflow in the Dayside Cusp Ionosphere and its Dependence on Soft <span class="hlt">Electron</span> Energy <span class="hlt">Flux</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burchill, J. K.; Knudsen, D. J.; Clemmons, J. H.; Oksavik, K.; Pfaff, R. F.; Steigies, C. T.; Yau, A. W.; Yeoman, T. K.</p> <p>2009-12-01</p> <p>We investigate the origin of low energy (Ek<10 eV) ion upflows in Earth's low-altitude dayside cusp region. The Cusp-2002 sounding rocket flew from Ny Ålesund, Svalbard, on 14 December 2002, carrying plasma and field instrumentation to an altitude of 768 km. The Suprathermal Ion Imager, a two-dimensional energy/arrival-angle spectrograph, observed large (>500 m/s) O+ upflows within the cusp at altitudes between 640 km and 768 km. We report a significant association between ion upflow and precipitating magnetosheath <span class="hlt">electron</span> energy <span class="hlt">flux</span> in this altitude range, but no causal links between upflow and either wave power or the magnitude of the dc electric field. The correspondence between upflow and logarithm of the <span class="hlt">electron</span> energy <span class="hlt">flux</span> suggests a mechanism whereby ions are accelerated locally by ambipolar electric fields that are driven by the soft <span class="hlt">electrons</span>. Significant ion upflows are not observed for <span class="hlt">electron</span> energy <span class="hlt">fluxes</span> below ˜1010 eV cm-2s-1, which suggests that any ambipolar fields present above 640 km must be in equilibrium with gravity and pressure gradients under this condition. The lack of correspondence between │E│ and upflow on the one hand, and wave power and upflow on the other, does not rule out these processes, but implies that, if operating, they are not local to the measurement region. We observe narrow regions of large downflow that imply either a re-balancing of the ionosphere toward a low-Te equilibrium during which gravity dominates the pressure gradients, or convection of the upflowing ions away from the precipitation region, outside of which the ions must fall back into equilibrium at lower altitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110005635','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110005635"><span>New Results on High Energy Cosmic Ray <span class="hlt">Electrons</span> Observed with Fermi <span class="hlt">LAT</span> and Their Implications on the Origin of Cosmic Rays</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Moiseev, Alexander</p> <p>2010-01-01</p> <p>The Large Area Telescope on-board the Fermi Gamma-Ray Space Telescope has collected more than 10 million cosmic ray <span class="hlt">electrons</span> with energy above 7 GeV since its science operation on orbit. High energy <span class="hlt">electrons</span> rapidly lose their energy by synchrotron radiation on Galactic magnetic fields and by inverse Compton scattering on the interstellar radiation field. The typical distance over which a 1 TeV <span class="hlt">electron</span> loses half its total energy is estimated to be 300-400 pc.This makes them a unique tool for probing nearby Galactic space. Observed spectrum has a harder spectral index than was previously reported and suggests the presence of nearby sources of high energy <span class="hlt">electrons</span>. One of viable candidates are nearby pulsars, possibly some of recently discovered by Fermi. At the same time the dark matter origin of such sources cannot be ruled out. I will also report our current upper limits on cosmic ray <span class="hlt">electrons</span> anisotropy which helps to set constraints on their local sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMAE31A3396A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMAE31A3396A"><span>In-Situ observation of energetic <span class="hlt">electron</span> <span class="hlt">fluxes</span> inside thunderclouds using Balloon-borne instruments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arabshahi, S.; Vodopiyanov, I. B.; Dwyer, J. R.; Sadighi, S.; Cramer, E. S.; Kosar, B.; Rassoul, H.</p> <p>2014-12-01</p> <p>In this presentation we will report on our first observations of energetic <span class="hlt">electron</span> <span class="hlt">flux</span> from inside thunderclouds. Energetic <span class="hlt">electrons</span> can produce high-energy radiation. High-energy radiation is routinely produced by thunderclouds and lightning. This radiation is in the form of x-rays and gamma-rays with timescales ranging from sub-microsecond (x-rays associated with lightning leaders), to sub-millisecond (Terrestrial Gamma ray Flashes), to minute long glows (Gamma-ray Glows from thunderclouds seen on the ground and in or near the cloud by aircrafts and balloons). It is generally accepted that these emissions originate from bremsstrahlung interactions of relativistic runaway <span class="hlt">electrons</span> with air, which can be accelerated in the thundercloud/lightning electric fields and gain up to multi-MeV energies. However, the exact physical details of the mechanism that produces these runaway <span class="hlt">electrons</span> are still unknown. Our balloon-borne campaign at Florida Tech is intended to directly measure the <span class="hlt">flux</span> of energetic <span class="hlt">electrons</span> inside thunderclouds. Each balloon carries two Geiger counters to record the energetic particles. Geiger counters are well suited for directly measuring energetic <span class="hlt">electrons</span> and positrons and have the advantage of being lightweight and dependable. Data from our payloads are saved onboard and also get transmitted in real time to our ground station at a transmission rate of 115.2 kb/s. This would provide us a high resolution radiation profile over a relatively large distance. This work was supported in part by the NASA grant NNX12A002H and by DARPA grant HR0011-1-10-1-0061.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25180079','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25180079"><span><span class="hlt">Electronic</span> cigarette effectiveness and abuse liability: predicting and regulating nicotine <span class="hlt">flux</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shihadeh, Alan; Eissenberg, Thomas</p> <p>2015-02-01</p> <p><span class="hlt">Electronic</span> cigarettes (ECIGs) comprise an aerosolized nicotine delivery product category that provides consumers with probably unprecedented control over extensive features and operating conditions, allowing a wide range of nicotine yields to be obtained. Depending on the combination of such ECIG variables as electrical power input, geometry, liquid composition, and puff behavior, ECIG users can extract in a few puffs far more or far less nicotine than with a conventional combustible cigarette. These features of ECIG design and use present challenges for public health policy, central among which is the question of how to regulate nicotine delivery. In this commentary, we propose a conceptual framework intended to provide a convenient approach for evaluating and regulating the nicotine emitted from ECIGs. This framework employs nicotine <span class="hlt">flux</span> to account for the total dose and rate at which nicotine reaches the user, 2 key factors in drug abuse liability. The nicotine <span class="hlt">flux</span> is the nicotine emitted per puff second (e.g., mg/s) by a given ECIG design under given use conditions, and it can be predicted accurately using physical principles. We speculate that if the <span class="hlt">flux</span> is too low, users likely will abandon the device and maintain conventional tobacco product use. Also, we speculate that if the <span class="hlt">flux</span> is too high, individuals may suffer toxic side effects and/or the device may have higher-than-necessary abuse liability. By considering ECIG design, operation conditions, liquid composition, and puff behavior variables in combination, we illustrate how ECIG specifications can be realistically mandated to result in a target <span class="hlt">flux</span> range. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950060553&hterms=Noriega&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DNoriega','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950060553&hterms=Noriega&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DNoriega"><span>Theoretical position-velocity diagrams of <span class="hlt">flux</span>, <span class="hlt">electron</span> density, and <span class="hlt">electron</span> temperature in Herbig-Haro objects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Indebetouw, Remy; Noriega-Crespo, Alberto</p> <p>1995-01-01</p> <p>Many features of Herbig-Haro objects can be reproduced using a kinematical bow shock model. We use the model to generate position-velocity (PV) diagrams of <span class="hlt">flux</span> in H-alpha (O I) lambda lambda 6300+63, (S II) lambda lambda 6716+31, (O III) lambda lambda 4959+5007, and (C I) lambda lambda 9823+50, line ratios of (O I)/H-alpha, (O I)/(S II), (S II)/H-alpha, H-alpha(S II), and (O III)/H-alpha, <span class="hlt">electron</span> density N(sub e), and <span class="hlt">electron</span> temperature T(sub e). We show how position-velocity diagrams of N(sub e) and <span class="hlt">flux</span> vary with shock velocity. By matching the diagrams from single lines, the line ratios, and N(sub e) with observations, we determined a narrow range of shock parameters for HH 1F, 2(A' + H), and 43 (B + C). We model the N(sub e) features of HH 2(A' + H) as a superposition of two bowshocks. We also show that the effects of slight misalignments of the two diagrams to be divided can produce artifacts in the line ratios and N(sub e) which obliterate the physical features. We show that N(sub e) in HH 1 can only be explained using the kinematical model by taking these misalignments into account.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28537305','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28537305"><span>Study of antiradical mechanisms with dihydroxybenzenes using reaction force and reaction <span class="hlt">electronic</span> <span class="hlt">flux</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ortega-Moo, Cristina; Durán, Rocio; Herrera, Bárbara; Gutiérrez-Oliva, Soledad; Toro-Labbé, Alejandro; Vargas, Rubicelia</p> <p>2017-06-07</p> <p>Phenolic compounds represent an important category of antioxidants because they help inhibit the oxidation process of organic compounds, while also acting as antiradicals in many biological processes. In this work, we analyze the transfer mechanisms for a set of catechols and resorcinols of a single <span class="hlt">electron</span>, proton and hydrogen, with the radical peroxyl (˙OOH) and with different <span class="hlt">electron</span> withdrawing and donating groups as substituents. By using the M05-2X exchange correlation functional within the Density Functional Theory framework combined with the 6-311++G(d,p) basis set, we were able to compute the Gibbs free energies for all mechanisms and compounds. According to the thermodynamic results, the hydrogen atom transfer mechanism was the most favorable. Therefore, this mechanism with substituents -CH3 and -COH in catechol and resorcinol was analyzed, using the reaction force and reaction <span class="hlt">electronic</span> <span class="hlt">flux</span> to characterize the structural and <span class="hlt">electronic</span> changes that take place during the reaction. Our results show that <span class="hlt">electron</span> donating groups favor <span class="hlt">electronic</span> changes along the reaction path, increasing the spontaneity of the hydrogen atom transfer mechanism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSM21A..02C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSM21A..02C"><span>Van Allen Probes ECT/MagEIS Background Corrected <span class="hlt">Electron</span> <span class="hlt">Flux</span> Measurements: Methods and Initial Findings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Claudepierre, S. G.; O'Brien, T. P., III; Blake, J. B.; Fennell, J.; Looper, M. D.; Clemmons, J. H.; Roeder, J. L.; Mazur, J. E.; Mulligan, T. L.</p> <p>2014-12-01</p> <p>We present results from the Magnetic <span class="hlt">Electron</span> Ion Spectrometer (MagEIS) instrument, part ofthe Energetic Composition and Thermal Plasma (ECT) Suite, onboard the NASA Van AllenProbes spacecraft. The ECT/MagEIS instrument measures radiation belt <span class="hlt">electrons</span> in the ~20-4000 keV energy range and protons in the ~60-1000 keV energy range, with high resolution inboth energy and pitch-angle. In addition, the MagEIS <span class="hlt">electron</span> measurement technique allowsfor a full quantification of the source(s) of background contamination in the measurement.MagEIS is thus able to make clean, reliable <span class="hlt">electron</span> <span class="hlt">flux</span> observations in the presence of strongpenetrating backgrounds, for example, contamination from relativistic protons in the inner zoneand inner slot region. We summarize our background correction algorithm, describe the varioussources of background contamination, and present an overview of our initial findings using thebackground corrected data set. Understanding the causes and effects of backgroundcontamination in the MagEIS <span class="hlt">electron</span> data set is crucial for the interpretation and proper use ofsuch data. The techniques described will facilitate new investigations into the dynamics of theEarth's <span class="hlt">electron</span> radiation belts, which have thus far not been possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.8448B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.8448B"><span><span class="hlt">Electron</span> <span class="hlt">flux</span> dropouts at Geostationary Earth Orbit: Occurrences, magnitudes, and main driving factors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boynton, R. J.; Mourenas, D.; Balikhin, M. A.</p> <p>2016-09-01</p> <p>Large decreases of daily average <span class="hlt">electron</span> <span class="hlt">flux</span>, or dropouts, were investigated for a range of energies from 24.1 keV to 2.7 MeV, on the basis of a large database of 20 years of measurements from Los Alamos National Laboratory (LANL) geosynchronous satellites. Dropouts were defined as <span class="hlt">flux</span> decreases by at least a factor 4 in 1 day, or a factor 9 in 2 days during which a decrease by at least a factor of 2.5 must occur each day. Such decreases were automatically identified. As a first result, a comprehensive statistics of the mean waiting time between dropouts and of their mean magnitude has been provided as a function of <span class="hlt">electron</span> energy. Moreover, the Error Reduction Ratio analysis was applied to explore the possible nonlinear relationships between <span class="hlt">electron</span> dropouts and various exogenous factors, such as solar wind and geomagnetic indices. Different dropout occurrences and magnitudes were found in three distinct energy ranges, lower than 100 keV, 100-600 keV, and larger than 600 keV, corresponding to different groups of drivers and loss processes. Potential explanations have been outlined on the basis of the statistical results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvA..92f2706R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvA..92f2706R"><span>Modification of the quantum mechanical <span class="hlt">flux</span> formula for <span class="hlt">electron</span>-hydrogen ionization through Bohm's velocity field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Randazzo, J. M.; Ancarani, L. U.</p> <p>2015-12-01</p> <p>For the single differential cross section (SDCS) for hydrogen ionization by <span class="hlt">electron</span> impact (e -H problem), we propose a correction to the <span class="hlt">flux</span> formula given by R. Peterkop [Theory of Ionization of Atoms by <span class="hlt">Electron</span> Impact (Colorado Associated University Press, Boulder, 1977)]. The modification is based on an alternative way of defining the kinetic energy fraction, using Bohm's definition of velocities instead of the usual asymptotic kinematical, or geometrical, approximation. It turns out that the solution-dependent, modified energy fraction is equally related to the components of the probability <span class="hlt">flux</span>. Compared to what is usually observed, the correction yields a finite and well-behaved SDCS value in the asymmetrical situation where one of the continuum <span class="hlt">electrons</span> carries all the energy while the other has zero energy. We also discuss, within the S -wave model of the e -H ionization process, the continuity of the SDCS derivative at the equal energy sharing point, a property not so clearly observed in published benchmark results obtained with integral and S -matrix formulas with unequal final states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26360373','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26360373"><span>Alterations in the NF2/<span class="hlt">LATS</span>1/<span class="hlt">LATS</span>2/YAP Pathway in Schwannomas.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Oh, Ji-Eun; Ohta, Takashi; Satomi, Kaishi; Foll, Matthieu; Durand, Geoffroy; McKay, James; Le Calvez-Kelm, Florence; Mittelbronn, Michel; Brokinkel, Benjamin; Paulus, Werner; Ohgaki, Hiroko</p> <p>2015-10-01</p> <p>Schwannomas are benign nerve sheath tumors composed of well-differentiated Schwann cells. Other than frequent NF2 (neurofibromatosis type 2) mutations (50%-60%), their molecular pathogenesis is not fully understood. <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 are downstream molecules of NF2 and are negative regulators of the yes-associated protein (YAP) oncogene in the Hippo signaling pathway. We assessed mutations of the NF2, <span class="hlt">LATS</span>1, and <span class="hlt">LATS</span>2 genes, promoter methylation of <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2, and expression of YAP and phosphorylated YAP in 82 cases of sporadic schwannomas. Targeted sequencing using the Ion Torrent Proton instrument revealed NF2 mutations in 45 cases (55%), <span class="hlt">LATS</span>1 mutations in 2 cases (2%), and <span class="hlt">LATS</span>2 mutations in 1 case (1%) of schwannoma. Methylation-specific polymerase chain reaction showed promoter methylation of <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 in 14 cases (17%) and 25 cases (30%), respectively. Overall, 62 cases (76%) had at least 1 alteration in the NF2, <span class="hlt">LATS</span>1, and/or <span class="hlt">LATS</span>2 genes. Immunohistochemistry revealed nuclear YAP expression in 18 of 42 cases of schwannoma (43%) and reduced cytoplasmic phosphorylated YAP expression in 15 of 49 cases of schwannoma (31%), all of which had at least 1 alteration in the NF2, <span class="hlt">LATS</span>1, and/or <span class="hlt">LATS</span>2 genes. These results suggest that an abnormal Hippo signaling pathway is involved in the pathogenesis of most sporadic schwannomas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSM21A2456P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSM21A2456P"><span>ULF waves: the main periodicities and their relationships with solar wind structures and magnetospheric <span class="hlt">electron</span> <span class="hlt">flux</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Piersanti, M.; Alberti, T.; Lepreti, F.; Vecchio, A.; Villante, U.; Carbone, V.; Waters, C. L.</p> <p>2015-12-01</p> <p>We use high latitude ULF wave power in the range 2-7 mHz (Pc5 geomagnetic micropulsations), solar wind speed and dynamic pressure, and relativistic magnetospheric <span class="hlt">electron</span> <span class="hlt">flux</span> (E > 0.6 MeV), in the period January - September 2008, in order to detect typical periodicities and physical mechanisms involved into the solar wind-magnetosphere coupling during the declining phase of the 23th solar cycle. Using the Empirical Mode Decomposition (EMD) and applying a statistical test and cross-correlation analysis,we investigate the timescales and the physical mechanisms involved into the solar wind-magnetosphere coupling.Summarizing, we obtain the following results:1. We note the existence of two different timescales into the four datasets which are related to the short-term dynamics, with a characteristic timescale τ<3 days, and to the longer timescale dynamics, with a timescale between 7 and 80 days. The short-term variations could be related to the fluctuations around a characteristic mean value, while longer timescales dynamics can be associated with solar rotational periodicity and mechanisms regarding the occurrence of high-speed streams and corotating interaction regions but also with stream-stream interactions and synodic solar rotation.2. The cross-correlation analysis highlights the relevant role of the dynamical coupling between solar wind and magnetosphere via pressure balance and direct transfer of compressional waves into the magnetosphere. Moreover, it shows that the Kelvin-Helmholtz instability is not the primary source of geomagnetic ultra-low frequency wave activity. These results are in agreement with previous works [Engebretson et al, 1998].3. The cross-correlation coefficient between Pc5 wave power and relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> longscale reconstructions shows that Pc5 wave activity leads enhancements in magnetospheric <span class="hlt">electron</span> <span class="hlt">flux</span> to relativistic energy with a characteristic time delay of about 54 hours, which is in agreement with the lag of about 2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011crpa.conf..556P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011crpa.conf..556P"><span>Pulsar <span class="hlt">Electrons</span> Detection in AMS-02 Experiment. Model Status and Discovery Potential</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pochon, Jonathan</p> <p>2011-06-01</p> <p>The measurements of cosmic rays <span class="hlt">electrons</span> (e±) have begun a new era a few years ago with high precision experiments like PAMELA and Fermi-<span class="hlt">LAT</span>. Both experiments show an excess above 10 GeV. Studying Fermi-<span class="hlt">LAT</span> data, the total <span class="hlt">electron</span> <span class="hlt">flux</span> seems to be steeper than expected. While these new measurements have not closed the debate, results from AMS-02 are expected to reach the accuracy needed to determine a full description of these excesses, and hopefully give some evidence on the possible source. We will present in this paper, the AMS-02 capacity in the case of positrons produced by pulsars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22102203','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22102203"><span>Energy distribution of <span class="hlt">electron</span> <span class="hlt">flux</span> at electrodes in a low pressure capacitively coupled plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rauf, Shahid; Dorf, Leonid; Kenney, Jason; Collins, Ken</p> <p>2013-01-14</p> <p>A one-dimensional particle-in-cell (PIC) model is used to examine the energy distribution of <span class="hlt">electron</span> <span class="hlt">flux</span> at electrodes [labeled g{sub e}({epsilon},t), where {epsilon} is energy and t is time] in a low pressure 60 MHz capacitively coupled Ar discharge. The effect of gas pressure and an auxiliary DC voltage on g{sub e}({epsilon},t) is also investigated. It is found that the <span class="hlt">electrons</span> only leave the plasma for a short time period during the radio-frequency (RF) cycle when the sheath collapses at the electrode. Furthermore, majority of the exiting <span class="hlt">electrons</span> have energies below 10 eV with a distribution g{sub e}({epsilon},t) that is narrow in both energy and time. At relatively high pressures ({>=}4.67 Pa for the conditions considered), the relationship between the time-average distribution g{sub e}({epsilon}) and <span class="hlt">electron</span> temperature in the plasma (T{sub e}) can be easily established. Below 4.67 Pa, kinetic effects become important, making it difficult to interpret g{sub e}({epsilon}) in terms of T{sub e}. At low pressures, g{sub e}({epsilon},t) is found to broaden in both energy and time except for a narrow pressure range around 1.2 Pa where the distribution narrows temporally. These low pressure kinetic phenomena are observed when the <span class="hlt">electrons</span> can be accelerated by expanding sheaths to speeds that allow them to traverse the inter-electrode distance quickly (<1.5 RF cycles for conditions considered) and when <span class="hlt">electrons</span> undergo few collisions during this excursion. The mean energy of exiting <span class="hlt">electrons</span> increases with decreasing gas pressure, especially below 1.0 Pa, due to higher T{sub e} and secondary <span class="hlt">electrons</span> retaining a larger fraction of the energy they gained during initial sheath acceleration. For the relatively small DC voltages examined ( Double-Vertical-Line V{sub dc} Double-Vertical-Line /V{sub rf} {<=} 0.15), the application of a negative DC voltage on an electrode decreases the <span class="hlt">electron</span> <span class="hlt">flux</span> there but has a weak impact on the g{sub e} profile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ascl.soft09011L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ascl.soft09011L"><span>FLaapLUC: Fermi-<span class="hlt">LAT</span> automatic aperture photometry light curve</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lenain, Jean-Philippe</p> <p>2017-09-01</p> <p>Most high energy sources detected with Fermi-<span class="hlt">LAT</span> are blazars, which are highly variable sources. High cadence long-term monitoring simultaneously at different wavelengths being prohibitive, the study of their transient activities can help shed light on our understanding of these objects. The early detection of such potentially fast transient events is the key for triggering follow-up observations at other wavelengths. FLaapLUC (Fermi-<span class="hlt">LAT</span> automatic aperture photometry Light C↔Urve) uses the simple aperture photometry approach to effectively detect relative <span class="hlt">flux</span> variations in a set of predefined sources and alert potential users. Such alerts can then be used to trigger observations of these sources with other facilities. The FLaapLUC pipeline is built on top of the Science Tools provided by the Fermi-<span class="hlt">LAT</span> collaboration and quickly generates short- or long-term Fermi-<span class="hlt">LAT</span> light curves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT.......119R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT.......119R"><span>Oxygen <span class="hlt">flux</span> and dielectric response study of Mixed Ionic-<span class="hlt">Electronic</span> Conducting (MIEC) heterogeneous functional materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rabbi, Fazle</p> <p></p> <p>Dense mixed ionic-<span class="hlt">electronic</span> conducting (MIEC) membranes consisting of ionic conductive perovskite-type and/or fluorite-type oxides and high <span class="hlt">electronic</span> conductive spinel type oxides, at elevated temperature can play a useful role in a number of energy conversion related systems including the solid oxide fuel cell (SOFC), oxygen separation and permeation membranes, partial oxidization membrane reactors for natural gas processing, high temperature electrolysis cells, and others. This study will investigate the impact of different heterogeneous characteristics of dual phase ionic and <span class="hlt">electronic</span> conductive oxygen separation membranes on their transport mechanisms, in an attempt to develop a foundation for the rational design of such membranes. The dielectric behavior of a material can be an indicator for MIEC performance and can be incorporated into computational models of MIEC membranes in order to optimize the composition, microstructure, and ultimately predict long term membrane performance. The dielectric behavior of the MIECs can also be an indicator of the transport mechanisms and the parameters they are dependent upon. For this study we chose a dual phase MIEC oxygen separation membrane consisting of an ionic conducting phase: gadolinium doped ceria-Ce0.8 Gd0.2O2 (GDC) and an <span class="hlt">electronic</span> conductive phase: cobalt ferrite-CoFe2O4 (CFO). The membranes were fabricated from mixtures of Nano-powder of each of the phases for different volume percentages, sintered with various temperatures and sintering time to form systematic micro-structural variations, and characterized by structural analysis (XRD), and micro-structural analysis (SEM-EDS). Performance of the membranes was tested for variable partial pressures of oxygen across the membrane at temperatures from 850°C-1060°C using a Gas Chromatography (GC) system. Permeated oxygen did not directly correlate with change in percent mixture. An intermediate mixture 60%GDC-40%CFO had the highest <span class="hlt">flux</span> compared to the 50%GDC</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1356602-fermi-lat-suzaku-observations-radio-galaxy-centaurus','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1356602-fermi-lat-suzaku-observations-radio-galaxy-centaurus"><span>Fermi-<span class="hlt">LAT</span> and Suzaku observations of the radio galaxy Centaurus B</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Katsuta, J.; Tanaka, Y. T.; Stawarz, Ł.; ...</p> <p>2013-01-28</p> <p>Centaurus B is a nearby radio galaxy positioned in the southern hemisphere close to the Galactic plane. Here, in this work, we present a detailed analysis of about 43 months of accumulated Fermi-<span class="hlt">LAT</span> data of the γ-ray counterpart of the source initially reported in the 2nd Fermi-<span class="hlt">LAT</span> catalog, and of newly acquired Suzaku X-ray data. We confirm its detection at GeV photon energies and analyze the extension and variability of the γ-ray source in the <span class="hlt">LAT</span> dataset, in which it appears as a steady γ-ray emitter. The X-ray core of Centaurus B is detected as a bright source of amore » continuum radiation. We do not detect, however, any diffuse X-ray emission from the known radio lobes, with the provided upper limit only marginally consistent with the previously claimed ASCA <span class="hlt">flux</span>. Two scenarios that connect the X-ray and γ-ray properties are considered. In the first one, we assume that the diffuse non-thermal X-ray emission component is not significantly below the derived Suzaku upper limit. In this case, modeling the inverse-Compton emission shows that the observed γ-ray <span class="hlt">flux</span> of the source may in principle be produced within the lobes. This association would imply that efficient in-situ acceleration of the radiating <span class="hlt">electrons</span> is occurring and that the lobes are dominated by the pressure from the relativistic particles. In the second scenario, with the diffuse X-ray emission well below the Suzaku upper limits, the lobes in the system are instead dominated by the magnetic pressure. In this case, the observed γ-ray <span class="hlt">flux</span> is not likely to be produced within the lobes, but instead within the nuclear parts of the jet. In conclusion, by means of synchrotron self-Compton modeling, we show that this possibility could be consistent with the broad-band data collected for the unresolved core of Centaurus B, including the newly derived Suzaku spectrum.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5732854','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5732854"><span>Measurements of fluctuations in the <span class="hlt">flux</span> of runaway <span class="hlt">electrons</span> to the PLT tokamak limiter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Barnes, C.W.; Strachan, J.D.</p> <p>1983-09-01</p> <p>Fluctuations in the <span class="hlt">flux</span> of runaway <span class="hlt">electrons</span> to the limiter are measured during many PLT (Princeton Large Torus) discharges. Oscillations at 60, 120, and 720 Hz are driven by variations in the vertical magnetic field which moves the plasma major radius. Fluctuations are seen with frequencies in the range of 2--20 kHz because of magnetohydrodynamic (MHD) magnetic islands which extend to the plasma surface. A continuous spectrum of fluctuations is observed up to 200 kHz which correlates with drift-wave turbulence. The magnitude of the driven fluctuations can be used to measure transport properties of the runaway <span class="hlt">electrons</span>. The amplitude of <span class="hlt">electron</span> motion due to the MHD and drift-wave oscillations, and hence a measure of the radial size of the instability, can be determined as a function of frequency. The slope of the frequency power spectrum of the drift-wave-induced fluctuations steepens with increasing runaway-<span class="hlt">electron</span> drift orbit displacement during the current drop at the end of the discharge, and as the power in the MHD oscillations increases. A magnetic probe is used to confirm the presence of oscillating magnetic fields capable of perturbing the <span class="hlt">electron</span> orbits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5183814','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5183814"><span>Measurements of fluctuations in the <span class="hlt">flux</span> of runaway <span class="hlt">electrons</span> to the PLT limiter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Barnes, C.W.; Strachan, J.D.</p> <p>1982-07-01</p> <p>Fluctuations in the <span class="hlt">flux</span> of runaway <span class="hlt">electrons</span> to the limiter have been measured during many PLT discharges. Oscillations at 60, 120, and 720 Hz are driven by variations in the vertical magnetic field which moves the plasma major radius. Fluctuations are seen in the range of 2 ..-->.. 20 kHz due to MHD magnetic islands which extend to the plasma surface. A continuous spectrum of fluctuations is observed up to 200 kHz which correlates with drift-wave turbulence. The magnitude of the driven fluctuations can be used to measure transport properties of the runaway <span class="hlt">electrons</span>. The amplitude of <span class="hlt">electron</span> motion due to the MHD and drift-wave oscillations, and hence a measure of the radial size of the instability, can be determined as a function of frequency. The slope of the frequency power spectrum of the drift-wave-induced fluctuations steepens with increasing runaway <span class="hlt">electron</span> drift orbit displacement during the current drop at the end of the discharge, and as the power in the MHD oscillations increases. A magnetic probe was used to confirm the presence of oscillating magnetic fields capable of perturbing the <span class="hlt">electron</span> orbits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008ApJ...684..790A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008ApJ...684..790A"><span>An Upper Limit on the <span class="hlt">Electron</span>-Neutrino <span class="hlt">Flux</span> from the HiRes Detector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abbasi, R. U.; Abu-Zayyad, T.; Allen, M.; Amann, J. F.; Archbold, G.; Belov, K.; Belz, J. W.; Ben Zvi, S. Y.; Bergman, D. R.; Biesiadecka, A.; Blake, S. A.; Boyer, J. H.; Brusova, O. A.; Burt, G. W.; Cannon, C.; Cao, Z.; Deng, W.; Fedorova, Y.; Findlay, J.; Finley, C. B.; Gray, R. C.; Hanlon, W. F.; Hoffman, C. M.; Holzscheiter, M. H.; Hughes, G.; Hüntemeyer, P.; Ivanov, D.; Jones, B. F.; Jui, C. C. H.; Kim, K.; Kirn, M. A.; Knapp, B. C.; Loh, E. C.; Maestas, M. M.; Manago, N.; Mannel, E. J.; Marek, L. J.; Martens, K.; Matthews, J. A. J.; Matthews, J. N.; Moore, S. A.; O'Neill, A.; Painter, C. A.; Perera, L.; Reil, K.; Riehle, R.; Roberts, M. D.; Rodriguez, D.; Sasaki, M.; Schnetzer, S. R.; Scott, L. M.; Seman, M.; Sinnis, G.; Smith, J. D.; Snow, R.; Sokolsky, P.; Song, C.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Thomas, J. R.; Thomas, S. B.; Thomson, G. B.; Tupa, D.; Wiencke, L. R.; Zech, A.; Zhang, X.</p> <p>2008-09-01</p> <p>Air-fluorescence detectors such as the High Resolution Fly's Eye (HiRes) detector are very sensitive to upward-going, Earth-skimming ultra-high-energy <span class="hlt">electron</span>-neutrino-induced showers. This is due to the relatively large interaction cross sections of these high-energy neutrinos and to the Landau-Pomeranchuk-Migdal (LPM) effect. The LPM effect causes a significant decrease in the cross sections for bremsstrahlung and pair production, allowing charged-current <span class="hlt">electron</span>-neutrino-induced showers occurring deep in the Earth's crust to be detectable as they exit the Earth into the atmosphere. A search for upward-going neutrino-induced showers in the HiRes-II monocular data set has yielded a null result. From an LPM calculation of the energy spectrum of charged particles as a function of primary energy and depth for <span class="hlt">electron</span>-induced showers in rock, we calculate the shape of the resulting profile of these showers in air. We describe a full detector Monte Carlo simulation to determine the detector response to upward-going <span class="hlt">electron</span>-neutrino-induced cascades and present an upper limit on the <span class="hlt">flux</span> of <span class="hlt">electron</span> neutrinos.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008APS..APR.B8007S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008APS..APR.B8007S"><span>An upper limit on the <span class="hlt">electron</span>-neutrino <span class="hlt">flux</span> from the HiRes detector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scott, Lauren</p> <p>2008-04-01</p> <p>Air-fluorescence detectors such as the High Resolution Fly's Eye (HiRes) detector are very sensitive to upward-going, Earth-skimming ultrahigh energy <span class="hlt">electron</span>-neutrino-induced showers. This is due to the relatively large interaction cross sections of these high-energy neutrinos and to the Landau-Pomeranchuk-Migdal (LPM) effect. The LPM effect causes a significant decrease in the cross sections for bremsstrahlung and pair production, allowing charged-current <span class="hlt">electron</span>-neutrino-induced showers occurring deep in the Earth's crust to be detectable as they exit the Earth into the atmosphere. A search for upward-going neutrino-induced showers in the HiRes-II monocular dataset has yielded a null result. From an LPM calculation of the energy spectrum of charged particles as a function of primary energy and depth for <span class="hlt">electron</span>-induced showers in rock, we calculate the shape of the resulting profile of these showers in air. We describe a full detector Monte Carlo simulation to determine the detector response to upward-going <span class="hlt">electron</span>-neutrino-induced cascades and present an upper limit on the <span class="hlt">flux</span> of <span class="hlt">electron</span>-neutrinos.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008ICRC....5.1377S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008ICRC....5.1377S"><span>An upper limit on the <span class="hlt">electron</span>-neutrino <span class="hlt">flux</span> from the HiRes instrument</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scott, L. M.</p> <p></p> <p>Air-fluorescence detectors such as the High Resolution Fly's Eye (HiRes) instrument are very sensitive to upward-going, Earth-skimming ultrahigh energy <span class="hlt">electron</span>-neutrino-induced showers. This is due to the relatively large interaction cross sections of these high-energy neutrinos and the Landau-Pomeranchuk-Migdal (LPM) effect, which is responsible for a significant decrease in the cross sections for bremsstrahlung and pair production, rendering charged-current <span class="hlt">electron</span>-neutrino-induced showers occurring deep in the Earth's crust detectable as they exit the Earth into the atmosphere. The search for upward-going neutrino-induced showers in the entire HiRes-II monocular dataset has yielded a null result. From a full LPM calculation of the energy spectrum of charged particles as a function of primary energy and depth for <span class="hlt">electron</span>-induced showers in rock, we calculate the resulting profile of these showers in air. A full detector Monte Carlo simulation to determine the detector response to upward-going <span class="hlt">electron</span>-neutrino-induced cascades is described and an upper limit on the <span class="hlt">flux</span> of <span class="hlt">electron</span>-neutrinos is given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760008619&hterms=qualitative+observation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dqualitative%2Bobservation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760008619&hterms=qualitative+observation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dqualitative%2Bobservation"><span>Coordinated ATS-5 <span class="hlt">electron</span> <span class="hlt">flux</span> and simultaneous auroral observations, appendix B. [of magnetic storms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mende, S. B.; Shelley, E. G.</p> <p>1975-01-01</p> <p>All Sky Cameras (ASCA) magnetosphere observations were made at the field line conjugate of the ATS-5 Satellite. The magnetosphere region examined was L=5 to L=11. The correlation of the auroras observed by the ASCA's and the magnetospheric trapped <span class="hlt">fluxes</span> was studied. It is shown that auroral forms are not simply correlated with the synchronous altitude <span class="hlt">electron</span> <span class="hlt">fluxes</span>. The presence of hot plasma at the ATS-5 satellite is a necessary but not sufficient condition for the occurrence of local auroras. On quiet days the hot plasma does not penetrate into the magnetosphere far enough to reach the ATS-5 orbit. Under these conditions no auroras are observed at the field line conjugate, but auroras are usually observed on higher latitude field lines. On more disturbed days, auroral arcs are observed at lower latitudes when the plasma sheet penetrates into the ATS-5 orbit. Significant qualitative correlation between the ASCA data and the trapped <span class="hlt">fluxes</span> was observed when a local plasma injection event occurred near ATS-5. Magnetograms are shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1355151','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1355151"><span>Local H i emissivity measured with <i>FERMI</i>-<span class="hlt">LAT</span> and implications for Cosmic-ray spectra</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Casandjian, Jean -Marc</p> <p>2015-06-20</p> <p>Cosmic-ray (CR) <span class="hlt">electrons</span> and nuclei interact with the Galactic interstellar gas and produce high-energy γ-rays. The γ-ray emission rate per hydrogen atom, called emissivity, provides a unique indirect probe of the CR <span class="hlt">flux</span>. We present the measurement and the interpretation of the emissivity in the solar neighborhood for γ-ray energy from 50 MeV to 50 GeV. We analyzed a subset of 4 yr of observations from the Large Area Telescope (<span class="hlt">LAT</span>) aboard the <i>Fermi Gamma-ray Space Telescope</i> (<i>Fermi</i>) restricted to absolute latitudes $10^\\circ \\lt | b| \\lt 70^\\circ $. From a fit to the <span class="hlt">LAT</span> data including atomic, molecular, and ionized hydrogen column density templates, as well as a dust optical depth map, we derived the emissivities, the molecular hydrogen–to–CO conversion factor ${X}_{\\mathrm{CO}}=(0.902\\pm 0.007)\\times {10}^{20}$ cm–2 (K km s–1)–1, and the dust-to-gas ratio ${X}_{\\mathrm{DUST}}=(41.4\\pm 0.3)\\times {10}^{20}$ cm–2 mag–1. Moreover, we detected for the first time γ-ray emission from ionized hydrogen. We compared the extracted emissivities to those calculated from γ-ray production cross sections and to CR spectra measured in the heliosphere. We observed that the experimental emissivities are reproduced only if the solar modulation is accounted for. This provides a direct detection of solar modulation observed previously through the anticorrelation between CR <span class="hlt">fluxes</span> and solar activity. Lastly, we fitted a parameterized spectral form to the heliospheric CR observations and to the <i>Fermi</i>-<span class="hlt">LAT</span> emissivity and obtained compatible local interstellar spectra for proton and helium kinetic energy per nucleon between between 1 and 100 GeV and for electron–positrons between 0.1 and 100 GeV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357571-constraints-cosmological-dark-matter-annihilation-from-fermi-lat-isotropic-diffuse-gamma-ray-measurement','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357571-constraints-cosmological-dark-matter-annihilation-from-fermi-lat-isotropic-diffuse-gamma-ray-measurement"><span>Constraints on cosmological dark matter annihilation from the Fermi-<span class="hlt">LAT</span> isotropic diffuse gamma-ray measurement</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Abdo, A. A.; Ackermann, M.; Ajello, M.; ...</p> <p>2010-04-01</p> <p>The first published Fermi large area telescope (Fermi-<span class="hlt">LAT</span>) measurement of the isotropic diffuse gamma-ray emission is in good agreement with a single power law, and is not showing any signature of a dominant contribution from dark matter sources in the energy range from 20 to 100 GeV. Here, we use the absolute size and spectral shape of this measured <span class="hlt">flux</span> to derive cross section limits on three types of generic dark matter candidates: annihilating into quarks, charged leptons and monochromatic photons. Predicted gamma-ray <span class="hlt">fluxes</span> from annihilating dark matter are strongly affected by the underlying distribution of dark matter, and bymore » using different available results of matter structure formation we assess these uncertainties. We also quantify how the dark matter constraints depend on the assumed conventional backgrounds and on the Universe's transparency to high-energy gamma-rays. In reasonable background and dark matter structure scenarios (but not in all scenarios we consider) it is possible to exclude models proposed to explain the excess of <span class="hlt">electrons</span> and positrons measured by the Fermi-<span class="hlt">LAT</span> and PAMELA experiments. Derived limits also start to probe cross sections expected from thermally produced relics (e.g. in minimal supersymmetry models) annihilating predominantly into quarks. Finally, for the monochromatic gamma-ray signature, the current measurement constrains only dark matter scenarios with very strong signals.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1357571','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1357571"><span>Constraints on cosmological dark matter annihilation from the Fermi-<span class="hlt">LAT</span> isotropic diffuse gamma-ray measurement</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.; Ackermann, M.; Ajello, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bouvier, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Burnett, T. H.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Carrigan, S.; Casandjian, J. M.; Cecchi, C.; Çelik, Ö.; Chekhtman, A.; Cheung, C. C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; Dermer, C. D.; Angelis, A. de; Palma, F. de; Digel, S. W.; Silva, E. do Couto e.; Drell, P. S.; Dubois, R.; Dumora, D.; Edmonds, Y.; Farnier, C.; Favuzzi, C.; Fegan, S. J.; Focke, W. B.; Fortin, P.; Frailis, M.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; Grove, J. E.; Guillemot, L.; Guiriec, S.; Gustafsson, M.; Hadasch, D.; Harding, A. K.; Horan, D.; Hughes, R. E.; Johnson, A. S.; Johnson, W. N.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knödlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Garde, M. Llena; Longo, F.; Loparco, F.; Lott, B.; Lovellette, M. N.; Lubrano, P.; Makeev, A.; Mazziotta, M. N.; McEnery, J. E.; Meurer, C.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nolan, P. L.; Norris, J. P.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; Ormes, J. F.; Paneque, D.; Panetta, J. H.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Rainò, S.; Rando, R.; Reimer, A.; Reimer, O.; Reposeur, T.; Rodriguez, A. Y.; Roth, M.; Sadrozinski, H. F. -W; Sander, A.; Parkinson, P. M. Saz; Scargle, J. D.; Sellerholm, A.; Sgrò, C.; Siskind, E. J.; Smith, P. D.; Spandre, G.; Spinelli, P.; Starck, J. -L; Strickman, M. S.; Suson, D. J.; Takahashi, H.; Tanaka, T.; Thayer, J. B.; Thayer, J. G.; Torres, D. F.; Uchiyama, Y.; Usher, T. L.; Vasileiou, V.; Vilchez, N.; Vitale, V.; Waite, A. P.; Wang, P.; Winer, B. L.; Wood, K. S.; Ylinen, T.; Zaharijas, G.; Ziegler, M.</p> <p>2010-04-01</p> <p>The first published Fermi large area telescope (Fermi-<span class="hlt">LAT</span>) measurement of the isotropic diffuse gamma-ray emission is in good agreement with a single power law, and is not showing any signature of a dominant contribution from dark matter sources in the energy range from 20 to 100 GeV. Here, we use the absolute size and spectral shape of this measured <span class="hlt">flux</span> to derive cross section limits on three types of generic dark matter candidates: annihilating into quarks, charged leptons and monochromatic photons. Predicted gamma-ray <span class="hlt">fluxes</span> from annihilating dark matter are strongly affected by the underlying distribution of dark matter, and by using different available results of matter structure formation we assess these uncertainties. We also quantify how the dark matter constraints depend on the assumed conventional backgrounds and on the Universe's transparency to high-energy gamma-rays. In reasonable background and dark matter structure scenarios (but not in all scenarios we consider) it is possible to exclude models proposed to explain the excess of <span class="hlt">electrons</span> and positrons measured by the Fermi-<span class="hlt">LAT</span> and PAMELA experiments. Derived limits also start to probe cross sections expected from thermally produced relics (e.g. in minimal supersymmetry models) annihilating predominantly into quarks. Finally, for the monochromatic gamma-ray signature, the current measurement constrains only dark matter scenarios with very strong signals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhRvS..16l0701Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhRvS..16l0701Y"><span>Maximizing spectral <span class="hlt">flux</span> from self-seeding hard x-ray free <span class="hlt">electron</span> lasers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Xi; Shvyd'ko, Yuri</p> <p>2013-12-01</p> <p>Fully coherent x rays can be generated by self-seeding x-ray free <span class="hlt">electron</span> lasers (XFELs). Self-seeding by a forward Bragg diffraction (FBD) monochromator has been recently proposed [G. Geloni, V. Kocharyan, and E. Saldin, J. Mod. Opt. 58, 1391 (2011)JMOPEW0950-034010.1080/09500340.2011.586473] and demonstrated [J. Amann , Nat. Photonics 6, 693 (2012)NPAHBY1749-488510.1038/nphoton.2012.180]. Characteristic time T0 of FBD determines the power, spectral, and time characteristics of the FBD seed [Yu. Shvyd’ko and R. Lindberg, Phys. Rev. ST Accel. Beams 15, 100702 (2012)PRABFM1098-440210.1103/PhysRevSTAB.15.100702]. Here we show that for a given <span class="hlt">electron</span> bunch with duration σe the spectral <span class="hlt">flux</span> of the self-seeding XFEL can be maximized, and the spectral bandwidth can be respectively minimized by choosing T0˜σe/π and by optimizing the <span class="hlt">electron</span> bunch delay τe. The choices of T0 and τe are not unique. In all cases, the maximum value of the spectral <span class="hlt">flux</span> and the minimum bandwidth are primarily determined by σe. Two-color seeding takes place if T0≪σe/π. The studies are performed, for a Gaussian <span class="hlt">electron</span> bunch distribution with the parameters, close to those used in the short-bunch (σe≃5fs) and long-bunch (σe≃20fs) operation modes of the Linac Coherent Light Source XFEL.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRA..118.7810R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRA..118.7810R"><span>Comparison between POES energetic <span class="hlt">electron</span> precipitation observations and riometer absorptions: Implications for determining true precipitation <span class="hlt">fluxes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodger, Craig J.; Kavanagh, Andrew J.; Clilverd, Mark A.; Marple, Steve R.</p> <p>2013-12-01</p> <p><span class="hlt">electron</span> precipitation (EEP) impacts the chemistry of the middle atmosphere with growing evidence of coupling to surface temperatures at high latitudes. To better understand this link, it is essential to have realistic observations to properly characterize precipitation and which can be incorporated into chemistry-climate models. The Polar-orbiting Operational Environmental Satellite (POES) detectors measure precipitating particles but only integral <span class="hlt">fluxes</span> and only in a fraction of the bounce loss cone. Ground-based riometers respond to precipitation from the whole bounce loss cone; they measure the cosmic radio noise absorption (CNA), a qualitative proxy with scant direct information on the energy <span class="hlt">flux</span> of EEP. POES observations should have a direct relationship with ΔCNA and comparing the two will clarify their utility in studies of atmospheric change. We determined ionospheric changes produced by the EEP measured by the POES spacecraft in ~250 overpasses of an imaging riometer in northern Finland. The ΔCNA modeled from the POES data is 10-15 times less than the observed ΔCNA when the >30 keV <span class="hlt">flux</span> is reported as <106 cm-2 s-1 sr-1. Above this level, there is relatively good agreement between the space-based and ground-based measurements. The discrepancy occurs mostly during periods of low geomagnetic activity, and we contend that weak diffusion is dominating the pitch angle scattering into the bounce loss cone at these times. A correction to the calculation using measurements of the trapped <span class="hlt">flux</span> considerably reduces the discrepancy and provides further support to our hypothesis that weak diffusion leads to underestimates of the EEP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5739214','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5739214"><span>Comparison of precipitating <span class="hlt">electron</span> energy <span class="hlt">flux</span> on March 22, 1979 with an empirical model: CDAW-6</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Simons S.L. Jr.; Reiff, P.H.; Spiro, R.W.; Hardy, D.A.; Kroehl, H.W.</p> <p>1985-03-01</p> <p>Data recorded by Defense Meterological Satellite Program, TIROS and P-78-1 satellites for the CDAW 6 event on March 22, 1979, have been compared with a statistical model of precipitating <span class="hlt">electron</span> <span class="hlt">fluxes</span>. Comparisons have been made on both an orbit-by-orbit basis and on a global basis by sorting and binning the data by AE index, invariant latitude and magnetic local time in a manner similar to which the model was generated. We conclude that the model <span class="hlt">flux</span> agrees with the data to within a factor of two, although small features and the exact locations of features are not consistently reproduced. In addition, the latitude of highest <span class="hlt">electron</span> precipitation usually occurs about 3/sup 0/ more pole-ward in the model than in the data. We attribute this discrepancy to ring current inflation of the storm time magnetosphere (as evidenced by negative Dst's). We suggest that a similar empirical model based on AL instead of AE and including some indicator of the history of the event would provide an even better comparison. Alternatively, in situ data such as electrojet location should be used routinely to normalize the latitude of the auroral precipitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810017461&hterms=energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D90%26Ntt%3Denergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810017461&hterms=energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D90%26Ntt%3Denergy"><span>A satellite investigation of energy <span class="hlt">flux</span> and inferred potential drop in auroral <span class="hlt">electron</span> energy spectra</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Meniett, J. D.; Burch, J. L.</p> <p>1981-01-01</p> <p>Because predicted relationship (epsilon directly varies with V squared) between auroral <span class="hlt">electron</span> energy <span class="hlt">flux</span> (epsilon) and the inferred acceleration potential drop (V) for accelerated Maxwellian distributions was favorably tested by other using sounding rocket data for the limiting case of eVE 1 (where Ec is the characteristic energy of the accelerated Maxwellian distribution) and for a single inverted-V observed by the Injun 5 satellite, data from Atmosphere D were used to extend these studies over the range .2 eV/Ec 5 and for a wide range of latitudes and local times on both the nightside and the dayside. Results show good agreement with the full accelerated Maxwellian model. An analytical approximation to the <span class="hlt">electron</span> energy <span class="hlt">flux</span> was derived which better describes the data over the range .2 eV/Ec approximated 3. Analyses of individual energy spectra at small and large pitch angles through well-defined inverted-V structures suggest that the altitude of the inferred potential drop maximizes near the center of the inverted-V's.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRA..117.4306G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRA..117.4306G"><span>Computing uncertainties in ionosphere-airglow models: I. <span class="hlt">Electron</span> <span class="hlt">flux</span> and species production uncertainties for Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gronoff, Guillaume; Simon Wedlund, Cyril; Mertens, Christopher J.; Lillis, Robert J.</p> <p>2012-04-01</p> <p>The ionization and excitation of atoms and molecules in the upper atmospheres of the Earth and planets are computed by a number of physical models. From these calculations, quantities measurable by dedicated satellite experiments such as airglow and <span class="hlt">electron</span> <span class="hlt">fluxes</span> can be derived. It is then possible to compare model and observation to derive more fundamental physical properties of the upper atmospheres, for example, the density as a function of altitude. To ensure the accuracy of these retrieval techniques, it is important to have an estimation of the uncertainty of these models and to have ways to account for these uncertainties. The complexity of kinetic models for computing the secondary production of excited state species (including ions) makes it a difficult evaluation, and studies usually neglect or underestimate it. We present here a Monte-Carlo approach to the computation of model uncertainties. As an example, we studied several aspects of the model uncertainties in the upper atmosphere of Mars, including the computed secondary <span class="hlt">electron</span> <span class="hlt">flux</span> and the production of the main ion species. Our simulations show the importance of improving solar <span class="hlt">flux</span> models, especially on the energy binning and on the photon impact cross sections, which are the main sources of uncertainties on the dayside. The risk of modifying cross sections on the basis of aeronomical observations is highlighted for the case of Mars, while accurate uncertainties are shown to be crucial for the interpretation of data from the particle detectors onboard Mars Global Surveyor. Finally, it shows the importance of AtMoCiad, a public database dedicated to the evaluation of aeronomy cross section uncertainties. A detailed study of the resulting emissions cross sections uncertainties is the focus of a forthcoming paper (Gronoff et al., 2012) in which the outputs discussed in the present paper are used to compute airglow uncertainty, and the overall result is compared with the data from the SPICAM UV</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...822...68A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...822...68A"><span>Fermi <span class="hlt">LAT</span> Stacking Analysis of Swift Localized GRBs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ackermann, M.; Ajello, M.; Anderson, B.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bhat, P. N.; Bissaldi, E.; Bonino, R.; Bottacini, E.; Brandt, T. J.; Bregeon, J.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caragiulo, M.; Caraveo, P. A.; Cecchi, C.; Charles, E.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Desiante, R.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Focke, W. B.; Franckowiak, A.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Giglietto, N.; Giordano, F.; Giroletti, M.; Godfrey, G.; Grenier, I. A.; Grove, J. E.; Guiriec, S.; Hewitt, J. W.; Hill, A. B.; Horan, D.; Jóhannesson, G.; Kocevski, D.; Kouveliotou, C.; Kuss, M.; Larsson, S.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Mayer, M.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Murgia, S.; Nemmen, R.; Nuss, E.; Ohno, M.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Racusin, J. L.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Schaal, M.; Schulz, A.; Sgrò, C.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Takahashi, H.; Thayer, J. B.; Tibaldo, L.; Tinivella, M.; Torres, D. F.; Tosti, G.; Troja, E.; Vianello, G.; von Kienlin, A.; Werner, M.; Wood, K. S.</p> <p>2016-05-01</p> <p>We perform a comprehensive stacking analysis of data collected by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) of γ-ray bursts (GRBs) localized by the Swift spacecraft, which were not detected by the <span class="hlt">LAT</span> but which fell within the instrument’s field of view at the time of trigger. We examine a total of 79 GRBs by comparing the observed counts over a range of time intervals to that expected from designated background orbits, as well as by using a joint likelihood technique to model the expected distribution of stacked counts. We find strong evidence for subthreshold emission at MeV to GeV energies using both techniques. This observed excess is detected during intervals that include and exceed the durations typically characterizing the prompt emission observed at keV energies and lasts at least 2700 s after the co-aligned burst trigger. By utilizing a novel cumulative likelihood analysis, we find that although a burst’s prompt γ-ray and afterglow X-ray <span class="hlt">flux</span> both correlate with the strength of the subthreshold emission, the X-ray afterglow <span class="hlt">flux</span> measured by Swift’s X-ray Telescope at 11 hr post trigger correlates far more significantly. Overall, the extended nature of the subthreshold emission and its connection to the burst’s afterglow brightness lend further support to the external forward shock origin of the late-time emission detected by the <span class="hlt">LAT</span>. These results suggest that the extended high-energy emission observed by the <span class="hlt">LAT</span> may be a relatively common feature but remains undetected in a majority of bursts owing to instrumental threshold effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355697-fermi-lat-stacking-analysis-swift-localized-grbs','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355697-fermi-lat-stacking-analysis-swift-localized-grbs"><span>Fermi <span class="hlt">LAT</span> Stacking Analysis of Swift Localized GRBs</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ackermann, M.; Ajello, M.; Anderson, B.; ...</p> <p>2016-05-05</p> <p>In this paper, we perform a comprehensive stacking analysis of data collected by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) of γ-ray bursts (GRBs) localized by the Swift spacecraft, which were not detected by the <span class="hlt">LAT</span> but which fell within the instrument's field of view at the time of trigger. We examine a total of 79 GRBs by comparing the observed counts over a range of time intervals to that expected from designated background orbits, as well as by using a joint likelihood technique to model the expected distribution of stacked counts. We find strong evidence for subthreshold emission at MeVmore » to GeV energies using both techniques. This observed excess is detected during intervals that include and exceed the durations typically characterizing the prompt emission observed at keV energies and lasts at least 2700 s after the co-aligned burst trigger. By utilizing a novel cumulative likelihood analysis, we find that although a burst's prompt γ-ray and afterglow X-ray <span class="hlt">flux</span> both correlate with the strength of the subthreshold emission, the X-ray afterglow <span class="hlt">flux</span> measured by Swift's X-ray Telescope at 11 hr post trigger correlates far more significantly. Overall, the extended nature of the subthreshold emission and its connection to the burst's afterglow brightness lend further support to the external forward shock origin of the late-time emission detected by the <span class="hlt">LAT</span>. Finally, these results suggest that the extended high-energy emission observed by the <span class="hlt">LAT</span> may be a relatively common feature but remains undetected in a majority of bursts owing to instrumental threshold effects.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SuScT..30d4002Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SuScT..30d4002Z"><span>A nanocryotron comparator can connect single-<span class="hlt">flux</span>-quantum circuits to conventional <span class="hlt">electronics</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Qing-Yuan; McCaughan, Adam N.; Dane, Andrew E.; Berggren, Karl K.; Ortlepp, Thomas</p> <p>2017-04-01</p> <p>Integration with conventional <span class="hlt">electronics</span> offers a straightforward and economical approach to upgrading existing superconducting technologies, such as scaling up superconducting detectors into large arrays and combining single <span class="hlt">flux</span> quantum (SFQ) digital circuits with semiconductor logic gates and memories. However, direct output signals from superconducting devices (e.g., Josephson junctions) are usually not compatible with the input requirements of conventional devices (e.g., transistors). Here, we demonstrate the use of a single three-terminal superconducting-nanowire device, called the nanocryotron (nTron), as a digital comparator to combine SFQ circuits with mature semiconductor circuits such as complementary metal oxide semiconductor (CMOS) circuits. Since SFQ circuits can digitize output signals from general superconducting devices and CMOS circuits can interface existing CMOS-compatible <span class="hlt">electronics</span>, our results demonstrate the feasibility of a general architecture that uses an nTron as an interface to realize a ‘super-hybrid’ system consisting of superconducting detectors, superconducting quantum <span class="hlt">electronics</span>, CMOS logic gates and memories, and other conventional <span class="hlt">electronics</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM31A2446S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM31A2446S"><span>Combined effects of ULF, VLF, and EMIC Waves, Substorms, and Solar Wind Parameters on Relativistic <span class="hlt">Electron</span> <span class="hlt">Flux</span>: Multiple Regression Analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simms, L. E.; Engebretson, M. J.; Rodger, C. J.; Gjerloev, J. W.; Lessard, M.; Clilverd, M. A.; Pilipenko, V.; Reeves, G. D.</p> <p>2016-12-01</p> <p>Relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> may be influenced by energy inputs from the solar wind (velocity, number density, and IMF Bz), substorm activity, source and seed <span class="hlt">electron</span> populations (tens of keV and hundreds of keV, respectively), as well as by the ULF, VLF, and EMIC waves triggered by these factors. As all these variables are intercorrelated, we use multiple regression analyses to determine which are most influential when other factors are controlled. For the years 2005-2011, we use daily averages of LANL geostationary orbit <span class="hlt">electron</span> data (three high energy channels, as well as source and seed <span class="hlt">electrons</span>), number of substorms per day from the SUPERMAG substorm list, a ULF index from ground magnetometers, lower band whistler mode chorus power (VLF) observed by the DEMETER satellite, and EMIC (< 1 Hz) wave data from the Halley ground station. The correlations found in the linear multiple regression support several hypotheses. ULF and VLF waves enhance the 1.8-3.5 MeV <span class="hlt">electron</span> <span class="hlt">flux</span> but their effect falls off (or becomes negative) on higher energy <span class="hlt">fluxes</span> (3.5-6.0 and 6.0-7.8 MeV). EMIC waves reduce high energy <span class="hlt">electron</span> <span class="hlt">flux</span> mainly in the highest energy channel (6.0-7.8 MeV); their effect on the lower 1.8-3.5 MeV channel is minimal. A higher number of substorms in a day also enhance relativistic <span class="hlt">electron</span> <span class="hlt">flux</span>, with more impact at higher energy channels. We explore the relations between these parameters using path analysis to determine the mechanisms driving wave power which subsequently impact <span class="hlt">flux</span> levels. We also assess the predictive ability of these models in forecasting <span class="hlt">flux</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990KosIs..28..623G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990KosIs..28..623G"><span>Mean <span class="hlt">fluxes</span> of <span class="hlt">electrons</span> and protons with energies of 1-20 keV on polar-satellite trajectories</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Getselev, I. V.; Gubar', Iu. I.; Kropotkin, A. P.; Mart'ianov, S. A.; Timofeev, G. A.</p> <p>1990-07-01</p> <p>It is pointed out that 1-20-keV <span class="hlt">electron</span> and proton <span class="hlt">fluxes</span> have a significant effect on spacecraft surface layers in space. Mean spectra of 1-20 keV <span class="hlt">electrons</span> and protons have been determined for polar-satellite trajectories at heights ranging from 500 to 1000 km for orbital inclinations of 50, 65, and 80-100 deg.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..93r4302M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..93r4302M"><span>Systematic <span class="hlt">electronic</span>-structure investigation of substitutional impurity diffusion and <span class="hlt">flux</span> coupling in bcc iron</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Messina, Luca; Nastar, Maylise; Sandberg, Nils; Olsson, Pär</p> <p>2016-05-01</p> <p>The diffusion properties of a wide range of impurities (transition metals and Al, Si, and P) in ferritic alloys are here investigated by means of a combined ab initio-atomic diffusion theory approach. The <span class="hlt">flux</span>-coupling mechanisms and the solute-diffusion coefficients are inferred from <span class="hlt">electronic</span>-structure calculations of solute-defect interactions and microscopic jump frequencies. All properties except the second-nearest-neighbor binding energy are found to have a characteristic bell shape as a function of the d -band filling for the 4 d and 5 d series, and an M shape for the 3 d row because of the out-of-trend behavior of Mn. The solute jump frequencies are governed by compressibility, which makes diffusion of large solutes faster, although this effect is partially compensated for by lower attempt frequencies and larger correlations with the vacancy. Diffusion coefficients are predicted in a wide temperature range, far below the experimentally accessible temperatures. In accordance with experiments, Co is found to be a slow diffuser in iron, and the same behavior is predicted for Re, Os, and Ir impurities. Finally, <span class="hlt">flux</span>-coupling phenomena depend on the iron jump frequencies next to a solute atom, which are mainly controlled by similar <span class="hlt">electronic</span> interactions to those determining the binding energies. Vacancy drag and solute enrichment at sinks systematically arise below a solute-dependent temperature threshold, directly correlated with the <span class="hlt">electronic</span>-level interactions at the equilibrium and the saddle-point states. Early transition metals with repulsive second-nearest-neighbor interactions also diffuse via vacancy drag, although they show a lower temperature threshold than the late metals. This confirms that drag is the most common solute-vacancy coupling mechanism in iron at low temperatures, and this is likely to be confirmed as well for impurity diffusion in other transition metals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760061664&hterms=min&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmin','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760061664&hterms=min&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmin"><span>The 2- to 12-min quasi-periodic variation of 50- to 1000-keV trapped <span class="hlt">electron</span> <span class="hlt">fluxes</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lin, C. S.; Parks, G. K.; Winckler, J. R.</p> <p>1976-01-01</p> <p>It was previously shown that trapped <span class="hlt">electron</span> <span class="hlt">fluxes</span> of energies in the range from 50 keV to 1 MeV observed in the afternoon magnetosphere during substorms frequently undergo periodic variations. High-resolution <span class="hlt">electron</span> spectrometer data indicate that these <span class="hlt">electron</span> variations are periodic in the range of about 2-12 min, correlated with magnetic field variations, organized by the local magnetic field, and dependent on pitch angle. The observations suggest that the <span class="hlt">electron</span> variations are adiabatic. The study derives quantitative adiabatic expressions of particle <span class="hlt">flux</span> variations in a model geomagnetic field perturbation to show that the observational features are consistent with effects arising from adiabatic modulation of trapped particle <span class="hlt">fluxes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ascl.soft11027V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ascl.soft11027V"><span>BKGE: Fermi-<span class="hlt">LAT</span> Background Estimator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vasileiou, Vlasios</p> <p>2014-11-01</p> <p>The Fermi-<span class="hlt">LAT</span> Background Estimator (BKGE) is a publicly available open-source tool that can estimate the expected background of the Fermi-<span class="hlt">LAT</span> for any observational conguration and duration. It produces results in the form of text files, ROOT files, gtlike source-model files (for <span class="hlt">LAT</span> maximum likelihood analyses), and PHA I/II FITS files (for RMFit/XSpec spectral fitting analyses). Its core is written in C++ and its user interface in Python.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PDU....11....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PDU....11....1C"><span>Confronting recent AMS-02 positron fraction and Fermi-<span class="hlt">LAT</span> extragalactic γ-ray background measurements with gravitino dark matter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carquín, Edson; Díaz, Marco A.; Gómez-Vargas, Germán A.; Panes, Boris; Viaux, Nicolás</p> <p>2016-03-01</p> <p>Recent positron <span class="hlt">flux</span> fraction measurements in cosmic-rays (CR) made by the AMS-02 detector confirm and extend the evidence on the existence of a new (yet unknown) source of high energy <span class="hlt">electrons</span> and positrons. We test the gravitino dark matter of bilinear R-parity violating supersymmetric models as this <span class="hlt">electrons</span>/positrons source. Being a long lived weak-interacting and spin 3/2 particle, it offers several particularities which makes it an attractive dark matter candidate. We compute the <span class="hlt">electron</span>, positron and γ-ray <span class="hlt">fluxes</span> produced by each gravitino decay channel as it would be detected at the Earth's position. Combining the <span class="hlt">flux</span> from the different decay modes we are able to reproduce AMS-02 measurements of the positron fraction, as well as the <span class="hlt">electron</span> and positron <span class="hlt">fluxes</span>, with a gravitino dark matter mass in the range 1-3 TeV and lifetime of ˜1.0-0.7×1026 s. The high statistics measurement of <span class="hlt">electron</span> and positron <span class="hlt">fluxes</span>, and the flattening in the behaviour of the positron fraction recently found by AMS-02 allow us to determine that the preferred gravitino decaying mode by the fit is W±τ∓, unlike previous analyses. Then we study the viability of these scenarios through their implication in γ-ray observations. For this we use the Extragalactic γ-ray Background recently reported by the Fermi-<span class="hlt">LAT</span> Collaboration and a state-of-the-art model of its known contributors. Based on the γ-ray analysis we exclude the gravitino parameter space which provides an acceptable explanation of the AMS-02 data. Therefore, we conclude that the gravitino of bilinear R-parity violating models is ruled out as the unique primary source of <span class="hlt">electrons</span> and positrons needed to explain the rise in the positron fraction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AAS...21344601C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AAS...21344601C"><span>Optical Observations Of Fermi <span class="hlt">LAT</span> Monitored Blazars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cook, Kyle; Carini, M. T.</p> <p>2009-01-01</p> <p>For the past 8 years the Bell Observatory at Western Kentucky University has been conducting R band monitoring of the variability of approximately 50 Blazars. A subset of these objects are being routinely observed with the <span class="hlt">LAT</span> instrument on-board the Fermi Space Telescope. Adding the Robotically Controlled Telescope (RCT) at Kitt Peak National Observatory and observations with the AZT-11 telescope at the Crimean Astrophysical Observatory (CRAO), we are intensively monitoring the Blazars on the <span class="hlt">Lat</span> monitoring list. We present the results of our long term monitoring of the <span class="hlt">LAT</span> monitored Blazars, as well as the recent contemporaneous optical R band observations we have obtained of the <span class="hlt">LAT</span> Blazars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PASJ...64..100Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PASJ...64..100Y"><span>Constraining Intergalactic Magnetic Field with Fermi-<span class="hlt">LAT</span> Observation of Cascade Radiation for TeV Blazars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Jianping; Wang, Jiancheng; Yang, Jianrong</p> <p>2012-10-01</p> <p>The problem concerning the origin of the Intergalactic Magnetic Field (IGMF) is one of the long-standing problems of astrophysics and cosmology, and direct measurements are difficult. TeV photons emitted by TeV blazars produce <span class="hlt">electron</span>-positron pairs because of interactions with the extragalactic background light (EBL). These pairs emit secondary cascade gamma-rays via Inverse Compton scattering of the cosmic microwave background (CMB) photons. In this process, the trajectories of the pairs are deviated by the IGMF, and the cascade gamma-ray emission appears as extended emission around TeV source. We used the EBL, synchrotron self-Compton (SSC) model and the observed limits on Lorentz factor of <span class="hlt">electron</span>-positron pairs to calculate the cascade-radiation spectrum, and then to fit the observed GeV to TeV and multi-waveband spectra of TeV blazars to constrain the IGMF. We obtained the GeV energy spectra of three TeV blazars by analyzing the Fermi-<span class="hlt">LAT</span> data of the past ˜ 3 yr. The <span class="hlt">flux</span> upper limits of Fermi-<span class="hlt">LAT</span> in the 90% significant level of 1ES 0229+200 suggests that the IGMF is stronger than 2 × 10-18 G for an engine time of TeV activity with three years. The relationships between the deduced lower limits of IGMF and various engine times for 1ES 0229+200 and 1ES 0347-121 are presented by us.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRA..119.6386W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRA..119.6386W"><span>The effects and correction of the geometric factor for the POES/MEPED <span class="hlt">electron</span> <span class="hlt">flux</span> instrument using a multisatellite comparison</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Whittaker, Ian C.; Rodger, Craig J.; Clilverd, Mark A.; Sauvaud, Jean-André</p> <p>2014-08-01</p> <p>Measurements from the Polar-Orbiting Environmental Satellite (POES) Medium Energy Proton and <span class="hlt">Electron</span> Detector (MEPED) instrument are widely used in studies into radiation belt dynamics and atmospheric coupling. However, this instrument has been shown to have a complex energy-dependent response to incident particle <span class="hlt">fluxes</span>, with the additional possibility of low-energy protons contaminating the <span class="hlt">electron</span> <span class="hlt">fluxes</span>. We test the recent Monte Carlo theoretical simulation of the instrument by comparing the responses against observations from an independent experimental data set. Our study examines the reported geometric factors for the MEPED <span class="hlt">electron</span> <span class="hlt">flux</span> instrument against the high-energy resolution Instrument for Detecting Particles (IDPs) on the Detection of Electromagnetic Emissions Transmitted from Earthquake Regions satellite when they are located at similar locations and times, thereby viewing the same quasi-trapped population of <span class="hlt">electrons</span>. We find that the new Monte Carlo-produced geometric factors accurately describe the response of the POES MEPED instrument. We go on to develop a set of equations such that integral <span class="hlt">electron</span> <span class="hlt">fluxes</span> of a higher accuracy are obtained from the existing MEPED observations. These new MEPED integral <span class="hlt">fluxes</span> correlated very well with those from the IDP instrument (>99.9% confidence level). As part of this study we have also tested a commonly used algorithm for removing proton contamination from MEPED instrument observations. We show that the algorithm is effective, providing confirmation that previous work using this correction method is valid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3068929','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3068929"><span>Reactive Oxygen Species Production by Forward and Reverse <span class="hlt">Electron</span> <span class="hlt">Fluxes</span> in the Mitochondrial Respiratory Chain</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Selivanov, Vitaly A.; Votyakova, Tatyana V.; Pivtoraiko, Violetta N.; Zeak, Jennifer; Sukhomlin, Tatiana; Trucco, Massimo; Roca, Josep; Cascante, Marta</p> <p>2011-01-01</p> <p>Reactive oxygen species (ROS) produced in the mitochondrial respiratory chain (RC) are primary signals that modulate cellular adaptation to environment, and are also destructive factors that damage cells under the conditions of hypoxia/reoxygenation relevant for various systemic diseases or transplantation. The important role of ROS in cell survival requires detailed investigation of mechanism and determinants of ROS production. To perform such an investigation we extended our rule-based model of complex III in order to account for <span class="hlt">electron</span> transport in the whole RC coupled to proton translocation, transmembrane electrochemical potential generation, TCA cycle reactions, and substrate transport to mitochondria. It fits respiratory <span class="hlt">electron</span> <span class="hlt">fluxes</span> measured in rat brain mitochondria fueled by succinate or pyruvate and malate, and the dynamics of NAD+ reduction by reverse <span class="hlt">electron</span> transport from succinate through complex I. The fitting of measured characteristics gave an insight into the mechanism of underlying processes governing the formation of free radicals that can transfer an unpaired <span class="hlt">electron</span> to oxygen-producing superoxide and thus can initiate the generation of ROS. Our analysis revealed an association of ROS production with levels of specific radicals of individual <span class="hlt">electron</span> transporters and their combinations in species of complexes I and III. It was found that the phenomenon of bistability, revealed previously as a property of complex III, remains valid for the whole RC. The conditions for switching to a state with a high content of free radicals in complex III were predicted based on theoretical analysis and were confirmed experimentally. These findings provide a new insight into the mechanisms of ROS production in RC. PMID:21483483</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4375552','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4375552"><span>A Well-Balanced Preexisting Equilibrium Governs <span class="hlt">Electron</span> <span class="hlt">Flux</span> Efficiency of a Multidomain Diflavin Reductase</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Frances, Oriane; Fatemi, Fataneh; Pompon, Denis; Guittet, Eric; Sizun, Christina; Pérez, Javier; Lescop, Ewen; Truan, Gilles</p> <p>2015-01-01</p> <p>Diflavin reductases are bidomain <span class="hlt">electron</span> transfer proteins in which structural reorientation is necessary to account for the various intramolecular and intermolecular <span class="hlt">electron</span> transfer steps. Using small-angle x-ray scattering and nuclear magnetic resonance data, we describe the conformational free-energy landscape of the NADPH-cytochrome P450 reductase (CPR), a typical bidomain redox enzyme composed of two covalently-bound flavin domains, under various experimental conditions. The CPR enzyme exists in a salt- and pH-dependent rapid equilibrium between a previously described rigid, locked state and a newly characterized, highly flexible, unlocked state. We further establish that maximal <span class="hlt">electron</span> <span class="hlt">flux</span> through CPR is conditioned by adjustable stability of the locked-state domain interface under resting conditions. This is rationalized by a kinetic scheme coupling rapid conformational sampling and slow chemical reaction rates. Regulated domain interface stability associated with fast stochastic domain contacts during the catalytic cycle thus provides, to our knowledge, a new paradigm for improving our understanding of multidomain enzyme function. PMID:25809265</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhD...49WLT01L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhD...49WLT01L"><span><span class="hlt">Electron</span> heating and particle <span class="hlt">fluxes</span> in dual frequency atmospheric-pressure helium capacitive discharge</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Dingxin; Yang, Aijun; Wang, Xiaohua; Chen, Chen; Rong, Mingzhe; Kong, Michael G.</p> <p>2016-12-01</p> <p>In this letter, a 1D fluid model has been used to study the <span class="hlt">electron</span> heating and particle transport in dual frequency atmospheric-pressure helium capacitive discharge with a high-frequency (HF) voltage of 10 MHz and a low-frequency (LF) voltage of 1 MHz. The electric field is decoupled to three components: the HF, the LF and the direct current (DC) ones, and they have much different effects on the plasmas. The eletrons in plasma bulk are mainly heated by the HF electric field, while in plasma sheath they are heated and cooled by the LF and DC electric fields, respectively. With a fixed total input power, the increase of LF power leads to great enhancement of the electrode <span class="hlt">fluxes</span> of <span class="hlt">electrons</span> and ions, especially for the energetic <span class="hlt">electrons</span> of T e  >  2 eV, because more power is dissipated in the vicinity of electrodes and the inelastic collision is more pronounced. Therefore, the particle transport on the treated sample can be greatly enhanced without additional gas heating in dual frequency plasmas, which meets the application requirements more compared to the single frequency plasmas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1912799A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1912799A"><span>New homogeneous composite of energetic <span class="hlt">electron</span> <span class="hlt">fluxes</span> from NOAA/POES satellites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Asikainen, Timo; Ruopsa, Miro</p> <p>2017-04-01</p> <p>One of the most widely popular datasets of energetic particles used in, e.g., long-term radiation belt studies and in atmospheric/climate studies is perhaps the NOAA/POES (Polar Orbiting Environmental Satellites) dataset, which is unique in its length extending nearly continuously from 1979 to present. However, it has been long recognized that the energetic particle measurements by the MEPED instrument (Medium Energy Proton and <span class="hlt">Electron</span> Detector) onboard the POES satellites has numerous instrumental problems, which have made quantitative estimates of energetic particle <span class="hlt">fluxes</span> somewhat difficult. In the recent years a lot of effort has been put in understanding and correcting these instrumental deficiencies, and as a result we have produced a dataset, which corrects instrumental degradation, <span class="hlt">electronic</span> noise and various sensitivity and contamination issues. However, here we show that there are also other remaining factors, not related to instrument construction, which still cause the 37 year POES dataset to be significantly inhomogeneous. One inhomogeneity is caused by the drift in the orientation of the satellite orbital planes over long periods of time. Another, even more serious issue, is the difference in the orientation of the particle telescopes between the satellites flown before mid-1998 (SEM-1 era) and after that (SEM-2 era). Here we discuss these effects and how the data can be corrected for them. We present a new homogenized composite data series, which yields the latitudinal distribution of energetic <span class="hlt">electrons</span> from 1979 to present with daily time resolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..DPPYO4008Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..DPPYO4008Y"><span>Statistics of field-aligned intermittent <span class="hlt">electron</span> <span class="hlt">flux</span> in a linear ECR plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yoshimura, Shinji; Terasaka, Kenichiro; Aramaki, Mitsutoshi; Tanaka, Masayoshi Y.</p> <p>2012-10-01</p> <p>Spontaneous emission of field-aligned intermittent high-energy <span class="hlt">electron</span> <span class="hlt">flux</span> has been observed in a linear <span class="hlt">electron</span>-cyclotron-resonance (ECR) plasma produced in the HYPER-I device (NIFS, Japan). We utilized the temporal variation of probe's floating potential due to <span class="hlt">electron</span> influx as an index of the intermittent events. Time series of the floating potential fluctuation have been analyzed statistically. The probability density function (PDF) exhibits a non-Gaussian distribution with a long tail in the negative amplitude side, indicating that the signal is dominated by large amplitude negative spikes. The frequency distribution of waiting time, which is defined by the time interval between two consecutive spikes, is well fitted by an exponential distribution, implying a probable connection to the stationary Poisson process. Although a power-law dependence is found in the duration distribution, its relation to the self-organized criticality has not been clear. The effect of ion species on the statistics above will also be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25809265','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25809265"><span>A well-balanced preexisting equilibrium governs <span class="hlt">electron</span> <span class="hlt">flux</span> efficiency of a multidomain diflavin reductase.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Frances, Oriane; Fatemi, Fataneh; Pompon, Denis; Guittet, Eric; Sizun, Christina; Pérez, Javier; Lescop, Ewen; Truan, Gilles</p> <p>2015-03-24</p> <p>Diflavin reductases are bidomain <span class="hlt">electron</span> transfer proteins in which structural reorientation is necessary to account for the various intramolecular and intermolecular <span class="hlt">electron</span> transfer steps. Using small-angle x-ray scattering and nuclear magnetic resonance data, we describe the conformational free-energy landscape of the NADPH-cytochrome P450 reductase (CPR), a typical bidomain redox enzyme composed of two covalently-bound flavin domains, under various experimental conditions. The CPR enzyme exists in a salt- and pH-dependent rapid equilibrium between a previously described rigid, locked state and a newly characterized, highly flexible, unlocked state. We further establish that maximal <span class="hlt">electron</span> <span class="hlt">flux</span> through CPR is conditioned by adjustable stability of the locked-state domain interface under resting conditions. This is rationalized by a kinetic scheme coupling rapid conformational sampling and slow chemical reaction rates. Regulated domain interface stability associated with fast stochastic domain contacts during the catalytic cycle thus provides, to our knowledge, a new paradigm for improving our understanding of multidomain enzyme function.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002394&hterms=cluster&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcluster','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002394&hterms=cluster&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcluster"><span>Van Allen Probes, THEMIS, GOES, and Cluster Observations of EMIC Waves, ULF Pulsations, and an <span class="hlt">Electron</span> <span class="hlt">Flux</span> Dropout</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sigsbee, K.; Kletzing, C. A.; Smith, C. W.; Macdowall, R.; Spence, H.; Reeves, G.; Blake, J. B.; Baker, D. N.; Green, J. C.; Singer, H. J.; Carr, C.; Santolík, O.</p> <p>2016-01-01</p> <p>We examined an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout during the 12-14 November 2012 geomagnetic storm using observations from seven spacecraft: the two Van Allen Probes, Time History of Events and Macroscale Interactions during Substorms (THEMIS)-A (P5), Cluster 2, and Geostationary Operational Environmental Satellites (GOES) 13, 14, and 15. The <span class="hlt">electron</span> <span class="hlt">fluxes</span> for energies greater than 2.0 MeV observed by GOES 13, 14, and 15 at geosynchronous orbit and by the Van Allen Probes remained at or near instrumental background levels for more than 24 h from 12 to 14 November. For energies of 0.8 MeV, the GOES satellites observed two shorter intervals of reduced <span class="hlt">electron</span> <span class="hlt">fluxes</span>. The first interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 12-13 November was associated with an interplanetary shock and a sudden impulse. Cluster, THEMIS, and GOES observed intense He+ electromagnetic ion cyclotron (EMIC) waves from just inside geosynchronous orbit out to the magnetopause across the dayside to the dusk flank. The second interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 13-14 November was associated with a solar sector boundary crossing and development of a geomagnetic storm with Dst<100 nT. At the start of the recovery phase, both the 0.8 and 2.0 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> finally returned to near prestorm values, possibly in response to strong ultralow frequency (ULF) waves observed by the Van Allen Probes near dawn. A combination of adiabatic effects, losses to the magnetopause, scattering by EMIC waves, and acceleration by ULF waves can explain the observed <span class="hlt">electron</span> behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.1990S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.1990S"><span>Van Allen Probes, THEMIS, GOES, and Cluster observations of EMIC waves, ULF pulsations, and an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sigsbee, K.; Kletzing, C. A.; Smith, C. W.; MacDowall, R.; Spence, H.; Reeves, G.; Blake, J. B.; Baker, D. N.; Green, J. C.; Singer, H. J.; Carr, C.; Santolík, O.</p> <p>2016-03-01</p> <p>We examined an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout during the 12-14 November 2012 geomagnetic storm using observations from seven spacecraft: the two Van Allen Probes, Time History of Events and Macroscale Interactions during Substorms (THEMIS)-A (P5), Cluster 2, and Geostationary Operational Environmental Satellites (GOES) 13, 14, and 15. The <span class="hlt">electron</span> <span class="hlt">fluxes</span> for energies greater than 2.0 MeV observed by GOES 13, 14, and 15 at geosynchronous orbit and by the Van Allen Probes remained at or near instrumental background levels for more than 24 h from 12 to 14 November. For energies of 0.8 MeV, the GOES satellites observed two shorter intervals of reduced <span class="hlt">electron</span> <span class="hlt">fluxes</span>. The first interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 12-13 November was associated with an interplanetary shock and a sudden impulse. Cluster, THEMIS, and GOES observed intense He+ electromagnetic ion cyclotron (EMIC) waves from just inside geosynchronous orbit out to the magnetopause across the dayside to the dusk flank. The second interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 13-14 November was associated with a solar sector boundary crossing and development of a geomagnetic storm with Dst < -100 nT. At the start of the recovery phase, both the 0.8 and 2.0 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> finally returned to near prestorm values, possibly in response to strong ultralow frequency (ULF) waves observed by the Van Allen Probes near dawn. A combination of adiabatic effects, losses to the magnetopause, scattering by EMIC waves, and acceleration by ULF waves can explain the observed <span class="hlt">electron</span> behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002394&hterms=allen&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dallen','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002394&hterms=allen&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dallen"><span>Van Allen Probes, THEMIS, GOES, and Cluster Observations of EMIC Waves, ULF Pulsations, and an <span class="hlt">Electron</span> <span class="hlt">Flux</span> Dropout</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sigsbee, K.; Kletzing, C. A.; Smith, C. W.; Macdowall, R.; Spence, H.; Reeves, G.; Blake, J. B.; Baker, D. N.; Green, J. C.; Singer, H. J.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170002394'); toggleEditAbsImage('author_20170002394_show'); toggleEditAbsImage('author_20170002394_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170002394_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170002394_hide"></p> <p>2016-01-01</p> <p>We examined an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout during the 12-14 November 2012 geomagnetic storm using observations from seven spacecraft: the two Van Allen Probes, Time History of Events and Macroscale Interactions during Substorms (THEMIS)-A (P5), Cluster 2, and Geostationary Operational Environmental Satellites (GOES) 13, 14, and 15. The <span class="hlt">electron</span> <span class="hlt">fluxes</span> for energies greater than 2.0 MeV observed by GOES 13, 14, and 15 at geosynchronous orbit and by the Van Allen Probes remained at or near instrumental background levels for more than 24 h from 12 to 14 November. For energies of 0.8 MeV, the GOES satellites observed two shorter intervals of reduced <span class="hlt">electron</span> <span class="hlt">fluxes</span>. The first interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 12-13 November was associated with an interplanetary shock and a sudden impulse. Cluster, THEMIS, and GOES observed intense He+ electromagnetic ion cyclotron (EMIC) waves from just inside geosynchronous orbit out to the magnetopause across the dayside to the dusk flank. The second interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 13-14 November was associated with a solar sector boundary crossing and development of a geomagnetic storm with Dst<100 nT. At the start of the recovery phase, both the 0.8 and 2.0 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> finally returned to near prestorm values, possibly in response to strong ultralow frequency (ULF) waves observed by the Van Allen Probes near dawn. A combination of adiabatic effects, losses to the magnetopause, scattering by EMIC waves, and acceleration by ULF waves can explain the observed <span class="hlt">electron</span> behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1258442','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1258442"><span>Van Allen Probes, THEMIS, GOES, and cluster observations of EMIC waves, ULF pulsations, and an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sigsbee, K.; Kletzing, C. A.; Smith, C. W.; MacDowall, R.; Spence, H.; Reeves, G.; Blake, J. B.; Baker, D. N.; Green, J. C.; Singer, H. J.; Carr, C.; Santolik, O.</p> <p>2016-03-04</p> <p>We examined an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout during the 12–14 November 2012 geomagnetic storm using observations from seven spacecraft: the two Van Allen Probes, Time History of Events and Macroscale Interactions during Substorms (THEMIS)-A (P5), Cluster 2, and Geostationary Operational Environmental Satellites (GOES) 13, 14, and 15. The <span class="hlt">electron</span> <span class="hlt">fluxes</span> for energies greater than 2.0 MeV observed by GOES 13, 14, and 15 at geosynchronous orbit and by the Van Allen Probes remained at or near instrumental background levels for more than 24 h from 12 to 14 November. For energies of 0.8 MeV, the GOES satellites observed two shorter intervals of reduced <span class="hlt">electron</span> <span class="hlt">fluxes</span>. The first interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 12–13 November was associated with an interplanetary shock and a sudden impulse. Cluster, THEMIS, and GOES observed intense He<sup>+</sup> electromagnetic ion cyclotron (EMIC) waves from just inside geosynchronous orbit out to the magnetopause across the dayside to the dusk flank. The second interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 13–14 November was associated with a solar sector boundary crossing and development of a geomagnetic storm with Dst <–100 nT. At the start of the recovery phase, both the 0.8 and 2.0 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> finally returned to near prestorm values, possibly in response to strong ultralow frequency (ULF) waves observed by the Van Allen Probes near dawn. A combination of adiabatic effects, losses to the magnetopause, scattering by EMIC waves, and acceleration by ULF waves can explain the observed <span class="hlt">electron</span> behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1258442-van-allen-probes-themis-goes-cluster-observations-emic-waves-ulf-pulsations-electron-flux-dropout','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1258442-van-allen-probes-themis-goes-cluster-observations-emic-waves-ulf-pulsations-electron-flux-dropout"><span>Van Allen Probes, THEMIS, GOES, and cluster observations of EMIC waves, ULF pulsations, and an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Sigsbee, K.; Kletzing, C. A.; Smith, C. W.; ...</p> <p>2016-03-04</p> <p>We examined an <span class="hlt">electron</span> <span class="hlt">flux</span> dropout during the 12–14 November 2012 geomagnetic storm using observations from seven spacecraft: the two Van Allen Probes, Time History of Events and Macroscale Interactions during Substorms (THEMIS)-A (P5), Cluster 2, and Geostationary Operational Environmental Satellites (GOES) 13, 14, and 15. The <span class="hlt">electron</span> <span class="hlt">fluxes</span> for energies greater than 2.0 MeV observed by GOES 13, 14, and 15 at geosynchronous orbit and by the Van Allen Probes remained at or near instrumental background levels for more than 24 h from 12 to 14 November. For energies of 0.8 MeV, the GOES satellites observed two shorter intervalsmore » of reduced <span class="hlt">electron</span> <span class="hlt">fluxes</span>. The first interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 12–13 November was associated with an interplanetary shock and a sudden impulse. Cluster, THEMIS, and GOES observed intense He+ electromagnetic ion cyclotron (EMIC) waves from just inside geosynchronous orbit out to the magnetopause across the dayside to the dusk flank. The second interval of reduced 0.8 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> on 13–14 November was associated with a solar sector boundary crossing and development of a geomagnetic storm with Dst <–100 nT. At the start of the recovery phase, both the 0.8 and 2.0 MeV <span class="hlt">electron</span> <span class="hlt">fluxes</span> finally returned to near prestorm values, possibly in response to strong ultralow frequency (ULF) waves observed by the Van Allen Probes near dawn. A combination of adiabatic effects, losses to the magnetopause, scattering by EMIC waves, and acceleration by ULF waves can explain the observed <span class="hlt">electron</span> behavior.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22365532','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22365532"><span><span class="hlt">ELECTRON</span> HEAT <span class="hlt">FLUX</span> IN THE SOLAR WIND: ARE WE OBSERVING THE COLLISIONAL LIMIT IN THE 1 AU DATA?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Landi, S.; Matteini, L.; Pantellini, F.</p> <p>2014-07-20</p> <p>Using statistically significant data at 1 AU, it has recently been shown (Bale et al.) that in the solar wind, when the Knudsen number K {sub T} (the ratio between the <span class="hlt">electron</span> mean free path and the <span class="hlt">electron</span> temperature scale height) drops below about 0.3, the <span class="hlt">electron</span> heat <span class="hlt">flux</span> q intensity rapidly approaches the classical collisional Spitzer-Härm limit. Using a fully kinetic model including the effect of Coulomb collisions and the expansion of the solar wind with heliocentric distance, we observe that the heat <span class="hlt">flux</span> strength does indeed approach the collisional value for Knudsen numbers smaller than about 0.3 in very good agreement with the observations. However, closer inspection of the heat <span class="hlt">flux</span> properties, such as its variation with the heliocentric distance and its dependence on the plasma parameters, shows that for Knudsen numbers between 0.02 and 0.3 the heat <span class="hlt">flux</span> is not conveniently described by the Spitzer-Härm formula. We conclude that even though observations at 1 AU seem to indicate that the <span class="hlt">electron</span> heat <span class="hlt">flux</span> intensity approaches the collisional limit when the Knudsen drops below ∼0.3, the collisional limit is not a generally valid closure for a Knudsen larger than 0.01. Moreover, the good agreement between the heat <span class="hlt">flux</span> from our model and the heat <span class="hlt">flux</span> from solar wind measurements in the high-Knudsen number regime seems to indicate that the heat <span class="hlt">flux</span> at 1 AU is not constrained by electromagnetic instabilities as both wave-particle and wave-wave interactions are neglected in our calculations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770026467','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770026467"><span>Surface charge kinetics near metal-dielectric interfaces exposed to kilovolt <span class="hlt">electron</span> <span class="hlt">flux</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Robinson, J. W.</p> <p>1977-01-01</p> <p>Interfaces between dielectric films and grounded metallic boundaries were exposed, in vacuum, to monoenergic <span class="hlt">electron</span> <span class="hlt">fluxes</span> having energies up to 22 keV. Two principal concerns were the measuring of the charge distributions on dielectrics and the determining of causes of flashovers, events where dielectric surface charges abruptly transfer to the metallic structures. Surface charges are perturbed within 10 mm of interfaces. Perturbations are relatively small except within about 3 mm of the interface. The probability of flashover was found to be related to microscopic imperfections in the interfaces. As flashovers occur in an exposed metal substrate, points become burned into the dielectric along the slit. As these points develop, the probability of flashover increases greatly. An interface which is highly immune to flashover was formed by covering a dielectric film with a 1.5-mm-thick aperture plate which exposes the film through a machined opening.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMSH11B1664L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMSH11B1664L"><span>STEREO SWEA Observations of Solar Wind Halo <span class="hlt">Electron</span> Anomalous Heat <span class="hlt">Fluxes</span> and their Organization by Solar Wind Structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luhmann, J. G.; Ellenburg, M. A.; Lee, C. O.; Schroeder, P. C.; Opitz, A.; Penou, E.; Lavraud, B.; Sauvaud, J. A.; Jian, L.; Russell, C. T.; Simunac, K. D.; Galvin, A. B.</p> <p>2010-12-01</p> <p>STEREO SWEA (Solar Wind <span class="hlt">Electron</span> Analyzer) provides the opportunity to observe solar wind halo <span class="hlt">electron</span> heat <span class="hlt">fluxes</span> and strahl over 4pi steradians at locations free of Earth bow shock contamination. We have analyzed these measurements together with the magnetic field and plasma parameters to determine their organization with solar wind stream structure during the period between early 2007 and late 2009. This period is characterized by a very low level of solar activity and thus presents an opportunity to diagnose the anomalous features, determining their location and character. This includes heat <span class="hlt">fluxes</span> that appear to be traveling back toward the Sun, possibly indicating folded interplanetary field lines, interplanetary field loops which may be part of ICMEs, or sources of suprathermal <span class="hlt">electrons</span> at shocks beyond 1 AU. Our results give a broad view of the issues related to using heat <span class="hlt">fluxes</span> to interpret interplanetary field topology, even with the benefit of 4pi observations and two spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NucFu..57b2010A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NucFu..57b2010A"><span>Fast measurements of the <span class="hlt">electron</span> temperature and parallel heat <span class="hlt">flux</span> in ELMy H-mode on the COMPASS tokamak</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Adamek, J.; Seidl, J.; Komm, M.; Weinzettl, V.; Panek, R.; Stöckel, J.; Hron, M.; Hacek, P.; Imrisek, M.; Vondracek, P.; Horacek, J.; Devitre, A.; the COMPASS Team</p> <p>2017-02-01</p> <p>We report the latest results on fast measurements of the <span class="hlt">electron</span> temperature and parallel heat <span class="hlt">flux</span> in the COMPASS tokamak scrape-off layer (SOL) and divertor region during ELMy H-mode plasmas. The system of ball-pen and Langmuir probes installed on the divertor target, the horizontal reciprocating manipulator and the fast data-acquisition system with sampling frequency rate f  =  5 MSa s-1 allow us to measure the <span class="hlt">electron</span> temperature and parallel heat <span class="hlt">flux</span> during inter-ELM and ELM periods with high temporal resolution. The filamentary structure of the <span class="hlt">electron</span> temperature and parallel heat <span class="hlt">flux</span> was observed during ELMs in the SOL as well as in the divertor region. The position of the filaments within ELMs is not regular and therefore the resulting conditionally averaged ELM neglects the peak values of the <span class="hlt">electron</span> temperature and parallel heat <span class="hlt">flux</span>. We have found a substantial difference between the value of the radial power decay length in the inter-ELM period λ q,inter  =  2.5 mm and the decay length of the peak ELM heat <span class="hlt">flux</span> λ q,ELM  =  13.1 mm. The decay length of the ELM energy density was found to be λ E,ELM  =  5.4 mm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5114644','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5114644"><span>High <span class="hlt">flux</span> circularly polarized gamma beam factory: coupling a Fabry-Perot optical cavity with an <span class="hlt">electron</span> storage ring</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chaikovska, I.; Cassou, K.; Chiche, R.; Cizeron, R.; Cornebise, P.; Delerue, N.; Jehanno, D.; Labaye, F.; Marie, R.; Martens, A.; Peinaud, Y.; Soskov, V.; Variola, A.; Zomer, F.; Cormier, E.; Lhermite, J.; Dolique, V.; Flaminio, R.; Michel, C.; Pinard, L.; Sassolas, B.; Akagi, T.; Araki, S.; Honda, Y.; Omori, T.; Terunuma, N.; Urakawa, J.; Miyoshi, S.; Takahashi, T.; Yoshitama, H.</p> <p>2016-01-01</p> <p>We report and discuss high-<span class="hlt">flux</span> generation of circularly polarized γ-rays by means of Compton scattering. The γ-ray beam results from the collision of an external-cavity-enhanced infrared laser beam and a low emittance relativistic <span class="hlt">electron</span> beam. By operating a non-planar bow-tie high-finesse optical Fabry-Perot cavity coupled to a storage ring, we have recorded a <span class="hlt">flux</span> of up to (3.5 ± 0.3) × 108 photons per second with a mean measured energy of 24 MeV. The γ-ray <span class="hlt">flux</span> has been sustained for several hours. In particular, we were able to measure a record value of up to 400 γ-rays per collision in a full bandwidth. Moreover, the impact of Compton scattering on the <span class="hlt">electron</span> beam dynamics could be observed resulting in a reduction of the <span class="hlt">electron</span> beam lifetime correlated to the laser power stored in the Fabry-Perot cavity. We demonstrate that the <span class="hlt">electron</span> beam lifetime provides an independent and consistent determination of the γ-ray <span class="hlt">flux</span>. Furthermore, a reduction of the γ-ray <span class="hlt">flux</span> due to intrabeam scattering has clearly been identified. These results, obtained on an accelerator test facility, warrant potential scaling and revealed both expected and yet unobserved effects. They set the baseline for further scaling of the future Compton sources under development around the world. PMID:27857146</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27934925','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27934925"><span>Set anode potentials affect the <span class="hlt">electron</span> <span class="hlt">fluxes</span> and microbial community structure in propionate-fed microbial electrolysis cells.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hari, Ananda Rao; Katuri, Krishna P; Logan, Bruce E; Saikaly, Pascal E</p> <p>2016-12-09</p> <p>Anode potential has been shown to be a critical factor in the rate of acetate removal in microbial electrolysis cells (MECs), but studies with fermentable substrates and set potentials are lacking. Here, we examined the impact of three different set anode potentials (SAPs; -0.25, 0, and 0.25 V vs. standard hydrogen electrode) on the electrochemical performance, <span class="hlt">electron</span> <span class="hlt">flux</span> to various sinks, and anodic microbial community structure in two-chambered MECs fed with propionate. Electrical current (49-71%) and CH4 (22.9-41%) were the largest <span class="hlt">electron</span> sinks regardless of the potentials tested. Among the three SAPs tested, 0 V showed the highest <span class="hlt">electron</span> <span class="hlt">flux</span> to electrical current (71 ± 5%) and the lowest <span class="hlt">flux</span> to CH4 (22.9 ± 1.2%). In contrast, the SAP of -0.25 V had the lowest <span class="hlt">electron</span> <span class="hlt">flux</span> to current (49 ± 6%) and the highest <span class="hlt">flux</span> to CH4 (41.1 ± 2%). The most dominant genera detected on the anode of all three SAPs based on 16S rRNA gene sequencing were Geobacter, Smithella and Syntrophobacter, but their relative abundance varied among the tested SAPs. Microbial community analysis implies that complete degradation of propionate in all the tested SAPs was facilitated by syntrophic interactions between fermenters and Geobacter at the anode and ferementers and hydrogenotrophic methanogens in suspension.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...636569C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...636569C"><span>High <span class="hlt">flux</span> circularly polarized gamma beam factory: coupling a Fabry-Perot optical cavity with an <span class="hlt">electron</span> storage ring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chaikovska, I.; Cassou, K.; Chiche, R.; Cizeron, R.; Cornebise, P.; Delerue, N.; Jehanno, D.; Labaye, F.; Marie, R.; Martens, A.; Peinaud, Y.; Soskov, V.; Variola, A.; Zomer, F.; Cormier, E.; Lhermite, J.; Dolique, V.; Flaminio, R.; Michel, C.; Pinard, L.; Sassolas, B.; Akagi, T.; Araki, S.; Honda, Y.; Omori, T.; Terunuma, N.; Urakawa, J.; Miyoshi, S.; Takahashi, T.; Yoshitama, H.</p> <p>2016-11-01</p> <p>We report and discuss high-<span class="hlt">flux</span> generation of circularly polarized γ-rays by means of Compton scattering. The γ-ray beam results from the collision of an external-cavity-enhanced infrared laser beam and a low emittance relativistic <span class="hlt">electron</span> beam. By operating a non-planar bow-tie high-finesse optical Fabry-Perot cavity coupled to a storage ring, we have recorded a <span class="hlt">flux</span> of up to (3.5 ± 0.3) × 108 photons per second with a mean measured energy of 24 MeV. The γ-ray <span class="hlt">flux</span> has been sustained for several hours. In particular, we were able to measure a record value of up to 400 γ-rays per collision in a full bandwidth. Moreover, the impact of Compton scattering on the <span class="hlt">electron</span> beam dynamics could be observed resulting in a reduction of the <span class="hlt">electron</span> beam lifetime correlated to the laser power stored in the Fabry-Perot cavity. We demonstrate that the <span class="hlt">electron</span> beam lifetime provides an independent and consistent determination of the γ-ray <span class="hlt">flux</span>. Furthermore, a reduction of the γ-ray <span class="hlt">flux</span> due to intrabeam scattering has clearly been identified. These results, obtained on an accelerator test facility, warrant potential scaling and revealed both expected and yet unobserved effects. They set the baseline for further scaling of the future Compton sources under development around the world.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5146674','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5146674"><span>Set anode potentials affect the <span class="hlt">electron</span> <span class="hlt">fluxes</span> and microbial community structure in propionate-fed microbial electrolysis cells</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hari, Ananda Rao; Katuri, Krishna P.; Logan, Bruce E.; Saikaly, Pascal E.</p> <p>2016-01-01</p> <p>Anode potential has been shown to be a critical factor in the rate of acetate removal in microbial electrolysis cells (MECs), but studies with fermentable substrates and set potentials are lacking. Here, we examined the impact of three different set anode potentials (SAPs; −0.25, 0, and 0.25 V vs. standard hydrogen electrode) on the electrochemical performance, <span class="hlt">electron</span> <span class="hlt">flux</span> to various sinks, and anodic microbial community structure in two-chambered MECs fed with propionate. Electrical current (49–71%) and CH4 (22.9–41%) were the largest <span class="hlt">electron</span> sinks regardless of the potentials tested. Among the three SAPs tested, 0 V showed the highest <span class="hlt">electron</span> <span class="hlt">flux</span> to electrical current (71 ± 5%) and the lowest <span class="hlt">flux</span> to CH4 (22.9 ± 1.2%). In contrast, the SAP of −0.25 V had the lowest <span class="hlt">electron</span> <span class="hlt">flux</span> to current (49 ± 6%) and the highest <span class="hlt">flux</span> to CH4 (41.1 ± 2%). The most dominant genera detected on the anode of all three SAPs based on 16S rRNA gene sequencing were Geobacter, Smithella and Syntrophobacter, but their relative abundance varied among the tested SAPs. Microbial community analysis implies that complete degradation of propionate in all the tested SAPs was facilitated by syntrophic interactions between fermenters and Geobacter at the anode and ferementers and hydrogenotrophic methanogens in suspension. PMID:27934925</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JPSCP...1a5030Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JPSCP...1a5030Y"><span>Probability Density Functions of Floating Potential Fluctuations Due to Local <span class="hlt">Electron</span> <span class="hlt">Flux</span> Intermittency in a Linear ECR Plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yoshimura, Shinji; Terasaka, Kenichiro; Tanaka, Eiki; Aramaki, Mitsutoshi; Tanaka, Masayoshi Y.</p> <p></p> <p>An intermittent behavior of local <span class="hlt">electron</span> <span class="hlt">flux</span> in a laboratory ECR plasma is statistically analyzed by means of probability density functions (PDFs). The PDF constructed from a time series of the floating potential signal on a Langmuir probe has a fat tail in the negative value side, which reflects the intermittency of the local <span class="hlt">electron</span> <span class="hlt">flux</span>. The PDF of the waiting time, which is defined by the time interval between two successive events, is found to exhibit an exponential distribution, suggesting that the phenomenon is characterized by a stationary Poisson process. The underlying Poisson process is also confirmed by the number of events in given time intervals that is Poisson distributed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRA..119.1102H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRA..119.1102H"><span>Variability and spatial fine structure of precipitating and trapped medium-energy <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the noon sector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hargreaves, J. K.; Birch, M. J.; Evans, D. S.</p> <p>2014-02-01</p> <p>The relationships between the precipitating and trapped components of magnetospheric <span class="hlt">electron</span> <span class="hlt">flux</span> for energy ranges exceeding 30 and 100 keV have been investigated using data from polar orbiting satellites, the study being restricted to a limited geographic region at auroral latitudes in the noon sector. The <span class="hlt">electron</span> <span class="hlt">flux</span> of these energies is the cause of auroral radio absorption. The data are analyzed at two levels of detail. Variations between different passes are studied using their median values, and variations within passes are derived from individual data points at 2 s intervals, equivalent to about 10 km in distance. Several types of behavior are recognized. Basically, the ratio of precipitating to trapped <span class="hlt">flux</span> at energies exceeding 30 keV varies in proportion to the trapped <span class="hlt">flux</span>, though there is a limiting upper value where the two components are approximately equal. The precipitating <span class="hlt">flux</span> never exceeds the trapped <span class="hlt">flux</span> by any significant amount. These types appear to be consistent with weak and strong pitch angle scatterings, respectively. The precipitation at >100 keV varies somewhat with the >100 keV trapped <span class="hlt">flux</span> but more strongly with the >30 keV component, consistent with scattering by chorus waves produced by <span class="hlt">electrons</span> less energetic than those being scattered. Comparison between the two energy ranges shows that the precipitating component is always softer than the trapped. The detailed relationship between the precipitating and trapped components varies from pass to pass by an amount related to the east-west component of the interplanetary magnetic field. Superimposed on the above behavior are large reductions of precipitation, spatial rather than temporal in nature, during which the trapped <span class="hlt">flux</span> remains virtually unchanged. These reductions appear to be due to structures some tens of kilometers across, perhaps related to "ducts" within the magnetosphere. Some theoretical considerations based on the Kennel and Petscheck theory of scattering are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23947779','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23947779"><span>Carbon and <span class="hlt">electron</span> <span class="hlt">fluxes</span> during the electricity driven 1,3-propanediol biosynthesis from glycerol.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Mi; Chen, Jingwen; Freguia, Stefano; Rabaey, Korneel; Keller, Jürg</p> <p>2013-10-01</p> <p>1,3-Propanediol (1,3-PDO) can be produced biologically through glycerol fermentation. While such a process typically involves a pure culture system, particularly for crude glycerol, there would be operational advantages if a mixed population could be used. However, in the latter case the yield is typically low. Here, we use electrical current as the driving force for a mixed population fermenting glycerol in the cathode of a microbial bioelectrochemical system (BES). The carbon and <span class="hlt">electron</span> flows were monitored by a titration and off-gas analysis (TOGA) sensor, and the syntrophic interactions in the BES were also investigated. Results show that on a carbon yield basis, current enhanced 1,3-PDO production from 24.8% (without current) to 50.1% (with a polarized biocathode at -0.9 V versus standard hydrogen electrode, SHE). <span class="hlt">Flux</span> analysis indicated that the reductive current can be integrated into glycerol metabolism to enhance 1,3-PDO yield and that glycerol metabolism was redirected from propionate fermentation to 1,3-PDO production. A polarization of -0.6 V (vs SHE) resulted in more fermentative hydrogen production (from 2.7% to 8.0% on <span class="hlt">electron</span> basis). 1,3-PDO production was also enhanced with hydrogen supply (37.7% on carbon basis), by suppressing hydrogen fermentation. Moreover, interspecies hydrogen transfer encouraged hydrogenotrophic methanogenesis, which was also accelerated by the cathodic polarization.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSA33A1989G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSA33A1989G"><span>Predicting <span class="hlt">Electron</span> Energy <span class="hlt">Flux</span> Using Ground-Based Multi-Spectral Auroral Imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grubbs, G. A.; Samara, M.; Michell, R.; Redmon, R. J.</p> <p>2013-12-01</p> <p>High-resolution, multi-spectral auroral observations can now be routinely acquired using the Multi-spectral Observatory Of Sensitive EMCCDs (MOOSE), currently installed in Poker Flat, AK. Observations from the past 2 auroral seasons have yielded many simultaneous auroral observations in 4 different emission lines (427.8 nm, 557.7 nm, 630 nm, and 844.6 nm). From these data, the brightness of the absolute auroral emissions will be calculated. Combined with atmospheric modeling, auroral emission brightness will be used to predict the total energy <span class="hlt">flux</span> and characteristic energy of the <span class="hlt">electrons</span> responsible for the aurora. The theory behind this method is only developed for auroral measurements in the magnetic zenith, and therefore it is not known to what extent it can be applied off zenith. All-sky auroral image data will be examined and compared with DMSP satellite overpasses to quantify the extent to which the model can make predictions off-zenith, creating an empirical model that could then be applied to the many cases without overpasses. This will lead to large-scale 2-D maps of <span class="hlt">electron</span> precipitation characteristics which can contribute to global ionospheric models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM31A2437B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM31A2437B"><span>Statistical Study of <span class="hlt">electron</span> <span class="hlt">flux</span> dropouts at GEO : occurrences, magnitudes, and main driving factors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boynton, R.; Mourenas, D.; Balikhin, M. A.</p> <p>2016-12-01</p> <p>Large decreases of <span class="hlt">electron</span> <span class="hlt">flux</span> were investigated for a range of energies, from 24.1 keV to 2.7 MeV. These dropouts are defined by a decrease of a factor of 4 in one day or a factor of 9 in two days, where each day has at least a factor of 2.5 decrease. These decrease were automatically identified. The statistics of these decreases were then studied. These statistics include the mean time between dropouts and the mean magnitude of each dropout. Also the Error Reduction ratio (ERR) analysis in the Forward Regression Orthogonal Least Squares (FROLS) algorithm was used to find a relationship of the energetic <span class="hlt">electron</span> depletion with the solar wind and geomagnetic indices. Different dropout occurrences and magnitudes were found in three distinct energy ranges, lower than 100 keV, 100-600 keV, and larger than 600 keV, corresponding to different groups of drivers and loss processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1258662-first-fermi-lat-supernova-remnant-catalog','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1258662-first-fermi-lat-supernova-remnant-catalog"><span>The first Fermi <span class="hlt">LAT</span> supernova remnant catalog</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Acero, F.</p> <p>2016-05-16</p> <p>To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the Fermi Large Area Telescope. Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 <span class="hlt">flux</span> upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude, allows us to determine an upper limit of 22% on the number of GeV candidatesmore » falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi <span class="hlt">LAT</span> analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, demonstrates the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. As a result, we model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22570237','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22570237"><span>A <span class="hlt">flux</span>-splitting method for hyperbolic-equation system of magnetized <span class="hlt">electron</span> fluids in quasi-neutral plasmas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kawashima, Rei Komurasaki, Kimiya Schönherr, Tony</p> <p>2016-04-01</p> <p>A <span class="hlt">flux</span>-splitting method is proposed for the hyperbolic-equation system (HES) of magnetized <span class="hlt">electron</span> fluids in quasi-neutral plasmas. The numerical <span class="hlt">fluxes</span> are split into four categories, which are computed by using an upwind method which incorporates a <span class="hlt">flux</span>-vector splitting (FVS) and advection upstream splitting method (AUSM). The method is applied to a test calculation condition of uniformly distributed and angled magnetic lines of force. All of the pseudo-time advancement terms converge monotonically and the conservation laws are strictly satisfied in the steady state. The calculation results are compared with those computed by using the elliptic–parabolic-equation system (EPES) approach using a magnetic-field-aligned mesh (MFAM). Both qualitative and quantitative comparisons yield good agreements of results, indicating that the HES approach with the <span class="hlt">flux</span>-splitting method attains a high computational accuracy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TESS....120505P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TESS....120505P"><span>Observations and Interpretation of Behind the Limb Solar Flares Detected by Fermi-<span class="hlt">LAT</span> and Other Instruments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petrosian, Vahe; Omodei, Nicola; Pesce-Rollins, Melissa; Rubio da Costa, Fatima; Liu, Wei</p> <p>2015-04-01</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) is the most sensitive instrument ever deployed in space for observing > 30 MeV gamma-rays. During the past active period of the Sun the <span class="hlt">LAT</span> has detected more than 40 flares up to GeV energies some of which occur behind the limb as determined by STEREO observations. We will present the observations on two such flares with significant <span class="hlt">flux</span> of > 100 MeV (and some indication of 1 to 10 MeV detected by Fermi-GBM) gamma-rays coming from the visible disk while the flare and associated CMEs are initiated in active regions tens of degrees behind the visible limb of the Sun. We will consider acceleration of particles, their transport and radiative signatures, and the transfer of these radiation in the solar atmosphere to distinguish between (i) acceleration in the low corona, in a high corona trap, and/or in the CME driven shock; (ii) between continuous and prompt acceleration; and (iii) between <span class="hlt">electron</span> bremsstrahlung and decay of pions produced by accelerated ions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1357522','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1357522"><span><I>Fermi</I> -<span class="hlt">Lat</span> Study Of Gamma-Ray Emission In The Direction Of Supernova Remnant W49B</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.</p> <p>2010-09-29</p> <p>We present an analysis of the gamma-ray data obtained with the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope in the direction of SNR W49B (G43.3–0.2). A bright unresolved gamma-ray source detected at a significance of 38σ is found to coincide with SNR W49B. The energy spectrum in the 0.2-200 GeV range gradually steepens toward high energies. The luminosity is estimated to be 1.5 × 10<sup>36</sup> (D/8 kpc)<sup>2</sup> erg s<sup>–1</sup> in this energy range. There is no indication that the gamma-ray emission comes from a pulsar. Assuming that the supernova remnant (SNR) shell is the site of gamma-ray production, the observed spectrum can be explained either by the decay of neutral π mesons produced through the proton-proton collisions or by <span class="hlt">electron</span> bremsstrahlung. The calculated energy density of relativistic particles responsible for the <span class="hlt">LAT</span> <span class="hlt">flux</span> is estimated to be remarkably large, U <sub>e,p</sub> >10<sup>4</sup> eV cm<sup>–3</sup>, for either gamma-ray production mechanism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357522-fermi-lat-study-gamma-ray-emission-direction-supernova-remnant-w49b','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357522-fermi-lat-study-gamma-ray-emission-direction-supernova-remnant-w49b"><span>Fermi -<span class="hlt">Lat</span> Study Of Gamma-Ray Emission In The Direction Of Supernova Remnant W49B</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Abdo, A. A.</p> <p>2010-09-29</p> <p>We present an analysis of the gamma-ray data obtained with the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope in the direction of SNR W49B (G43.3–0.2). A bright unresolved gamma-ray source detected at a significance of 38σ is found to coincide with SNR W49B. The energy spectrum in the 0.2-200 GeV range gradually steepens toward high energies. The luminosity is estimated to be 1.5 × 1036 (D/8 kpc)2 erg s–1 in this energy range. There is no indication that the gamma-ray emission comes from a pulsar. Assuming that the supernova remnant (SNR) shell is the site ofmore » gamma-ray production, the observed spectrum can be explained either by the decay of neutral π mesons produced through the proton-proton collisions or by <span class="hlt">electron</span> bremsstrahlung. The calculated energy density of relativistic particles responsible for the <span class="hlt">LAT</span> <span class="hlt">flux</span> is estimated to be remarkably large, U e,p >104 eV cm–3, for either gamma-ray production mechanism.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.1789D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.1789D"><span>On the origin of low-energy <span class="hlt">electrons</span> in the inner magnetosphere: <span class="hlt">Fluxes</span> and pitch-angle distributions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Denton, M. H.; Reeves, G. D.; Larsen, B. A.; Friedel, R. F. W.; Thomsen, M. F.; Fernandes, P. A.; Skoug, R. M.; Funsten, H. O.; Sarno-Smith, L. K.</p> <p>2017-02-01</p> <p>Accurate knowledge of the plasma <span class="hlt">fluxes</span> in the inner magnetosphere is essential for both scientific and programmatic applications. Knowledge of the low-energy <span class="hlt">electrons</span> (approximately tens to hundreds of eV) in the inner magnetosphere is particularly important since these <span class="hlt">electrons</span> are acted upon by various physical processes, accelerating the <span class="hlt">electrons</span> to higher energies, and also causing their loss. However, measurements of low-energy <span class="hlt">electrons</span> are challenging, and as a result, this population has been somewhat neglected previously. This study concerns observations of low-energy <span class="hlt">electrons</span> made by the Helium Oxygen Proton <span class="hlt">Electron</span> instrument on board the Van Allen Probes satellites and also observations from geosynchronous orbit made by the Magnetospheric Plasma Analyzer on board Los Alamos National Laboratory satellites. The <span class="hlt">fluxes</span> of <span class="hlt">electrons</span> from 30 eV to 1 keV are quantified as a function of pitch-angle, McIlwain L parameter, and local time for both quiet and active periods. Results indicate two sources for low-energy <span class="hlt">electrons</span> in this energy range: the low-energy tail of the <span class="hlt">electron</span> plasma sheet and the high-energy tail of the dayside ionosphere. These populations are identified primarily as a result of their different pitch-angle distributions. Field-aligned outflows from the dayside ionosphere are observed at all L shells during quiet and active periods. Our results also demonstrate that the dayside <span class="hlt">electron</span> field-aligned <span class="hlt">fluxes</span> at 30 eV are particularly strong between L values of 6 and 7, indicating an enhanced source within the polar ionosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26799383','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26799383"><span>Concerted <span class="hlt">Electronic</span> and Nuclear <span class="hlt">Fluxes</span> During Coherent Tunnelling in Asymmetric Double-Well Potentials.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bredtmann, Timm; Manz, Jörn; Zhao, Jian-Ming</p> <p>2016-05-19</p> <p>The quantum theory of concerted <span class="hlt">electronic</span> and nuclear <span class="hlt">fluxes</span> (CENFs) during coherent periodic tunnelling from reactants (R) to products (P) and back to R in molecules with asymmetric double-well potentials is developed. The results are deduced from the solution of the time-dependent Schrödinger equation as a coherent superposition of two eigenstates; here, these are the two states of the lowest tunnelling doublet. This allows the periodic time evolutions of the resulting <span class="hlt">electronic</span> and nuclear probability densities (EPDs and NPDs) as well as the CENFs to be expressed in terms of simple sinusodial functions. These analytical results reveal various phenomena during coherent tunnelling in asymmetric double-well potentials, e.g., all EPDs and NPDs as well as all CENFs are synchronous. Distortion of the symmetric reference to a system with an asymmetric double-well potential breaks the spatial symmetry of the EPDs and NPDs, but, surprisingly, the symmetry of the CENFs is conserved. Exemplary application to the Cope rearrangement of semibullvalene shows that tunnelling of the ideal symmetric system can be suppressed by asymmetries induced by rather small external electric fields. The amplitude for the half tunnelling, half nontunnelling border is as low as 0.218 × 10(-8) V/cm. At the same time, the delocalized eigenstates of the symmetric reference, which can be regarded as Schrödinger's cat-type states representing R and P with equal probabilities, get localized at one or the other minima of the asymmetric double-well potential, representing either R or P.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007PhyC..455...19B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007PhyC..455...19B"><span><span class="hlt">Flux</span> pinning by Al-based nanoparticles embedded in YBCO: A transmission <span class="hlt">electron</span> microscopic study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ben Azzouz, F.; Zouaoui, M.; Mellekh, A.; Annabi, M.; Van Tendeloo, G.; Ben Salem, M.</p> <p>2007-05-01</p> <p>A series of YBa2Cu3Oy (YBCO) samples with small amounts (0-0.6 wt.%) of nanosized alumina particles (50 nm) are synthesized in air by solid state reaction. The microstructure has been characterized by transmission <span class="hlt">electron</span> microscopy (TEM) and the critical current density Jc has been measured by the standard four-probe method in the applied magnetic field at 77 K. TEM and energy dispersive X-ray spectroscopy (EDS) analysis have shown that alumina reacts with the YBCO matrix to form nanometric aluminium-rich inhomogeneities intergrown within the YBCO superconducting matrix. These inhomogeneities reduce the onset transition temperature Tconset and the zero resistance temperature Tc. In spite of the monotonic decrease of the superconducting temperature Tc with increasing alumina addition, the Jc(H) behaviour is remarkably improved. The characteristic behaviour of Jc can be explained in terms of the counterbalance of two effects simultaneously caused by the nanometric alumina addition in the system. One effect is the formation of the Al-rich nanometric inhomogeneities relevant for the <span class="hlt">flux</span> pinning, and the other effect is the reduction of matrix superconducting volume, which is reflected by a decrease of the critical current density Jc at zero applied magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992NucFu..32.1755M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992NucFu..32.1755M"><span>Heat <span class="hlt">flux</span> of fast <span class="hlt">electrons</span> to the limiter in lower hybrid current drive plasma on WT-3</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maekawa, T.; Nakamura, M.; Komatsu, T.; Kishino, T.; Kishigami, Y.; Makino, K.; Maehara, T.; Minami, T.; Hanada, K.; Iida, M.; Terumichi, Y.; Tanaka, S.</p> <p>1992-10-01</p> <p>The heat <span class="hlt">flux</span> of fast <span class="hlt">electrons</span> to the local limiter in LHCD plasmas in WT-3 has been investigated by thermal measurement of the limiter. The amount of the heat <span class="hlt">flux</span> (PFE) is found to be about on third of the net radiofrequency power (Prf) injected into the plasma for various discharge conditions. The results combined with other measurements show that the confinement of fast <span class="hlt">electrons</span> deteriorates as Prf increases. This direct loss of fast <span class="hlt">electrons</span> is one of the causes of the degradation of the current drive efficiency. Heat transport of the bulk <span class="hlt">electrons</span> is also found to increase as Prf increases. Experimental results indicate that a significant part of the remaining RF power (2Prf/3) flows to the bulk <span class="hlt">electrons</span>. The slowing down power of fast <span class="hlt">electrons</span> in the energy range above several tens of keV is estimated to be quite small compared with 2Prf/3, suggesting that a significant part of the remaining power flows to the bulk <span class="hlt">electrons</span> via other channels. A plausible channel is the absorption of RF power via lower energy <span class="hlt">electrons</span> by an upshift of the parallel refractive index of the injected lower hybrid waves. This seems to be another cause of the degradation of the current drive efficiency</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15644356','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15644356"><span>Microgravity experiments on boiling and applications: research activity of advanced high heat <span class="hlt">flux</span> cooling technology for <span class="hlt">electronic</span> devices in Japan.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Suzuki, Koichi; Kawamura, Hiroshi</p> <p>2004-11-01</p> <p>Research and development on advanced high heat <span class="hlt">flux</span> cooling technology for <span class="hlt">electronic</span> devices has been carried out as the Project of Fundamental Technology Development for Energy Conservation, promoted by the New Energy and Industrial Technology Development Organization of Japan (NEDO). Based on the microgravity experiments on boiling heat transfer, the following useful results have obtained for the cooling of <span class="hlt">electronic</span> devices. In subcooled flow boiling in a small channel, heat <span class="hlt">flux</span> increases considerably more than the ordinary critical heat <span class="hlt">flux</span> with microbubble emission in transition boiling, and dry out of the heating surface is disturbed. Successful enhancement of heat transfer is achieved by a capillary effect from grooved surface dual subchannels on the liquid supply. The critical heat <span class="hlt">flux</span> increases 30-40 percent more than for ordinary subchannels. A self-wetting mechanism has been proposed, following investigation of bubble behavior in pool boiling of binary mixtures under microgravity. Ideas and a new concept have been proposed for the design of future cooling system in power <span class="hlt">electronics</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011HEAD...12.1203A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011HEAD...12.1203A"><span>Extracting the Size of the Cosmic <span class="hlt">Electron</span>-Positron Anomaly</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Auchettl, Katie; Balazs, C.</p> <p>2011-09-01</p> <p>Over the last few decades, numerous observations have hinted at an excess of high energy positrons in our locality. The most recent of these experiments has been the positron fraction measured by the PAMELA satellite and the <span class="hlt">electron</span> plus positron spectrum as measured by the Fermi-<span class="hlt">LAT</span> satellite. Since the release of these measurements, there have been a plethora of papers where authors invoke new physics ranging from, modification of the cosmic ray propagation, supernova remnants and dark matter annihilation. Using a Bayesian likelihood analysis, we isolate the anomalous contribution of the cosmic <span class="hlt">electron</span>-positron <span class="hlt">flux</span>. A significant tension was found between the <span class="hlt">electron</span> positron related data and non-<span class="hlt">electron</span>-positron cosmic ray <span class="hlt">fluxes</span>. Using 219 recent cosmic ray datum, we extracted the preferred values of the selected cosmic ray propagation parameters from the non-<span class="hlt">electron</span>-positron related measurements. Based on these parameter values we calculated background predictions with uncertainties for PAMELA and Fermi-<span class="hlt">LAT</span>. We found a deviation between the PAMELA and Fermi-<span class="hlt">LAT</span> data and the predicted background even when uncertainties, including systematics, were taken into account. Interpreting this as a hint of new physics, we subtracted the background from the data extracting the size, shape and uncertainty of the anomalous contribution in a model independent fashion. We briefly compared the extracted signal to some theoretical results predicting such an anomaly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1356602','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1356602"><span><i>Fermi</i>-<span class="hlt">LAT</span> and <i>Suzaku</i> observations of the radio galaxy Centaurus B</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Katsuta, J.; Tanaka, Y. T.; Stawarz, Ł.; O’Sullivan, S. P.; Cheung, C. C.; Kataoka, J.; Funk, S.; Yuasa, T.; Odaka, H.; Takahashi, T.; Svoboda, J.</p> <p>2013-01-28</p> <p>Centaurus B is a nearby radio galaxy positioned in the southern hemisphere close to the Galactic plane. Here, in this work, we present a detailed analysis of about 43 months of accumulated Fermi-<span class="hlt">LAT</span> data of the γ-ray counterpart of the source initially reported in the 2nd Fermi-<span class="hlt">LAT</span> catalog, and of newly acquired Suzaku X-ray data. We confirm its detection at GeV photon energies and analyze the extension and variability of the γ-ray source in the <span class="hlt">LAT</span> dataset, in which it appears as a steady γ-ray emitter. The X-ray core of Centaurus B is detected as a bright source of a continuum radiation. We do not detect, however, any diffuse X-ray emission from the known radio lobes, with the provided upper limit only marginally consistent with the previously claimed ASCA <span class="hlt">flux</span>. Two scenarios that connect the X-ray and γ-ray properties are considered. In the first one, we assume that the diffuse non-thermal X-ray emission component is not significantly below the derived Suzaku upper limit. In this case, modeling the inverse-Compton emission shows that the observed γ-ray <span class="hlt">flux</span> of the source may in principle be produced within the lobes. This association would imply that efficient in-situ acceleration of the radiating <span class="hlt">electrons</span> is occurring and that the lobes are dominated by the pressure from the relativistic particles. In the second scenario, with the diffuse X-ray emission well below the Suzaku upper limits, the lobes in the system are instead dominated by the magnetic pressure. In this case, the observed γ-ray <span class="hlt">flux</span> is not likely to be produced within the lobes, but instead within the nuclear parts of the jet. In conclusion, by means of synchrotron self-Compton modeling, we show that this possibility could be consistent with the broad-band data collected for the unresolved core of Centaurus B, including the newly derived Suzaku spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...824L..20A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...824L..20A"><span>Minute-timescale >100 MeV γ-Ray Variability during the Giant Outburst of Quasar 3C 279 Observed by Fermi-<span class="hlt">LAT</span> in 2015 June</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ackermann, M.; Anantua, R.; Asano, K.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Becerra Gonzalez, J.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Bruel, P.; Buehler, R.; Caliandro, G. A.; Cameron, R. A.; Caragiulo, M.; Caraveo, P. A.; Cavazzuti, E.; Cecchi, C.; Cheung, C. C.; Chiang, J.; Chiaro, G.; Ciprini, S.; Cohen-Tanugi, J.; Costanza, F.; Cutini, S.; D'Ammando, F.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Fegan, S. J.; Ferrara, E. C.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giordano, F.; Giroletti, M.; Grenier, I. A.; Guillemot, L.; Guiriec, S.; Hayashida, M.; Hays, E.; Horan, D.; Jóhannesson, G.; Kensei, S.; Kocevski, D.; Kuss, M.; La Mura, G.; Larsson, S.; Latronico, L.; Li, J.; Longo, F.; Loparco, F.; Lott, B.; Lovellette, M. N.; Lubrano, P.; Madejski, G. M.; Magill, J. D.; Maldera, S.; Manfreda, A.; Mayer, M.; Mazziotta, M. N.; Michelson, P. F.; Mirabal, N.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Nalewajko, K.; Negro, M.; Nuss, E.; Ohsugi, T.; Orlando, E.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Principe, G.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Scargle, J. D.; Sgrò, C.; Sikora, M.; Simone, D.; Siskind, E. J.; Spada, F.; Spinelli, P.; Stawarz, L.; Thayer, J. B.; Thompson, D. J.; Torres, D. F.; Troja, E.; Uchiyama, Y.; Yuan, Y.; Zimmer, S.</p> <p>2016-06-01</p> <p>On 2015 June 16, Fermi-<span class="hlt">LAT</span> observed a giant outburst from the flat spectrum radio quasar 3C 279 with a peak >100 MeV <span class="hlt">flux</span> of ˜3.6 × 10-5 photons cm-2 s-1, averaged over orbital period intervals. It is historically the highest γ-ray <span class="hlt">flux</span> observed from the source, including past EGRET observations, with the γ-ray isotropic luminosity reaching ˜1049 erg s-1. During the outburst, the Fermi spacecraft, which has an orbital period of 95.4 minutes, was operated in a special pointing mode to optimize the exposure for 3C 279. For the first time, significant <span class="hlt">flux</span> variability at sub-orbital timescales was found in blazar observations by Fermi-<span class="hlt">LAT</span>. The source <span class="hlt">flux</span> variability was resolved down to 2-minute binned timescales, with <span class="hlt">flux</span> doubling times of less than 5 minutes. The observed minute-scale variability suggests a very compact emission region at hundreds of Schwarzschild radii from the central engine in conical jet models. A minimum bulk jet Lorentz factor (Γ) of 35 is necessary to avoid both internal γ-ray absorption and super-Eddington jet power. In the standard external radiation Comptonization scenario, Γ should be at least 50 to avoid overproducing the synchrotron self-Compton component. However, this predicts extremely low magnetization (˜5 × 10-4). Equipartition requires Γ as high as 120, unless the emitting region is a small fraction of the dissipation region. Alternatively, we consider γ rays originating as synchrotron radiation of γ e ˜ 1.6 × 106 <span class="hlt">electrons</span>, in a magnetic field B ˜ 1.3 kG, accelerated by strong electric fields E ˜ B in the process of magnetoluminescence. At such short distance scales, one cannot immediately exclude the production of γ-rays in hadronic processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ATel.9588....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ATel.9588....1C"><span>Fermi-<span class="hlt">LAT</span> confirmation of enhanced gamma-ray activity from the Crab nebula</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheung, C. C.</p> <p>2016-10-01</p> <p>Preliminary <span class="hlt">LAT</span> analysis confirms the recent enhanced gamma-ray activity from the Crab nebula detected by AGILE (ATel #9586). The daily-averaged gamma-ray <span class="hlt">fluxes</span> (E > 100 MeV) from the direction of the Crab Nebula were (4.8 +/- 0.5) x 10^-6 ph cm^-2 s^-1 (Sep 30), (3.3 +/- 0.4) x 10^-6 ph cm^-2 s^-1 (Oct 1), and (4.5 +/- 0.5) x 10^-6 ph cm^-2 s^-1 (Oct 2). These are up to a factor of ~1.8 greater than the average gamma-ray <span class="hlt">flux</span> of (2.71 +/- 0.02) x 10^-6 ph cm^-2 s^-1 reported in the third Fermi-<span class="hlt">LAT</span> source catalog (Acero et al. 2015, ApJS, 218, 23). All <span class="hlt">fluxes</span> given are the sums of the pulsar and nebular emission, and with statistical uncertainties only.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840030076&hterms=ghost&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dghost','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840030076&hterms=ghost&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dghost"><span>The Mimas ghost revisited - An analysis of the <span class="hlt">electron</span> <span class="hlt">flux</span> and <span class="hlt">electron</span> microsignatures observed in the vicinity of Mimas at Saturn</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chenette, D. L.; Stone, E. C.</p> <p>1983-01-01</p> <p>An analysis of the <span class="hlt">electron</span>-absorption signature observed by the cosmic-ray system on Voyager 2 near the orbit of Mimas is presented. It is found that these observations cannot be explained as the absorption signature of Mimas. By combining Pioneer 11 and Voyager 2 measurements of the <span class="hlt">electron</span> <span class="hlt">flux</span> at Mimas's orbit (L = 3.1), an <span class="hlt">electron</span> spectrum is found in which most of the <span class="hlt">flux</span> above about 100 keV is concentrated near 1 to 3 MeV. This spectral form is qualitatively consistent with the bandpass filter model of Van Allen et al. (1980). The expected Mimas absorption signature is calculated from this spectrum neglecting radial diffusion. Since no Mimas absorption signature was observed in the inbound Voyager 2 data, a lower limit on the diffusion coefficient for MeV <span class="hlt">electrons</span> at L = 3.1 of D greater than 10 to the -8th sq Saturn radii/sec is obtained. With a diffusion coefficient this large, both the Voyager 2 and the Pioneer 11 small-scale <span class="hlt">electron</span>-absorption-signature observations in Mimas's orbit are enigmatic. Thus the mechanism for producing these signatures is referred to as the Mimas ghost. A cloud of material in orbit with Mimas may account for the observed <span class="hlt">electron</span> signature if the cloud is at least 1-percent opaque to <span class="hlt">electrons</span> across a region extending over a few hundred kilometers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840030076&hterms=Ghost&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DGhost','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840030076&hterms=Ghost&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DGhost"><span>The Mimas ghost revisited - An analysis of the <span class="hlt">electron</span> <span class="hlt">flux</span> and <span class="hlt">electron</span> microsignatures observed in the vicinity of Mimas at Saturn</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chenette, D. L.; Stone, E. C.</p> <p>1983-01-01</p> <p>An analysis of the <span class="hlt">electron</span>-absorption signature observed by the cosmic-ray system on Voyager 2 near the orbit of Mimas is presented. It is found that these observations cannot be explained as the absorption signature of Mimas. By combining Pioneer 11 and Voyager 2 measurements of the <span class="hlt">electron</span> <span class="hlt">flux</span> at Mimas's orbit (L = 3.1), an <span class="hlt">electron</span> spectrum is found in which most of the <span class="hlt">flux</span> above about 100 keV is concentrated near 1 to 3 MeV. This spectral form is qualitatively consistent with the bandpass filter model of Van Allen et al. (1980). The expected Mimas absorption signature is calculated from this spectrum neglecting radial diffusion. Since no Mimas absorption signature was observed in the inbound Voyager 2 data, a lower limit on the diffusion coefficient for MeV <span class="hlt">electrons</span> at L = 3.1 of D greater than 10 to the -8th sq Saturn radii/sec is obtained. With a diffusion coefficient this large, both the Voyager 2 and the Pioneer 11 small-scale <span class="hlt">electron</span>-absorption-signature observations in Mimas's orbit are enigmatic. Thus the mechanism for producing these signatures is referred to as the Mimas ghost. A cloud of material in orbit with Mimas may account for the observed <span class="hlt">electron</span> signature if the cloud is at least 1-percent opaque to <span class="hlt">electrons</span> across a region extending over a few hundred kilometers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840004988','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840004988"><span>The Mimas ghost revisited: An analysis of the <span class="hlt">electron</span> <span class="hlt">flux</span> and <span class="hlt">electron</span> microsignatures observed in the vicinity of Mimas at Saturn</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chenette, D. L.; Stone, E. C.</p> <p>1983-01-01</p> <p>An analysis of the <span class="hlt">electron</span> absorption signature observed by the Cosmic Ray System (CRS) on Voyage 2 near the orbit of Mimas is presented. We find that these observations cannot be explained as the absorption signature of Mimas. Combing Pioneer 11 and Voyager 2 measurements of the <span class="hlt">electron</span> <span class="hlt">flux</span> at Mimas's orbit (L=3.1), we find an <span class="hlt">electron</span> spectrum where most of the <span class="hlt">flux</span> above approx 100 keV is concentrated near 1 to 3 MeV. The expected Mimas absorption signature is calculated from this spectrum neglecting radial diffusion. A lower limit on the diffusion coefficient for MeV <span class="hlt">electrons</span> is obtained. With a diffusion coefficient this large, both the Voyager 2 and the Pioneer 11 small-scale <span class="hlt">electron</span> absorption signature observations in Mimas's orbit are enigmatic. Thus we refer to the mechanism for producing these signatures as the Mimas ghost. A cloud of material in orbit with Mimas may account for the observed <span class="hlt">electron</span> signature if the cloud is at least 1% opaque to <span class="hlt">electrons</span> across a region extending over a few hundred kilometers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357531-fermi-lat-observations-geminga-pulsar','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357531-fermi-lat-observations-geminga-pulsar"><span>Fermi -<span class="hlt">Lat</span> Observations Of The Geminga Pulsar</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Abdo, A. A.</p> <p>2010-08-09</p> <p>We report on the Fermi-<span class="hlt">LAT</span> observations of the Geminga pulsar, the second brightest non-variable GeV source in the γ-ray sky and the first example of a radio-quiet γ-ray pulsar. The observations cover one year, from the launch of the Fermi satellite through 2009 June 15. A data sample of over 60,000 photons enabled us to build a timing solution based solely on γ-rays. Timing analysis shows two prominent peaks, separated by Δphgr = 0.497 ± 0.004 in phase, which narrow with increasing energy. Pulsed γ-rays are observed beyond 18 GeV, precluding emission below 2.7 stellar radii because of magnetic absorption.more » The phase-averaged spectrum was fitted with a power law with exponential cutoff of spectral index Γ = (1.30 ± 0.01 ± 0.04), cutoff energy E 0 = (2.46 ± 0.04 ± 0.17) GeV, and an integral photon <span class="hlt">flux</span> above 0.1 GeV of (4.14 ± 0.02 ± 0.32) × 10–6 cm–2 s–1. The first uncertainties are statistical and the second ones are systematic. The phase-resolved spectroscopy shows a clear evolution of the spectral parameters, with the spectral index reaching a minimum value just before the leading peak and the cutoff energy having maxima around the peaks. The phase-resolved spectroscopy reveals that pulsar emission is present at all rotational phases. The spectral shape, broad pulse profile, and maximum photon energy favor the outer magnetospheric emission scenarios.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991sctip.........P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991sctip.........P"><span>Magnetic topology of coronal mass ejections based on ISEE-3 observations of bidirectional <span class="hlt">electron</span> <span class="hlt">fluxes</span> at 1 AU</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Phillips, J. L.; Gosling, J. T.; McComas, D. J.; Bame, S. J.; Feldman, W. C.</p> <p></p> <p>The solar wind <span class="hlt">electron</span> heat <span class="hlt">flux</span> is carried primarily by superthermal halo <span class="hlt">electrons</span> with energies at 1 AU of approximately 80 eV and greater. These halo <span class="hlt">electrons</span> typically are beamed antisunward along the IMF, indicating effective magnetic connection to the Sun only in one direction. However, ISEE-3 <span class="hlt">electron</span> observations at 1 AU show that counterstreaming halo beams, suggesting closed magnetic structures, prevail within CMEs. These structures might be magnetic tongues, tied to the Sun at both ends, magnetically detached plasmoids, or perhaps complex <span class="hlt">flux</span> rope structures. We present the results of analysis of ISEE-3 <span class="hlt">electron</span> observations within 39 CME's. Parameters analyzed include: the asymmetry between the counterstreaming beams, control by the IMF orientation, and the variation of the <span class="hlt">electron</span> distributions as a particular CME convects past the spacecraft. We find that some CME's contain nearly symmetric <span class="hlt">electron</span> beams, while others are strongly asymmetric, and that beam propagating most nearly antisunward is generally dominant. The more nearly radial the IMF the greater is the symmetry between outward and inward beams. Trends observed as CME's propagate past the spacecraft probably result primarily from the compression of the leading edge. We present examples of a previously unreported strahl-on-strahl distribution, suggesting continued magnetic connection to the corona, in which a narrow antisunward beam is superimposed on a broader beam. Preliminary results show that such spectra are present in a substantial fraction of the observed CME's. Taken as a whole, our results appear to favor a tongue or <span class="hlt">flux</span> rope scenario rather than a detached plasmoid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005IJMPB..19.3483A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005IJMPB..19.3483A"><span>Effects of the Magnetic <span class="hlt">Flux</span> and of the <span class="hlt">Electron</span> Momentum on the Transmission Amplitude in the Aharonov-Bohm Interferometer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Amaresh Kumar, M. V.; Sahoo, Debendranath</p> <p></p> <p>A characterization of the two-terminal open-ring Aharonov-Bohm interferometer is made by analyzing the phase space plots in the complex transmission amplitude plane. Two types of plots are considered: type 1 plot uses the magnetic <span class="hlt">flux</span> as the variable parameter and type 2 plot which uses the <span class="hlt">electron</span> momentum as the variable parameter. In type 1 plot, the trajectory closes upon itself only when the ratio R of the arm lengths (of the interferometer) is a rational fraction, and the shape and the type of the generated flower-like pattern is sensitive to the <span class="hlt">electron</span> momentum. For momenta corresponding to discrete eigenstates of the perfect ring (i.e., the ring without the leads), the trajectory passes through the origin a certain fixed number of times before closing upon itself, whereas for arbitrary momenta it never passes through the origin. Although the transmission coefficient is periodic in the <span class="hlt">flux</span> with the elementary <span class="hlt">flux</span> quantum as the basic period, the phenomenon of <span class="hlt">electron</span> transmission is shown not to be so when analyzed via the present technique. The periodicity is seen to spread over several <span class="hlt">flux</span> units whenever R is a rational fraction whereas there is absolutely no periodicity present when R is an irrational number. In type 2 plot, closed trajectories passing through the origin a number of times are seen for R being a rational fraction. The case R = 1 (i.e., a symmetric ring) with zero <span class="hlt">flux</span> is rather pathological — it presents a closed loop surrounding the origin. For irrational R values, the trajectories never close.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4485056','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4485056"><span><span class="hlt">Flux</span> balance analysis reveals acetate metabolism modulates cyclic <span class="hlt">electron</span> flow and alternative glycolytic pathways in Chlamydomonas reinhardtii</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chapman, Stephen P.; Paget, Caroline M.; Johnson, Giles N.; Schwartz, Jean-Marc</p> <p>2015-01-01</p> <p>Cells of the green alga Chlamydomonas reinhardtii cultured in the presence of acetate perform mixotrophic growth, involving both photosynthesis and organic carbon assimilation. Under such conditions, cells exhibit a reduced capacity for photosynthesis but a higher growth rate, compared to phototrophic cultures. Better understanding of the down regulation of photosynthesis would enable more efficient conversion of carbon into valuable products like biofuels. In this study, <span class="hlt">Flux</span> Balance Analysis (FBA) and <span class="hlt">Flux</span> Variability Analysis (FVA) have been used with a genome scale model of C. reinhardtii to examine changes in intracellular <span class="hlt">flux</span> distribution in order to explain their changing physiology. Additionally, a reaction essentiality analysis was performed to identify which reaction subsets are essential for a given growth condition. Our results suggest that exogenous acetate feeds into a modified tricarboxylic acid (TCA) cycle, which bypasses the CO2 evolution steps, explaining increases in biomass, consistent with experimental data. In addition, reactions of the oxidative pentose phosphate and glycolysis pathways, inactive under phototrophic conditions, show substantial <span class="hlt">flux</span> under mixotrophic conditions. Importantly, acetate addition leads to an increased <span class="hlt">flux</span> through cyclic <span class="hlt">electron</span> flow (CEF), but results in a repression of CO2 fixation via Rubisco, explaining the down regulation of photosynthesis. However, although CEF enhances growth on acetate, it is not essential—impairment of CEF results in alternative metabolic pathways being increased. We have demonstrated how the reactions of photosynthesis interconnect with carbon metabolism on a global scale, and how systems approaches play a viable tool in understanding complex relationships at the scale of the organism. PMID:26175742</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26175742','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26175742"><span><span class="hlt">Flux</span> balance analysis reveals acetate metabolism modulates cyclic <span class="hlt">electron</span> flow and alternative glycolytic pathways in Chlamydomonas reinhardtii.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chapman, Stephen P; Paget, Caroline M; Johnson, Giles N; Schwartz, Jean-Marc</p> <p>2015-01-01</p> <p>Cells of the green alga Chlamydomonas reinhardtii cultured in the presence of acetate perform mixotrophic growth, involving both photosynthesis and organic carbon assimilation. Under such conditions, cells exhibit a reduced capacity for photosynthesis but a higher growth rate, compared to phototrophic cultures. Better understanding of the down regulation of photosynthesis would enable more efficient conversion of carbon into valuable products like biofuels. In this study, <span class="hlt">Flux</span> Balance Analysis (FBA) and <span class="hlt">Flux</span> Variability Analysis (FVA) have been used with a genome scale model of C. reinhardtii to examine changes in intracellular <span class="hlt">flux</span> distribution in order to explain their changing physiology. Additionally, a reaction essentiality analysis was performed to identify which reaction subsets are essential for a given growth condition. Our results suggest that exogenous acetate feeds into a modified tricarboxylic acid (TCA) cycle, which bypasses the CO2 evolution steps, explaining increases in biomass, consistent with experimental data. In addition, reactions of the oxidative pentose phosphate and glycolysis pathways, inactive under phototrophic conditions, show substantial <span class="hlt">flux</span> under mixotrophic conditions. Importantly, acetate addition leads to an increased <span class="hlt">flux</span> through cyclic <span class="hlt">electron</span> flow (CEF), but results in a repression of CO2 fixation via Rubisco, explaining the down regulation of photosynthesis. However, although CEF enhances growth on acetate, it is not essential-impairment of CEF results in alternative metabolic pathways being increased. We have demonstrated how the reactions of photosynthesis interconnect with carbon metabolism on a global scale, and how systems approaches play a viable tool in understanding complex relationships at the scale of the organism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850044805&hterms=energy+comparison&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Denergy%2Bcomparison','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850044805&hterms=energy+comparison&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Denergy%2Bcomparison"><span>A comparison of precipitating <span class="hlt">electron</span> energy <span class="hlt">flux</span> on March 22, 1979 with an empirical model - CDAW 6</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Simons, S. L., Jr.; Reiff, P. H.; Spiro, R. W.; Hardy, D. A.; Kroehl, H. W.</p> <p>1985-01-01</p> <p>Data recorded by Defense Meteorological Satellite Program, Tiros and P-78-1 satellites for the CDAW 6 event on March 22, 1979, have been compared with a statistical model of precipitating <span class="hlt">electron</span> <span class="hlt">fluxes</span>. Comparisons have been made on both an orbit-by-orbit basis and on a global basis by sorting and binning the data by AE index, invariant latitude, and magnetic local time in a manner similar to which the model was generated. It is concluded that the model <span class="hlt">flux</span> agrees with the data to within a factor of two, although small features and the exact locations of features are not consistently reproduced. In addition, the latitude of highest <span class="hlt">electron</span> precipitation usually occurs about 3 deg more poleward in the model than in the data. This discrepancy is attributed to ring current inflation of the storm time magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21420907','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21420907"><span>Ground-based observations of thunderstorm-correlated <span class="hlt">fluxes</span> of high-energy <span class="hlt">electrons</span>, gamma rays, and neutrons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chilingarian, A.; Daryan, A.; Arakelyan, K.; Hovhannisyan, A.; Mailyan, B.; Melkumyan, L.; Hovsepyan, G.; Chilingaryan, S.; Reymers, A.; Vanyan, L.</p> <p>2010-08-15</p> <p>The Aragats Space Environmental Center facilities continuously measure <span class="hlt">fluxes</span> of neutral and charged secondary cosmic ray incidents on the Earth's surface. Since 2003 in the 1-minute time series we have detected more than 100 enhancements in the <span class="hlt">electron</span>, gamma ray, and neutron <span class="hlt">fluxes</span> correlated with thunderstorm activities. During the periods of the count rate enhancements, lasting tens of minutes, millions of additional particles were detected. Based on the largest particle event of September 19, 2009, we show that our measurements support the existence of long-lasting particle multiplication and acceleration mechanisms in the thunderstorm atmosphere. For the first time we present the energy spectra of <span class="hlt">electrons</span> and gamma rays from the particle avalanches produced in the thunderstorm atmosphere, reaching the Earth's surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6712688','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6712688"><span>Spin <span class="hlt">flux</span> and magnetic solitons in an interacting two-dimensional <span class="hlt">electron</span> gas: Topology of two-valued wave functions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>John, S.; Golubentsev, A. )</p> <p>1995-01-01</p> <p>For a topological antiferromagnet on a square lattice, with the standard Hartree-Fock, spin-density-wave decoupling of the on-site Hubbard interaction, there is an exact mapping of the low-energy one-<span class="hlt">electron</span> excitation spectrum to a relativistic Dirac continuum field theory. In this field theory, the Dirac mass gap is precisely the Mott-Hubbard charge gap and the continuum field variable is an eight-component Dirac spinor describing the components of physical <span class="hlt">electron</span>-spin amplitude on each of the four sites of the elementary plaquette in the original Hubbard model. Within this continuum model we derive explicitly the existence of hedgehog Skyrmion textures as local minima of the classical magnetic energy. These magnetic solitons carry a topological winding number [mu] associated with the vortex rotation of the background magnetic moment field by a phase angle 2[pi][mu] along a path encircling the soliton. Such solitons also carry a spin <span class="hlt">flux</span> of [mu][pi] through the plaquette on which they are centered. The [mu]=1 hedgehog Skyrmion describes a local transition from the topological (antiperiodic) sector of the one-<span class="hlt">electron</span> Hilbert space to the nontopological sector. We derive from first principles the existence of deep level localized <span class="hlt">electronic</span> states within the Mott-Hubbard charge gap for the [mu]=1 and 2 solitons. The spectrum of localized states is symmetric about [ital E]=0 and each subgap <span class="hlt">electronic</span> level can be occupied by a pair of <span class="hlt">electrons</span> in which one <span class="hlt">electron</span> resides primarily on one sublattice and the second <span class="hlt">electron</span> on the other sublattice. It is suggested that <span class="hlt">flux</span>-carrying solitons and the subgap <span class="hlt">electronic</span> structure which they induce are important in understanding the physical behavior of doped Mott insulators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DPPNI3001H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DPPNI3001H"><span>The Role of ITG/TEM/ETG Cross-Scale Coupling in Explaining Experimental <span class="hlt">Electron</span> Heat <span class="hlt">Flux</span> and Profile Stiffness</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howard, N. T.</p> <p>2015-11-01</p> <p>Anomalous <span class="hlt">electron</span> thermal transport in tokamak plasmas is the ``great unsolved problem of tokamak transport physics'' [Batchelor Plasma Sci. Tec. 2007]. For years it has been speculated that short wavelength ETG turbulence plays a key role, but simulation capturing both ion and <span class="hlt">electron</span>-scale turbulence simultaneously had never been tested quantitatively against experiment due to extreme computational requirements. Only recently have gyrokinetic codes and supercomputing resources together been able to capture the physics of cross-scale coupling between long wavelength ITG/TEM and short wavelength ETG turbulence. In C-Mod, long wavelength simulations often under-predict <span class="hlt">electron</span> heat <span class="hlt">flux</span>. As a result, dedicated experiments have been performed in L-mode plasmas to validate multi-scale nonlinear gyrokinetic simulations. In this talk, the first set of full-physics, multi-scale simulations of a tokamak plasma performed with the GYRO code are compared to experiment. The simulations include coupled ITG/TEM/ETG turbulence (kθρs < 48 . 0) at realistic mass ratio (mi/me = 3600), with experimental inputs for impurities, geometry, ExB shear, and collisions. 100M CPU hours were required for six simulations to scan the ITG and ETG drive terms (a/LTi and a/LTe) within experimental error bars. The multi-scale simulations show for the first time that ETG streamers coexist and nonlinearly couple with ITG and zonal flows. This nonlinear cross-scale coupling enhances both ion and <span class="hlt">electron</span> heat <span class="hlt">fluxes</span> by up to a factor of 10 above standard, long wavelength simulation, resulting in simulations that simultaneously match experimental ion and <span class="hlt">electron</span> heat <span class="hlt">fluxes</span> and <span class="hlt">electron</span> profile stiffness. The new physics of ITG/ETG/zonal flow coupling has important implications for predictions of ITER performance and may be linked to phenomena such as confinement transitions and rotation reversals. This work was supported by DOE contract - DE-FC02-99ER54512-CMOD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JEMat..44.1116V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JEMat..44.1116V"><span>Solder <span class="hlt">Flux</span> Residues and Humidity-Related Failures in <span class="hlt">Electronics</span>: Relative Effects of Weak Organic Acids Used in No-Clean <span class="hlt">Flux</span> Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Verdingovas, Vadimas; Jellesen, Morten Stendahl; Ambat, Rajan</p> <p>2015-04-01</p> <p>This paper presents the results of humidity testing of weak organic acids (WOAs), namely adipic, succinic, glutaric, dl-malic, and palmitic acids, which are commonly used as activators in no-clean solder <span class="hlt">fluxes</span>. The study was performed under humidity conditions varying from 60% relative humidity (RH) to ˜99%RH at 25°C. The following parameters were used for characterization of WOAs: mass gain due to water adsorption and deliquescence of the WOA (by quartz crystal microbalance), resistivity of the water layer formed on the printed circuit board (by impedance spectroscopy), and leakage current measured using the surface insulation resistance pattern in the potential range from 0 V to 10 V. The combined results indicate the importance of the WOA chemical structure for the water adsorption and therefore conductive water layer formation on the printed circuit board assembly (PCBA). A substantial increase of leakage currents and probability of electrochemical migration was observed at humidity levels above the RH corresponding to the deliquescence point of WOAs present as contaminants on the printed circuit boards. The results suggest that use of solder <span class="hlt">fluxes</span> with WOAs having higher deliquescence point could improve the reliability of <span class="hlt">electronics</span> operating under circumstances in which exposure to high humidity is likely to occur.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1981seus.proc..189P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1981seus.proc..189P"><span><span class="hlt">Electron</span> content modeling - The significance of protonospheric contents and apparent <span class="hlt">fluxes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poulter, E. M.; Hargreaves, J. K.; Bailey, G. J.; Moffett, R. J.</p> <p></p> <p>A time-dependent model of the plasmasphere and the separation of TEC obtained from group delay measurements are studied. Temporal variations of the protonospheric content are interpreted as equivalent <span class="hlt">fluxes</span>, and the physical validity of the deduced quantities are investigated using a generalized model in which integration of the time dependent continuity and momentum equations along selected L-shells yields the ion densities and <span class="hlt">fluxes</span>. The shape parameters simulated by the equinox model agree by day, although night model values show discrepancies. Residual content is interpreted as the slant H(+) content beyond 2500 km, with the validity depending on the location of the receiving station and the state of the plasmasphere. The rate of change of residual content may be interpreted as a proton <span class="hlt">flux</span>, although the method is not valid for sudden perturbations, and the recovery of Np approaches that for <span class="hlt">flux</span> tubes with L values slightly greater than the minimum crossed for the three ray paths considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1786m0002S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1786m0002S"><span>Crossed contributions to <span class="hlt">electron</span> and heavy-particle transport <span class="hlt">fluxes</span> for magnetized plasmas in the continuum regime</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scoggins, James B.; Knisely, Carleton P.; Magin, Thierry E.</p> <p>2016-11-01</p> <p>We propose a unified fluid model for multicomponent plasmas in thermal nonequilibrium accounting for the influence of the electromagnetic field. In a previous work, this model was derived from kinetic theory based on a generalized Chapman-Enskog perturbative solution of the Boltzmann equation, scaled using the ratio of <span class="hlt">electron</span> to heavy-particle masses. Anisotropic transport properties were derived in terms of bracket integrals. In this work, explicit expressions for asymptotic solutions of the transport properties are derived using a spectral Galerkin projection supplied with Laguerre-Sonine polynomial basis functions, and we analyze the crossed contributions to <span class="hlt">electron</span> and heavy particle mass and energy <span class="hlt">fluxes</span>, known as the Kolesnikov effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA102905','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA102905"><span>Approximate Analytic Solutions for the Primary Auroral <span class="hlt">Electron</span> <span class="hlt">Flux</span> and Related Quantities.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1981-03-03</p> <p>Preliminary Remarks 18 8.2 Unidirectional- Monoenergetic Incident <span class="hlt">Flux</span> 19 8.3 Isotropic-Maxwellian Incident <span class="hlt">Flux</span> 20 8.4 Isotropic- Monoenergetic Incident...PSEUDOPARTICLES To APPROXIMATE THE SUMS 25 51 Contents 11. COMPARISONS 28 11. 1 Preliminary Remarks 28 11. 2 Comparisons for Isotropic - Monoenerget ie...the Analytic, Range, and Rees Models for 10, 5, and 2 KeV Isotrqpic- Monoenergetic Sources Each Containing 1 erg/cm s 30 6. Incident Maxwellian Energy</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22436618','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22436618"><span>The mechanism of chemisorption of hydrogen atom on graphene: Insights from the reaction force and reaction <span class="hlt">electronic</span> <span class="hlt">flux</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cortés-Arriagada, Diego Gutiérrez-Oliva, Soledad; Herrera, Bárbara; Soto, Karla; Toro-Labbé, Alejandro</p> <p>2014-10-07</p> <p>At the PBE-D3/cc-pVDZ level of theory, the hydrogen chemisorption on graphene was analyzed using the reaction force and reaction <span class="hlt">electronic</span> <span class="hlt">flux</span> (REF) theories in combination with <span class="hlt">electron</span> population analysis. It was found that chemisorption energy barrier is mainly dominated by structural work (∼73%) associated to the substrate reconstruction whereas the <span class="hlt">electronic</span> work is the greatest contribution of the reverse energy barrier (∼67%) in the desorption process. Moreover, REF shows that hydrogen chemisorption is driven by charge transfer processes through four <span class="hlt">electronic</span> events taking place as H approaches the adsorbent surface: (a) intramolecular charge transfer in the adsorbent surface; (b) surface reconstruction; (c) substrate magnetization and adsorbent carbon atom develops a sp{sup 3} hybridization to form the σC-H bond; and (d) spontaneous intermolecular charge transfer to reach the final chemisorbed state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27761802','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27761802"><span>Contribution of <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 promoter methylation in OSCC development.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ladiz, Mohammad Ayoub Rigi; Najafi, Maryam; Kordi-Tamandani, Dor Mohammad</p> <p>2017-03-01</p> <p>The aberrant DNA methylation of the tumor suppressor genes involved in DNA Damage Response (DDR) signaling and cell cycle regulation may lead to the tumorigenesis. Our purpose here is to analyze the promoter methylation and mRNA expression levels of <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 (<span class="hlt">LATS</span>1/2) genes in OSCC. Promoter methylation status of <span class="hlt">LATS</span>1/2 genes was evaluated in 70 OSCC paraffin-embedded tissues and 70 normal oral samples, using Methylation Specific PCR (MSP). <span class="hlt">LATS</span>1/2 mRNA expression profiles were also investigated in 14 OSCC patients and 14 normal samples, using real-time PCR. In both candidate genes, promoter methylation assessment revealed significant relationship between cases and controls (OR = 2.24, 95 % CI = 1.40-3.54, P = 0.001; <span class="hlt">LATS</span>1 and OR = 15.5, 95%CI = 3.64-64.76, P < 0.001; <span class="hlt">LATS</span>2). As well as, the evaluation of mRNA expression levels showed decreased expression in OSCC tissues in compare to control tissues. (Mean ± SD 1.74 ± 0.14 in OSCC versus 2.10 ± 0.24 in controls, P < 0.001; <span class="hlt">LATS</span>1 and Mean ± SD 1.36 ± 0.077 in OSCC versus 1.96 ± 0.096 in controls, P < 0.001; <span class="hlt">LATS</span>2). To the best our knowledge, this is the first report regarding the down-regulation of <span class="hlt">LATS</span>1/2 through promoter methylation in OSCC. It is suggested to explore the down-stream transcription factors of both genes for finding the molecular mechanism of this deregulation in OSCC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PPCF...57k5011P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PPCF...57k5011P"><span>Bi-Maxwellian <span class="hlt">electron</span> energy distribution function in the vicinity of the last closed <span class="hlt">flux</span> surface in fusion plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Popov, T. S. V. K.; Dimitrova, M.; Pedrosa, M. A.; López-Bruna, D.; Horacek, J.; Kovačič, J.; Dejarnac, R.; Stöckel, J.; Aftanas, M.; Böhm, P.; Bílková, P.; Hidalgo, C.; Panek, R.</p> <p>2015-11-01</p> <p>The first-derivative probe technique was applied to derive data for plasma parameters from the IV Langmuir probe characteristics measured in the plasma boundary region in the COMPASS tokamak and in the TJ-II stellarator. It is shown that in the COMPASS tokamak in the vicinity of the last closed <span class="hlt">flux</span> surface (LCFS) the <span class="hlt">electron</span> energy distribution function (EEDF) is bi-Maxwellian with the low-temperature <span class="hlt">electron</span> fraction predominating over the higher temperature one, whereas in the far scrape-off layer (SOL) the EEDF is Maxwellian. In the TJ-II stellarator during NBI heated plasma the EEDF in the confined plasma and close to the LCFS is bi-Maxwellian while in the far SOL the EEDF is Maxwellian. In contrast, during the ECR heating phase of the discharge both in the confined plasma and in the SOL the EEDF is bi-Maxwellian. The mechanism for the appearance of a bi-Maxwellian EEDF in the vicinity of the LCFS is discussed. The comparison of the results from probe measurements with ASTRA package and EIRENE code calculations suggests that the main reason of the appearance of a bi-Maxwellian EEDF in the vicinity of the LCFS is the ionization of the neutral atoms. Results for the <span class="hlt">electron</span> temperatures and densities obtained by the first-derivative probe technique in the COMPASS tokamak and in the TJ-II stellarator were used to evaluate the radial distribution of the parallel power <span class="hlt">flux</span> density. It is shown that in the SOL the radial distribution of the parallel power <span class="hlt">flux</span> density is a double exponential. It is pointed out that in the calculations of the parallel power <span class="hlt">flux</span> density at the LCFS the energy losses from ionization mechanisms must be taken into account.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..APR.K6004J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..APR.K6004J"><span>Fermi <span class="hlt">LAT</span> Limits on Primordial Black Hole Evaporation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Johnson, Chistian; Malyshev, Dmitry; Funk, Stefan; Ritz, Steven; Fermi LAT Collaboration</p> <p>2017-01-01</p> <p>Primordial black holes (PBHs) of sufficiently small mass emit gamma rays in the Fermi Large Area Telescope (<span class="hlt">LAT</span>) energy range. PBHs with lifetimes shorter than the Fermi observation time will appear as moving point sources with gamma-ray emission that becomes harder and brighter with time until the PBH completely evaporates. Previous searches for gamma rays from PBHs have focused on either short time scale bursts or the contribution of PBH bursts to the isotropic diffuse emission. Here we use Fermi <span class="hlt">LAT</span> point source catalogs to search for PBH candidates that evaporate on a time scale of several years. In addition to looking for the spectral signatures of a PBH, we also develop an algorithm to detect proper motion. There are a few unassociated point sources with spectra consistent with PBH evaporation; however, none of these sources show significant proper motion. We derive a conservative limit on PBH evaporation rate in the vicinity of the Earth by using a threshold on the gamma-ray <span class="hlt">flux</span> above 10 GeV such that there are no sources above this threshold with spectra consistent with Hawking radiation from PBHs. The derived limit is more stringent than the limits obtained with ground-based gamma-ray observatories.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357514-detection-small-magellanic-cloud-gamma-rays-fermi-lat','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357514-detection-small-magellanic-cloud-gamma-rays-fermi-lat"><span>Detection of the Small Magellanic Cloud in gamma-rays with  Fermi /<span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Abdo, A. A.</p> <p>2010-11-01</p> <p>Context. The <span class="hlt">flux</span> of gamma rays with energies greater than 100 MeV is dominated by diffuse emission coming from cosmic-rays (CRs) illuminating the interstellar medium (ISM) of our Galaxy through the processes of Bremsstrahlung, pion production and decay, and inverse-Compton scattering. The study of this diffuse emission provides insight into the origin and transport of cosmic rays. Aims. We searched for gamma-ray emission from the Small Magellanic Cloud (SMC) in order to derive constraints on the cosmic-ray population and transport in an external system with properties different from the Milky Way. Methods. We analysed the first 17 months of continuousmore » all-sky observations by the Large Area Telescope (<span class="hlt">LAT</span>) of the Fermi mission to determine the spatial distribution, <span class="hlt">flux</span> and spectrum of the gamma-ray emission from the SMC. We also used past radio synchrotron observations of the SMC to study the population of CR <span class="hlt">electrons</span> specifically. Results. We obtained the first detection of the SMC in high-energy gamma rays, with an integrated >100 MeV <span class="hlt">flux</span> of (3.7 ± 0.7) × 10-8 ph cm-2 s-1, with additional systematic uncertainty of ≤16%. The emission is steady and from an extended source ~3° in size. It is not clearly correlated with the distribution of massive stars or neutral gas, nor with known pulsars or supernova remnants, but a certain correlation with supergiant shells is observed. Conclusions. The observed <span class="hlt">flux</span> implies an upper limit on the average CR nuclei density in the SMC of ~15% of the value measured locally in the Milky Way. The population of high-energy pulsars of the SMC may account for a substantial fraction of the gamma-ray <span class="hlt">flux</span>, which would make the inferred CR nuclei density even lower. The average density of CR <span class="hlt">electrons</span> derived from radio synchrotron observations is consistent with the same reduction factor but the uncertainties are large. From our current knowledge of the SMC, such a low CR density does not seem to be due to a lower rate of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010A%26A...523A..46A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010A%26A...523A..46A"><span>Detection of the Small Magellanic Cloud in gamma-rays with Fermi/<span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abdo, A. A.; Ackermann, M.; Ajello, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bouvier, A.; Brandt, T. J.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Carrigan, S.; Casandjian, J. M.; Cecchi, C.; Çelik, Ö.; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Dermer, C. D.; de Palma, F.; Digel, S. W.; Silva, E. Do Couto E.; Drell, P. S.; Dubois, R.; Dumora, D.; Favuzzi, C.; Fegan, S. J.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Grondin, M.-H.; Grove, J. E.; Guiriec, S.; Hadasch, D.; Harding, A. K.; Hayashida, M.; Hays, E.; Horan, D.; Hughes, R. E.; Jean, P.; Jóhannesson, G.; Johnson, A. S.; Johnson, W. N.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kerr, M.; Knödlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S.-H.; Lemoine-Goumard, M.; Llena Garde, M.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Makeev, A.; Martin, P.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nakamori, T.; Naumann-Godo, M.; Nolan, P. L.; Norris, J. P.; Nuss, E.; Ohsugi, T.; Okumura, A.; Omodei, N.; Orlando, E.; Ormes, J. F.; Panetta, J. H.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Porter, T. A.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; Ripken, J.; Ritz, S.; Romani, R. W.; Sadrozinski, H. F.-W.; Sander, A.; Saz Parkinson, P. M.; Scargle, J. D.; Sgrò, C.; Siskind, E. J.; Smith, D. A.; Smith, P. D.; Spandre, G.; Spinelli, P.; Strickman, M. S.; Strong, A. W.; Suson, D. J.; Takahashi, H.; Takahashi, T.; Tanaka, T.; Thayer, J. B.; Thayer, J. G.; Thompson, D. J.; Tibaldo, L.; Torres, D. F.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vilchez, N.; Vitale, V.; Waite, A. P.; Wang, P.; Winer, B. L.; Wood, K. S.; Yang, Z.; Ylinen, T.; Ziegler, M.</p> <p>2010-11-01</p> <p>Context. The <span class="hlt">flux</span> of gamma rays with energies greater than 100 MeV is dominated by diffuse emission coming from cosmic-rays (CRs) illuminating the interstellar medium (ISM) of our Galaxy through the processes of Bremsstrahlung, pion production and decay, and inverse-Compton scattering. The study of this diffuse emission provides insight into the origin and transport of cosmic rays. Aims: We searched for gamma-ray emission from the Small Magellanic Cloud (SMC) in order to derive constraints on the cosmic-ray population and transport in an external system with properties different from the Milky Way. Methods: We analysed the first 17 months of continuous all-sky observations by the Large Area Telescope (<span class="hlt">LAT</span>) of the Fermi mission to determine the spatial distribution, <span class="hlt">flux</span> and spectrum of the gamma-ray emission from the SMC. We also used past radio synchrotron observations of the SMC to study the population of CR <span class="hlt">electrons</span> specifically. Results: We obtained the first detection of the SMC in high-energy gamma rays, with an integrated >100 MeV <span class="hlt">flux</span> of (3.7±0.7) × 10-8 ph cm-2 s-1, with additional systematic uncertainty of ≤16%. The emission is steady and from an extended source ~3° in size. It is not clearly correlated with the distribution of massive stars or neutral gas, nor with known pulsars or supernova remnants, but a certain correlation with supergiant shells is observed. Conclusions: The observed <span class="hlt">flux</span> implies an upper limit on the average CR nuclei density in the SMC of ~15% of the value measured locally in the Milky Way. The population of high-energy pulsars of the SMC may account for a substantial fraction of the gamma-ray <span class="hlt">flux</span>, which would make the inferred CR nuclei density even lower. The average density of CR <span class="hlt">electrons</span> derived from radio synchrotron observations is consistent with the same reduction factor but the uncertainties are large. From our current knowledge of the SMC, such a low CR density does not seem to be due to a lower rate of CR</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100031209','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100031209"><span>Fermi <span class="hlt">LAT</span> Results and Perspectives in Measurements of High Energy Galactic Cosmic Rays</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Moiseev, Alexander</p> <p>2010-01-01</p> <p>Real breakthrough during last 1-1.5 years in cosmic ray <span class="hlt">electrons</span>: ATIC, HESS, Pamela, and finally Fermi-<span class="hlt">LAT</span>. New quality data have made it possible to start quantitative modeling. With the new data more puzzles than before on CR <span class="hlt">electrons</span> origin. Need "multi-messenger" campaign: <span class="hlt">electrons</span>, positrons, gammas, X-ray, radio, neutrino... It is viable that we are dealing with at least two distinct mechanisms of "primary" <span class="hlt">electron</span> (both signs) production: a softer spectrum of negative <span class="hlt">electrons</span>, and a harder spectrum of both e(+)+e(-). Exotic (e.g. DM) origin is not ruled out. Upper limits on CR <span class="hlt">electrons</span> anisotropy are set. Good perspectives to have the Fermi <span class="hlt">LAT</span> results on proton spectrum and positron fraction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995PhRvB..51..381J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995PhRvB..51..381J"><span>Spin <span class="hlt">flux</span> and magnetic solitons in an interacting two-dimensional <span class="hlt">electron</span> gas: Topology of two-valued wave functions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>John, Sajeev; Golubentsev, Andrey</p> <p>1995-01-01</p> <p>It is suggested that an interacting many-<span class="hlt">electron</span> system in a two-dimensional lattice may condense into a topological magnetic state distinct from any discussed previously. This condensate exhibits local spin-1/2 magnetic moments on the lattice sites but is composed of a Slater determinant of single-<span class="hlt">electron</span> wave functions which exist in an orthogonal sector of the <span class="hlt">electronic</span> Hilbert space from the sector describing traditional spin-density-wave or spiral magnetic states. These one-<span class="hlt">electron</span> spinor wave functions have the distinguishing property that they are antiperiodic along a closed path encircling any elementary plaquette of the lattice. This corresponds to a 2π rotation of the internal coordinate frame of the <span class="hlt">electron</span> as it encircles the plaquette. The possibility of spinor wave functions with spatial antiperiodicity is a direct consequence of the two-valuedness of the internal <span class="hlt">electronic</span> wave function defined on the space of Euler angles describing its spin. This internal space is the topologically, doubly-connected, group manifold of SO(3). Formally, these antiperiodic wave functions may be described by passing a <span class="hlt">flux</span> which couples to spin (rather than charge) through each of the elementary plaquettes of the lattice. When applied to the two-dimensional Hubbard model with one <span class="hlt">electron</span> per site, this new topological magnetic state exhibits a relativistic spectrum for charged, quasiparticle excitations with a suppressed one-<span class="hlt">electron</span> density of states at the Fermi level. For a topological antiferromagnet on a square lattice, with the standard Hartree-Fock, spin-density-wave decoupling of the on-site Hubbard interaction, there is an exact mapping of the low-energy one-<span class="hlt">electron</span> excitation spectrum to a relativistic Dirac continuum field theory. In this field theory, the Dirac mass gap is precisely the Mott-Hubbard charge gap and the continuum field variable is an eight-component Dirac spinor describing the components of physical <span class="hlt">electron</span>-spin amplitude on each of</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22068828','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22068828"><span>Hot-<span class="hlt">electron</span> production and suprathermal heat <span class="hlt">flux</span> scaling with laser intensity from the two-plasmon-decay instability</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vu, H. X.; DuBois, D. F.; Myatt, J. F.; Russell, D. A.</p> <p>2012-10-15</p> <p>The fully kinetic reduced-description particle-in-cell (RPIC) method has been applied to simulations of two-plasmon-decay (TPD) instability, driven by crossed laser beams, in an inhomogeneous plasma for parameters consistent with recent direct-drive experiments related to laser-driven inertial fusion. The nonlinear saturated state is characterized by very spiky electric fields, with Langmuir cavitation occurring preferentially inside density channels produced by the ponderomotive beating of the crossed laser beams and the primary TPD Langmuir waves (LWs). The heated <span class="hlt">electron</span> distribution function is, in all cases, bi-Maxwellian, with instantaneous hot-<span class="hlt">electron</span> temperatures in the range 60-100 keV. The net hot-<span class="hlt">electron</span> energy <span class="hlt">flux</span> out of the system is a small fraction ({approx}1% to 2%) of the input laser intensity in these simulations. Scalings of the hot-<span class="hlt">electron</span> temperature and suprathermal heat <span class="hlt">flux</span> as functions of the laser intensity are obtained numerically from RPIC simulations. These simulations lead to the preliminary conclusion that Langmuir cavitation and collapse provide dissipation by producing suprathermal <span class="hlt">electrons</span>, which stabilize the system in saturation and drive the LW spectrum to the small dissipation scales at the Landau cutoff. The Langmuir turbulence originates at an <span class="hlt">electron</span> density 0.241 Multiplication-Sign the laser's critical density, where the crossed laser beams excite a 'triad' mode-a common forward LW plus a pair of backward LWs. Remnants of this 'triad' evolve in k-space and dominate the time-averaged energy spectrum. At times exceeding 10 ps, the excited Langmuir turbulence spreads toward lower densities. Comparisons of RPIC simulations with the extended Zakharov model are presented in appropriate regimes, and the necessary requirements for the validity of a quasi-linear Zakharov model (where the spatially averaged <span class="hlt">electron</span>-velocity distribution is evolved) are verified by RPIC simulation results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NucFu..57b2009A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NucFu..57b2009A"><span>Gyrokinetic study of turbulent convection of heavy impurities in tokamak plasmas at comparable ion and <span class="hlt">electron</span> heat <span class="hlt">fluxes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Angioni, C.; Bilato, R.; Casson, F. J.; Fable, E.; Mantica, P.; Odstrcil, T.; Valisa, M.; ASDEX Upgrade Team; Contributors, JET</p> <p>2017-02-01</p> <p>In tokamaks, the role of turbulent transport of heavy impurities, relative to that of neoclassical transport, increases with increasing size of the plasma, as clarified by means of general scalings, which use the ITER standard scenario parameters as reference, and by actual results from a selection of discharges from ASDEX Upgrade and JET. This motivates the theoretical investigation of the properties of the turbulent convection of heavy impurities by nonlinear gyrokinetic simulations in the experimentally relevant conditions of comparable ion and <span class="hlt">electron</span> heat <span class="hlt">fluxes</span>. These conditions also correspond to an intermediate regime between dominant ion temperature gradient turbulence and trapped <span class="hlt">electron</span> mode turbulence. At moderate plasma toroidal rotation, the turbulent convection of heavy impurities, computed with nonlinear gyrokinetic simulations, is found to be directed outward, in contrast to that obtained by quasi-linear calculations based on the most unstable linear mode, which is directed inward. In this mixed turbulence regime, with comparable <span class="hlt">electron</span> and ion heat <span class="hlt">fluxes</span>, the nonlinear results of the impurity transport can be explained by the coexistence of both ion temperature gradient and trapped <span class="hlt">electron</span> modes in the turbulent state, both contributing to the turbulent convection and diffusion of the impurity. The impact of toroidal rotation on the turbulent convection is also clarified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1304819-improved-empirical-model-electron-ion-fluxes-geosynchronous-orbit-based-upstream-solar-wind-conditions','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1304819-improved-empirical-model-electron-ion-fluxes-geosynchronous-orbit-based-upstream-solar-wind-conditions"><span>An improved empirical model of <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit based on upstream solar wind conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Denton, M. H.; Henderson, M. G.; Jordanova, V. K.; ...</p> <p>2016-07-01</p> <p>In this study, a new empirical model of the <span class="hlt">electron</span> <span class="hlt">fluxes</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit (GEO) is introduced, based on observations by Los Alamos National Laboratory (LANL) satellites. The model provides <span class="hlt">flux</span> predictions in the energy range ~1 eV to ~40 keV, as a function of local time, energy, and the strength of the solar wind electric field (the negative product of the solar wind speed and the z component of the magnetic field). Given appropriate upstream solar wind measurements, the model provides a forecast of the <span class="hlt">fluxes</span> at GEO with a ~1 h lead time. Model predictionsmore » are tested against in-sample observations from LANL satellites and also against out-of-sample observations from the Compact Environmental Anomaly Sensor II detector on the AMC-12 satellite. The model does not reproduce all structure seen in the observations. However, for the intervals studied here (quiet and storm times) the normalized root-mean-square deviation < ~0.3. It is intended that the model will improve forecasting of the spacecraft environment at GEO and also provide improved boundary/input conditions for physical models of the magnetosphere.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1304819','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1304819"><span>An improved empirical model of <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit based on upstream solar wind conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Denton, M. H.; Henderson, M. G.; Jordanova, V. K.; Thomsen, M. F.; Borovsky, J. E.; Woodroffe, J.; Hartley, D. P.; Pitchford, D.</p> <p>2016-07-01</p> <p>In this study, a new empirical model of the <span class="hlt">electron</span> <span class="hlt">fluxes</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit (GEO) is introduced, based on observations by Los Alamos National Laboratory (LANL) satellites. The model provides <span class="hlt">flux</span> predictions in the energy range ~1 eV to ~40 keV, as a function of local time, energy, and the strength of the solar wind electric field (the negative product of the solar wind speed and the z component of the magnetic field). Given appropriate upstream solar wind measurements, the model provides a forecast of the <span class="hlt">fluxes</span> at GEO with a ~1 h lead time. Model predictions are tested against in-sample observations from LANL satellites and also against out-of-sample observations from the Compact Environmental Anomaly Sensor II detector on the AMC-12 satellite. The model does not reproduce all structure seen in the observations. However, for the intervals studied here (quiet and storm times) the normalized root-mean-square deviation < ~0.3. It is intended that the model will improve forecasting of the spacecraft environment at GEO and also provide improved boundary/input conditions for physical models of the magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1304819','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1304819"><span>An improved empirical model of <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit based on upstream solar wind conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Denton, M. H.; Henderson, M. G.; Jordanova, V. K.; Thomsen, M. F.; Borovsky, J. E.; Woodroffe, J.; Hartley, D. P.; Pitchford, D.</p> <p>2016-07-01</p> <p>In this study, a new empirical model of the <span class="hlt">electron</span> <span class="hlt">fluxes</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit (GEO) is introduced, based on observations by Los Alamos National Laboratory (LANL) satellites. The model provides <span class="hlt">flux</span> predictions in the energy range ~1 eV to ~40 keV, as a function of local time, energy, and the strength of the solar wind electric field (the negative product of the solar wind speed and the z component of the magnetic field). Given appropriate upstream solar wind measurements, the model provides a forecast of the <span class="hlt">fluxes</span> at GEO with a ~1 h lead time. Model predictions are tested against in-sample observations from LANL satellites and also against out-of-sample observations from the Compact Environmental Anomaly Sensor II detector on the AMC-12 satellite. The model does not reproduce all structure seen in the observations. However, for the intervals studied here (quiet and storm times) the normalized root-mean-square deviation < ~0.3. It is intended that the model will improve forecasting of the spacecraft environment at GEO and also provide improved boundary/input conditions for physical models of the magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SpWea..14..511D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SpWea..14..511D"><span>An improved empirical model of <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit based on upstream solar wind conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Denton, M. H.; Henderson, M. G.; Jordanova, V. K.; Thomsen, M. F.; Borovsky, J. E.; Woodroffe, J.; Hartley, D. P.; Pitchford, D.</p> <p>2016-07-01</p> <p>A new empirical model of the <span class="hlt">electron</span> <span class="hlt">fluxes</span> and ion <span class="hlt">fluxes</span> at geosynchronous orbit (GEO) is introduced, based on observations by Los Alamos National Laboratory (LANL) satellites. The model provides <span class="hlt">flux</span> predictions in the energy range ~1 eV to ~40 keV, as a function of local time, energy, and the strength of the solar wind electric field (the negative product of the solar wind speed and the z component of the magnetic field). Given appropriate upstream solar wind measurements, the model provides a forecast of the <span class="hlt">fluxes</span> at GEO with a ~1 h lead time. Model predictions are tested against in-sample observations from LANL satellites and also against out-of-sample observations from the Compact Environmental Anomaly Sensor II detector on the AMC-12 satellite. The model does not reproduce all structure seen in the observations. However, for the intervals studied here (quiet and storm times) the normalized root-mean-square deviation < ~0.3. It is intended that the model will improve forecasting of the spacecraft environment at GEO and also provide improved boundary/input conditions for physical models of the magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..APR.J5003C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..APR.J5003C"><span>Searches for Angular Extension in High Latitude Fermi-<span class="hlt">LAT</span> Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caputo, Regina; di Mauro, Mattia; Meyer, Manuel; Wells, Brendan; Wood, Matthew; Fermi-LAT Collaboration</p> <p>2017-01-01</p> <p>We present a comprehensive search for angular extension in high-latitude gamma-ray sources detected by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) using the 4-year <span class="hlt">LAT</span> Point Source Catalog (3FGL). The majority of high-latitude <span class="hlt">LAT</span> sources are extragalactic blazars that appear point-like within the <span class="hlt">LAT</span> angular resolution. However, there are physics scenarios that predict populations of spatially extended sources. In one scenario, <span class="hlt">electron</span>-positron pair cascades from gamma rays produced in blazars are deflected in the Intergalactic Magnetic Field (IGMF) producing extended emission, or ``pair halos''. The detection of a pair halo component around a <span class="hlt">LAT</span>-detected blazar would provide a measurement of the strength and coherence length scale of the IGMF. In another scenario, the annihilation or decay of Weakly Interacting Massive Particles, a candidate for dark matter (DM), in Milky Way subhalos would appear as a population of unassociated gamma-ray sources with an angular extension. The detection of spatial extension in nearby sub halos could provide compelling evidence for a DM interpretation and would serve as an independent cross-check against other DM searches. We report on the angular extension catalog based on 7.5 years of Pass 8 data and discuss the implications of these results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009cxo..prop.2921C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009cxo..prop.2921C"><span>Identifying Unidentified Fermi-<span class="hlt">LAT</span> Objects (UFOs) at High-Latitude</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheung, Chi Teddy</p> <p>2009-09-01</p> <p>We propose a Chandra study of 8 high Galactic latitude gamma-ray sources in the Fermi-<span class="hlt">LAT</span> bright source list. These sources are currently unidentified, i.e., they are not clearly associated with established classes of gamma-ray emitters like blazars and pulsars. The proposed observations will determine the basic properties (<span class="hlt">fluxes</span>, positions, hardness ratio/spectra) of all X-ray sources down to a 0.3-10 keV <span class="hlt">flux</span> limit of 1.5e-14 erg/cm2/s within the Fermi-<span class="hlt">LAT</span> localization circles. This will enable further follow-up at other wavelengths, with the ultimate goal to reveal the nature of these enigmatic gamma-ray sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.7175....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.7175....1C"><span>Fermi-<span class="hlt">LAT</span> detection of hard spectrum gamma-ray activity from the FSRQ PKS 1532+01</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ciprini, S.; Cheung, C. C.</p> <p>2015-03-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> and an unusually hard gamma-ray spectrum from a source positionally consistent with the flat spectrum radio quasar (FSRQ) PKS 1532+01 (also known as 3FGL J1534.5+0128, Acero et al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.7545....1B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.7545....1B"><span>ATel 7545: Fermi <span class="hlt">LAT</span> Detection of a GeV flare from spectrally hard FSRQ S4 1800+44</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buson, S.; Fermi LAT Collaboration</p> <p>2015-05-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> and an unusually hard gamma-ray spectrum from a source positionally consistent with the flat spectrum radio quasar (FSRQ) S4 1800+44 (also known as 3FGL J1801.5+4403, Acero et al. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810038140&hterms=Borg+scale&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBorg%2Bscale','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810038140&hterms=Borg+scale&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBorg%2Bscale"><span>Decrease of keV <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> in the dayside magnetosphere during the early phase of magnetospheric disturbances</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hultqvist, B.; Aparicio, B.; Borg, H.; Arnoldy, R.; Moore, T. E.</p> <p>1981-01-01</p> <p>It is shown that a decrease of the keV particle <span class="hlt">fluxes</span> in the dayside magnetosphere near the geosynchronous orbit is characteristic of the first several hours of magnetospheric disturbances. After some hours newly injected plasma from the nightside reaches the 'evacuated' regions of the dayside magnetosphere and strong <span class="hlt">flux</span> increases are observed. The 'evacuation' of the dayside magnetosphere is interpreted in terms of a change in the convection pattern associated with an increase of the large scale electric field at the onset of the disturbance. The model presented is capable of accommodating all characteristics of the observational data, such as the temporal and spatial distributions, energy and pitch angle characteristics, and differences between <span class="hlt">electrons</span> and protons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810038140&hterms=Aparicio&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DAparicio','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810038140&hterms=Aparicio&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DAparicio"><span>Decrease of keV <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> in the dayside magnetosphere during the early phase of magnetospheric disturbances</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hultqvist, B.; Aparicio, B.; Borg, H.; Arnoldy, R.; Moore, T. E.</p> <p>1981-01-01</p> <p>It is shown that a decrease of the keV particle <span class="hlt">fluxes</span> in the dayside magnetosphere near the geosynchronous orbit is characteristic of the first several hours of magnetospheric disturbances. After some hours newly injected plasma from the nightside reaches the 'evacuated' regions of the dayside magnetosphere and strong <span class="hlt">flux</span> increases are observed. The 'evacuation' of the dayside magnetosphere is interpreted in terms of a change in the convection pattern associated with an increase of the large scale electric field at the onset of the disturbance. The model presented is capable of accommodating all characteristics of the observational data, such as the temporal and spatial distributions, energy and pitch angle characteristics, and differences between <span class="hlt">electrons</span> and protons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ATel.2026....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ATel.2026....1C"><span>Fermi <span class="hlt">LAT</span> detection of a GeV flare from blazar B2 1520+31</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cutini, S.; Hays, E.</p> <p>2009-04-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope (formerly GLAST, launched June 11, 2008), has observed an increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with B2 1520+31 (RA: 15 22 09.99 , Dec: +31 44 14.4 , J2000, A. J. Beasley et al. 2002, ApJS, 41, 13) since April 20, 2009.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ATel.5477....1B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ATel.5477....1B"><span>Fermi <span class="hlt">LAT</span> Detection of Renewed Activity from B2 2308+34</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buson, S.</p> <p>2013-10-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the Flat Spectrum Radio Quasar B2 2308+34 (R.A.=23:11:05.3288 Dec.=+34:25:10.905, J2000.0; z=1.817, Wills & Wills 1976, ApJS, 31,143).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008094','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008094"><span>Fermi-<span class="hlt">LAT</span> Observations of Galactic Transients</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hays, Elizabeth</p> <p>2011-01-01</p> <p>This slide presentation reviews the observations of Galactic transients by the Large Area Telescope (<span class="hlt">LAT</span>) on the Fermi Gamma Ray Space Telescope. The <span class="hlt">LAT</span> is producing spectacular results for the GeV transient sky, some of which are shown and reviewed. Some of the results in the GeV range that are discussed in this presentation are: (1) New blazars and unidentified transients (2) the jet of the Cygnus X-3 microquasar (3) gamma rays from V407 Cygni nova (4) Fast high-energy gamma-ray flares from the Crab Nebula</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4951031','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4951031"><span><span class="hlt">LATS</span>2 Positively Regulates Polycomb Repressive Complex 2</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Torigata, Kosuke; Daisuke, Okuzaki; Mukai, Satomi; Hatanaka, Akira; Ohka, Fumiharu; Motooka, Daisuke; Nakamura, Shota; Ohkawa, Yasuyuki; Yabuta, Norikazu; Kondo, Yutaka; Nojima, Hiroshi</p> <p>2016-01-01</p> <p><span class="hlt">LATS</span>2, a pivotal Ser/Thr kinase of the Hippo pathway, plays important roles in many biological processes. <span class="hlt">LATS</span>2 also function in Hippo-independent pathway, including mitosis, DNA damage response and epithelial to mesenchymal transition. However, the physiological relevance and molecular basis of these <span class="hlt">LATS</span>2 functions remain obscure. To understand novel functions of <span class="hlt">LATS</span>2, we constructed a <span class="hlt">LATS</span>2 knockout HeLa-S3 cell line using TAL-effector nuclease (TALEN). Integrated omics profiling of this cell line revealed that <span class="hlt">LATS</span>2 knockout caused genome-wide downregulation of Polycomb repressive complex 2 (PRC2) and H3K27me3. Cell-cycle analysis revealed that downregulation of PRC2 was not due to cell cycle aberrations caused by <span class="hlt">LATS</span>2 knockout. Not <span class="hlt">LATS</span>1, a homolog of <span class="hlt">LATS</span>2, but <span class="hlt">LATS</span>2 bound PRC2 on chromatin and phosphorylated it. <span class="hlt">LATS</span>2 positively regulates histone methyltransferase activity of PRC2 and their expression at both the mRNA and protein levels. Our findings reveal a novel signal upstream of PRC2, and provide insight into the crucial role of <span class="hlt">LATS</span>2 in coordinating the epigenome through regulation of PRC2. PMID:27434182</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM32A..08B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM32A..08B"><span>Prediction of Ultra-Relativistic <span class="hlt">Electron</span> <span class="hlt">Flux</span> Dynamics Through a Fusion of Machine-Learning and Physics-Based Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bortnik, J.; Ma, Q.; Chu, X.; Li, W.; Zhang, X.; Thorne, R. M.; Kletzing, C.; Hospodarsky, G. B.; Spence, H. E.; Reeves, G. D.; Kanekal, S. G.; Baker, D. N.</p> <p>2016-12-01</p> <p>The Earth's radiation belts are comprised of energetic <span class="hlt">electrons</span> with typical energies that are in the relativistic (>0.5 MeV) and ultra-relativistic range (>5 MeV or so). These radiation belts are a known hazard for spacecraft and hence represent an important societal concern, but they are also very interesting scientifically in that the processes that control the dynamics of the radiation belts are not fully understood. Typical approaches for predicting radiation belt dynamics involve either (1) physics-based modeling which requires global and time-dependent specification of boundary conditions and input parameters that are not always available, or (2) statistical predictive modeling which does not rely on a physics model, but requires a highly oversampled data set (i.e., large quantities of data) for accurate specification. When dealing with the ultra-relativistic range of <span class="hlt">electron</span> <span class="hlt">fluxes</span>, observations become sparse and predictive models become truly data starved so machine-learning techniques cannot be used directly. In this talk, we present a fusion between machine-learned models that specify the input parameters from a data-rich environment of lower-energy <span class="hlt">electrons</span> and waves, and a physics-based model that is able to dynamically use these inputs and calculate the <span class="hlt">fluxes</span> in the ultra-relativistic regime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22228038','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22228038"><span>Dense plasma heating and Gbar shock formation by a high intensity <span class="hlt">flux</span> of energetic <span class="hlt">electrons</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ribeyre, X.; Feugeas, J.-L.; Nicolaï, Ph.; Tikhonchuk, V. T.; Gus'kov, S.</p> <p>2013-06-15</p> <p>Process of shock ignition in inertial confinement fusion implies creation of a high pressure shock with a laser spike having intensity of the order of a few PW/cm{sup 2}. However, the collisional (Bremsstrahlung) absorption at these intensities is inefficient and a significant part of laser energy is converted in a stream of energetic <span class="hlt">electrons</span>. The process of shock formation in a dense plasma by an intense <span class="hlt">electron</span> beam is studied in this paper in a planar geometry. The energy deposition takes place in a fixed mass target layer with the areal density determined by the <span class="hlt">electron</span> range. A self-similar isothermal rarefaction wave of a fixed mass describes the expanding plasma. Formation of a shock wave in the target under the pressure of expanding plasma is described. The efficiency of <span class="hlt">electron</span> beam energy conversion into the shock wave energy depends on the fast <span class="hlt">electron</span> energy and the pulse duration. The model is applied to the laser produced fast <span class="hlt">electrons</span>. The fast <span class="hlt">electron</span> energy transport could be the dominant mechanism of ablation pressure creation under the conditions of shock ignition. The shock wave pressure exceeding 1 Gbar during 200–300 ps can be generated with the <span class="hlt">electron</span> pulse intensity in the range of 5–10 PW/cm{sup 2}. The conclusions of theoretical model are confirmed in numerical simulations with a radiation hydrodynamic code coupled with a fast <span class="hlt">electron</span> transport module.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/881125','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/881125"><span>The GLAST Mission, <span class="hlt">LAT</span> and GRBs</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Omodei, Nicola; /INFN, Pisa</p> <p>2006-04-05</p> <p>The GLAST Large Area Telescope (<span class="hlt">LAT</span>) is the next generation satellite experiment for high-energy gamma-ray astronomy. It is a pair conversion telescope built with a plastic anticoincidence shield, a segmented CsI electromagnetic calorimeter, and the largest silicon strip tracker ever built. It will cover the energy range from 30 MeV to 300 GeV, shedding light on many issues left open by its predecessor EGRET. One of the most exciting science topics is the detection and observation of gamma-ray bursts (GRBs). In this paper we present the work done so far by the GRB <span class="hlt">LAT</span> science group in studying the performance of the <span class="hlt">LAT</span> detector to observe GRBs.We report on the simulation framework developed by the group as well as on the science tools dedicated to GRBs data analysis. We present the <span class="hlt">LAT</span> sensitivity to GRBs obtained with such simulations, and, finally, the general scheme of GRBs detection that will be adopted on orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.457L..99P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.457L..99P"><span>The Fermi-<span class="hlt">LAT</span> view of the colliding wind binaries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pshirkov, M. S.</p> <p>2016-03-01</p> <p>Colliding wind binaries (CWBs) have been considered as a possible high-energy γ-ray sources for some time, however no system other than η Car has been detected. In the Letter, a sample of seven CWBs (WR 11, WR 70, WR 137, WR 140, WR 146, WR 147) which, by means of theoretic modelling, were deemed most promising candidates, was analysed using almost 7 yr of the Fermi-Large Area Telescope (<span class="hlt">LAT</span>) data. WR 11 (γ2 Vel) was detected at 6.1σ confidence level with a photon <span class="hlt">flux</span> in 0.1-100 GeV range (1.8 ± 0.6) × 10-9 ph cm-2 s-1 and an energy <span class="hlt">flux</span> (2.7 ± 0.5) × 10-12 erg cm-2 s-1. At the adopted distance d = 340 pc this corresponds to a luminosity L = (3.7 ± 0.7) × 1031 erg s-1. This luminosity amounts to ˜6 × 10-6 fraction of the total wind kinetic power and ˜1.6 × 10-4 fraction of the power injected into the wind-wind interaction region of this system. Upper limits were set on the high energy <span class="hlt">flux</span> from the WR 70 and WR 140 systems.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6854009','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6854009"><span>Critical heat <span class="hlt">flux</span> investigations for fusion-relevant conditions with the use of a rastered <span class="hlt">electron</span> beam apparatus</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Koski, J.A.; Croessmann, C.D.</p> <p>1988-01-01</p> <p>With the use of a rastered <span class="hlt">electron</span> beam apparatus, investigations of critical heat <span class="hlt">flux</span> (CH) and associated noise, pressure and flow spectra have been completed for water-cooled test targets under conditions relevant to the design of high-heat-<span class="hlt">flux</span> components for fusion energy applications. Targets tested were copper tubes with attached graphite armor tiles. Water flows with velocities ranging from 3 to 10 m/s were used, with axially uniform heat <span class="hlt">fluxes</span> ranging from 10 to 60 MW/m/sup 2/ applied along only one side of the tube to simulate the heating pattern often encountered by plasma facing components in fusion applications. Targets included stainless steel twisted tapes mechanically locked into the tube bore to increase CH levels. Exit conditions typical of highly subcooled flow boiling were considered, e.g., exit qualities of about /minus/0.3, with exit pressures near 1 MPa, and exit temperatures in the 30 to 40 C range. Besides observation of CHF and the comparison to CHF correlations, the studies also examined possible means for predicting and preventing tube burnout. Diagnostics tried included acoustic amplitude and spectra in both the audible and above audible frequency ranges, exit pressure amplitude and spectra, and flow variations and spectra. During testing, signals from the diagnostics showed a large increase in amplitude before CHF occurred. 13 refs., 9 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355678-fermi-lat-observations-high-energy-gamma-ray-emission-toward-galactic-center','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355678-fermi-lat-observations-high-energy-gamma-ray-emission-toward-galactic-center"><span>Fermi-<span class="hlt">LAT</span> Observations of High-Energy Gamma-Ray Emission Toward the Galactic Center</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ajello, M.</p> <p>2016-02-26</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has provided the most detailed view to date of the emission towards the Galactic centre (GC) in high-energy γ-rays. This paper describes the analysis of data taken during the first 62 months of the mission in the energy range 1 - 100 GeV from a 15° X15° region about the direction of the GC, and implications for the interstellar emissions produced by cosmic ray (CR) particles interacting with the gas and radiation fields in the inner Galaxy and for the point sources detected. Specialised interstellar emission models (IEMs) are constructed that enable separation ofmore » the γ-ray emission from the inner ~ 1 kpc about the GC from the fore- and background emission from the Galaxy. Based on these models, the interstellar emission from CR <span class="hlt">electrons</span> interacting with the interstellar radiation field via the inverse Compton (IC) process and CR nuclei inelastically scattering off the gas producing γ-rays via π⁰ decays from the inner ~ 1 kpc is determined. The IC contribution is found to be dominant in the region and strongly enhanced compared to previous studies. A catalog of point sources for the 15 °X 15 °region is self-consistently constructed using these IEMs: the First Fermi–<span class="hlt">LAT</span> Inner Galaxy point source Catalog (1FIG). The spatial locations, <span class="hlt">fluxes</span>, and spectral properties of the 1FIG sources are presented, and compared with γ-ray point sources over the same region taken from existing catalogs, including the Third Fermi–<span class="hlt">LAT</span> Source Catalog (3FGL). In general, the spatial density of 1FIG sources differs from those in the 3FGL, which is attributed to the different treatments of the interstellar emission and energy ranges used by the respective analyses. Three 1FIG sources are found to spatially overlap with supernova remnants (SNRs) listed in Green’s SNR catalog; these SNRs have not previously been associated with high-energy γ-ray sources. Most 3FGL sources with known multi-wavelength counterparts are also found</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1355678','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1355678"><span>Fermi-<span class="hlt">LAT</span> Observations of High-Energy Gamma-Ray Emission Toward the Galactic Center</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ajello, M.</p> <p>2016-02-26</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has provided the most detailed view to date of the emission towards the Galactic centre (GC) in high-energy γ-rays. This paper describes the analysis of data taken during the first 62 months of the mission in the energy range 1 - 100 GeV from a 15° X15° region about the direction of the GC, and implications for the interstellar emissions produced by cosmic ray (CR) particles interacting with the gas and radiation fields in the inner Galaxy and for the point sources detected. Specialised interstellar emission models (IEMs) are constructed that enable separation of the γ-ray emission from the inner ~ 1 kpc about the GC from the fore- and background emission from the Galaxy. Based on these models, the interstellar emission from CR <span class="hlt">electrons</span> interacting with the interstellar radiation field via the inverse Compton (IC) process and CR nuclei inelastically scattering off the gas producing γ-rays via π⁰ decays from the inner ~ 1 kpc is determined. The IC contribution is found to be dominant in the region and strongly enhanced compared to previous studies. A catalog of point sources for the 15 °X 15 °region is self-consistently constructed using these IEMs: the First Fermi–<span class="hlt">LAT</span> Inner Galaxy point source Catalog (1FIG). The spatial locations, <span class="hlt">fluxes</span>, and spectral properties of the 1FIG sources are presented, and compared with γ-ray point sources over the same region taken from existing catalogs, including the Third Fermi–<span class="hlt">LAT</span> Source Catalog (3FGL). In general, the spatial density of 1FIG sources differs from those in the 3FGL, which is attributed to the different treatments of the interstellar emission and energy ranges used by the respective analyses. Three 1FIG sources are found to spatially overlap with supernova remnants (SNRs) listed in Green’s SNR catalog; these SNRs have not previously been associated with high-energy γ-ray sources. Most 3FGL sources with known multi-wavelength counterparts are also found. However</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21057313','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21057313"><span><span class="hlt">LAT</span> Automated Science Processing for Gamma-Ray Bursts</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chiang, James</p> <p>2007-05-01</p> <p>The <span class="hlt">LAT</span> Instrument Science Operations Center (ISOC) will perform various tasks to support coordination of multiwavelength observations for transient sources. In this paper, we describe the prototype implementation of the Automated Science Processing (ASP) for the detection and analysis of gamma-ray bursts (GRBs) in <span class="hlt">LAT</span> and GBM data. The GRB-related tasks include: position refinement using <span class="hlt">LAT</span> data given initial GBM or GCN locations, spectral analysis using <span class="hlt">LAT</span> data alone, joint spectral fitting with GBM data, gamma-ray afterglow detection and characterization, and blind searches for prompt burst emission in <span class="hlt">LAT</span> data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSM24B..05O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSM24B..05O"><span>Formation Process of Relativistic <span class="hlt">Electron</span> <span class="hlt">Flux</span> Through Interaction with Chorus Emissions in the Earth's Inner Magnetosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Omura, Y.; Miyashita, Y.; Yoshikawa, M.; Summers, D.; Hikishima, M.; Ebihara, Y.; Kubota, Y.</p> <p>2015-12-01</p> <p>We perform test particle simulations of energetic <span class="hlt">electrons</span> interacting with whistler-mode chorus emissions. We compute trajectories of a large number of <span class="hlt">electrons</span> forming a delta function with the same energy and pitch angle. The <span class="hlt">electrons</span> are launched at different locations along the magnetic field line and different timings with respect to a pair of chorus emissions generated at the magnetic equator. We follow the evolution of the delta function, and obtain a distribution function in energy and equatorial pitch angle, which is a numerical Green's function for one cycle of chorus wave-particle interaction. We obtain the Green's functions for the energy range 10 keV ˜ 6 MeV and all pitch angles greater than the loss cone angle. By taking the convolution integral of the Green's functions with the distribution function of the injected <span class="hlt">electrons</span> repeatedly, we follow a long-time evolution of the distribution function. We find that the energetic <span class="hlt">electrons</span> are accelerated effectively by relativistic turning acceleration and ultra-relativistic acceleration through nonlinear trapping by chorus emissions, and that these processes result in the rapid formation of a dumbbell distribution of highly relativistic <span class="hlt">electrons</span> within a few minutes after the injection of tens of keV <span class="hlt">electrons</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22865398','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22865398"><span><span class="hlt">Electronic</span> <span class="hlt">fluxes</span> during Diels-Alder reactions involving 1,2-benzoquinones: mechanistic insights from the analysis of <span class="hlt">electron</span> localization function and catastrophe theory.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>González-Navarrete, Patricio; Domingo, Luis R; Andrés, Juan; Berski, Slawomir; Silvi, Bernard</p> <p>2012-11-15</p> <p>By means of the joint use of <span class="hlt">electron</span> localization function (ELF) and Thom's catastrophe theory, a theoretical analysis of the energy profile for the hetero-Diels-Alder reaction of 4-methoxy-1,2-benzoquinone 1 and methoxyethylene 2 has been carried out. The 12 different structural stability domains obtained by the bonding evolution theory have been identified as well as the bifurcation catastrophes (fold and cusp) responsible for the changes in the topology of the system. This analysis permits finding a relationship between the ELF topology and the evolution of the bond breaking/forming processes and <span class="hlt">electron</span> pair rearrangements through the reaction progress in terms of the different ways of pairing up the <span class="hlt">electrons</span>. The reaction mechanism corresponds to an asynchronous <span class="hlt">electronic</span> <span class="hlt">flux</span>; first, the O1-C5 bond is formed by the nucleophilic attack of the C5 carbon of the <span class="hlt">electron</span> rich ethylene 2 on the most electrophilically activated carbonyl O1 oxygen of 1, and once the σ bond has been completed, the formation process of the second O4C6 bond takes place. In addition, the values of the local electrophilicity and local nucleophilcity indices in the framework of conceptual density functional theory accounts for the asychronicity of the process as well as for the observed regioselectivity. Copyright © 2012 Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003APh....20..195K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003APh....20..195K"><span>Limits on the ultra-high energy <span class="hlt">electron</span> neutrino <span class="hlt">flux</span> from the RICE experiment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kravchenko, I.; Frichter, G. M.; Miller, T.; Piccirillo, L.; Seckel, D.; Spiczak, G. M.; Adams, J.; Seunarine, S.; Allen, C.; Bean, A.; Besson, D.; Box, D. J.; Buniy, R.; Drees, J.; McKay, D.; Meyers, J.; Perry, L.; Ralston, J.; Razzaque, S.; Schmitz, D. W.</p> <p>2003-11-01</p> <p>Upper limits are presented on the diffuse <span class="hlt">flux</span> of ultra-high energy νe, based on analysis of data taken by the RICE experiment during August, 2000. The RICE receiver array at South Pole monitors cold ice for radio-wavelength Cherenkov radiation resulting from neutrino induced in-ice showers. For energies above 1 EeV, RICE is an effective detector of over 15 km 3 sr. Potential signal events are separated from backgrounds using vertex location, event reconstruction, and signal shape. These are the first terrestrial limits exploiting the physics of radio-Cherenkov emissions from charged current νe+ N→e+ N' interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22133848','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22133848"><span>MULTIWAVELENGTH OBSERVATIONS AND MODELING OF 1ES 1959+650 IN A LOW <span class="hlt">FLUX</span> STATE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Aliu, E.; Errando, M.; Archambault, S.; Arlen, T.; Aune, T.; Beilicke, M.; Bugaev, V.; Dickherber, R.; Benbow, W.; Bird, R.; Collins-Hughes, E.; Boettcher, M.; Bouvier, A.; Byrum, K.; Cesarini, A.; Connolly, M. P.; Ciupik, L.; Cui, W.; Duke, C.; Dumm, J.; and others</p> <p>2013-09-20</p> <p>We report on the VERITAS observations of the high-frequency peaked BL Lac object 1ES 1959+650 in the period 2007-2011. This source is detected at TeV energies by VERITAS at 16.4 standard deviation ({sigma}) significance in 7.6 hr of observation in a low <span class="hlt">flux</span> state. A multiwavelength spectral energy distribution (SED) is constructed from contemporaneous data from VERITAS, Fermi-<span class="hlt">LAT</span>, RXTE PCA, and Swift UVOT. Swift XRT data is not included in the SED due to a lack of simultaneous observations with VERITAS. In contrast to the orphan {gamma}-ray flare exhibited by this source in 2002, the X-ray <span class="hlt">flux</span> of the source is found to vary by an order of magnitude, while other energy regimes exhibit less variable emission. A quasi-equilibrium synchrotron self-Compton model with an additional external radiation field is used to describe three SEDs corresponding to the lowest, highest, and average X-ray states. The variation in the X-ray spectrum is modeled by changing the <span class="hlt">electron</span> injection spectral index, with minor adjustments of the kinetic luminosity in <span class="hlt">electrons</span>. This scenario produces small-scale <span class="hlt">flux</span> variability of the order of {approx}< 2 in the high energy (E > 1 MeV) and very high energy (E > 100 GeV) {gamma}-ray regimes, which is corroborated by the Fermi-<span class="hlt">LAT</span>, VERITAS, and Whipple 10 m telescope light curves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E2743R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E2743R"><span>The observations of <span class="hlt">fluxes</span> of relativistic <span class="hlt">electrons</span> at the latitudes of the auroral oval: results of METEOR-M No.1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Riazantseva, Maria; Antonova, Elizaveta; Marjin, Boris; Barinova, Vera; Myagkova, Irina</p> <p></p> <p>We analyze the simultaneous observations of the <span class="hlt">fluxes</span> of auroral <span class="hlt">electrons</span> and the <span class="hlt">fluxes</span> of relativistic <span class="hlt">electrons</span> at the external boundary of the outer <span class="hlt">electron</span> radiation belts using data of METEOR-M No1 satellite for the period from November 3, 2009 till April 30, 2010. The geomagnetic conditions during analyzed period were comparatively quite. METEOR-M No.1 has a polar solar-synchronous circular orbit with an altitude of ~832 km, a period of 101.3 min, and an inclination of 98.068 degrees. The <span class="hlt">electrons</span> with the energies from 0.1 to 13 MeV and protons from 1 to 260 MeV were measured by GGAK-M instrument composed by semiconductor and scintillator detectors. The plasma <span class="hlt">electrons</span> with the energies from 0.03 to 16 keV were measured by the segment electrostatic analyzer. The observation of <span class="hlt">fluxes</span> of relativistic <span class="hlt">electrons</span> were selected inside the auroral oval connected with the development of magnetospheric substorms. However, the <span class="hlt">fluxes</span> of relativistic <span class="hlt">electrons</span> are also observed during absolutely quite time intervals. We compare the obtained results with the observations of CORONAS-FOTON satellite demonstrating the quasistationary (for more than 3 hours) increases of relativistic <span class="hlt">electrons</span> at the latitudes of the auroral oval and argue that the processes inside the auroral oval can play the considerable role in the acceleration of relativistic <span class="hlt">electrons</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3925999','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3925999"><span>Fluctuations in the <span class="hlt">electron</span> system of a superconductor exposed to a photon <span class="hlt">flux</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>de Visser, P. J.; Baselmans, J. J. A.; Bueno, J.; Llombart, N.; Klapwijk, T. M.</p> <p>2014-01-01</p> <p>In a superconductor, in which <span class="hlt">electrons</span> are paired, the density of unpaired <span class="hlt">electrons</span> should become zero when approaching zero temperature. Therefore, radiation detectors based on breaking of pairs promise supreme sensitivity, which we demonstrate using an aluminium superconducting microwave resonator. Here we show that the resonator also enables the study of the response of the <span class="hlt">electron</span> system of the superconductor to pair-breaking photons, microwave photons and varying temperatures. A large range in radiation power (at 1.54 THz) can be chosen by carefully filtering the radiation from a blackbody source. We identify two regimes. At high radiation power, fluctuations in the <span class="hlt">electron</span> system caused by the random arrival rate of the photons are resolved, giving a straightforward measure of the optical efficiency (48±8%) and showing an unprecedented detector sensitivity. At low radiation power, fluctuations are dominated by excess quasiparticles, the number of which is measured through their recombination lifetime. PMID:24496036</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24496036','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24496036"><span>Fluctuations in the <span class="hlt">electron</span> system of a superconductor exposed to a photon <span class="hlt">flux</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>de Visser, P J; Baselmans, J J A; Bueno, J; Llombart, N; Klapwijk, T M</p> <p>2014-01-01</p> <p>In a superconductor, in which <span class="hlt">electrons</span> are paired, the density of unpaired <span class="hlt">electrons</span> should become zero when approaching zero temperature. Therefore, radiation detectors based on breaking of pairs promise supreme sensitivity, which we demonstrate using an aluminium superconducting microwave resonator. Here we show that the resonator also enables the study of the response of the <span class="hlt">electron</span> system of the superconductor to pair-breaking photons, microwave photons and varying temperatures. A large range in radiation power (at 1.54 THz) can be chosen by carefully filtering the radiation from a blackbody source. We identify two regimes. At high radiation power, fluctuations in the <span class="hlt">electron</span> system caused by the random arrival rate of the photons are resolved, giving a straightforward measure of the optical efficiency (48 ± 8%) and showing an unprecedented detector sensitivity. At low radiation power, fluctuations are dominated by excess quasiparticles, the number of which is measured through their recombination lifetime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4584955','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4584955"><span>Partially dissecting the steady-state <span class="hlt">electron</span> <span class="hlt">fluxes</span> in Photosystem I in wild-type and pgr5 and ndh mutants of Arabidopsis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kou, Jiancun; Takahashi, Shunichi; Fan, Da-Yong; Badger, Murray R.; Chow, Wah S.</p> <p>2015-01-01</p> <p>Cyclic <span class="hlt">electron</span> <span class="hlt">flux</span> (CEF) around Photosystem I (PS I) is difficult to quantify. We obtained the linear <span class="hlt">electron</span> <span class="hlt">flux</span> (LEFO2) through both photosystems and the total <span class="hlt">electron</span> <span class="hlt">flux</span> through PS I (ETR1) in Arabidopsis in CO2-enriched air. Δ<span class="hlt">Flux</span> = ETR1 – LEFO2 is an upper estimate of CEF, which consists of two components, an antimycin A-sensitive, PGR5 (proton gradient regulation 5 protein)-dependent component and an insensitive component facilitated by a chloroplastic nicotinamide adenine dinucleotide dehydrogenase-like complex (NDH). Using wild type as well as pgr5 and ndh mutants, we observed that (1) 40% of the absorbed light was partitioned to PS I; (2) at high irradiance a substantial antimycin A-sensitive CEF occurred in the wild type and the ndh mutant; (3) at low irradiance a sizable antimycin A-sensitive CEF occurred in the wild type but not in the ndh mutant, suggesting an enhancing effect of NDH in low light; and (4) in the pgr5 mutant, and the wild type and ndh mutant treated with antimycin A, a residual Δ<span class="hlt">Flux</span> existed at high irradiance, attributable to charge recombination and/or pseudo-cyclic <span class="hlt">electron</span> flow. Therefore, in low-light-acclimated plants exposed to high light, Δ<span class="hlt">Flux</span> has contributions from various paths of <span class="hlt">electron</span> flow through PS I. PMID:26442071</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JAP...120m4308O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JAP...120m4308O"><span>Crystallization of sputter-deposited amorphous Ge films by <span class="hlt">electron</span> irradiation: Effect of low-<span class="hlt">flux</span> pre-irradiation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Okugawa, M.; Nakamura, R.; Ishimaru, M.; Yasuda, H.; Numakura, H.</p> <p>2016-10-01</p> <p>We investigated the effect of low-<span class="hlt">flux</span> <span class="hlt">electron</span> irradiation with 125 keV to sputter-deposited amorphous germanium on the amorphous structure and <span class="hlt">electron</span>-induced crystallization microstructure by TEM following our previous study on the effect of aging at room temperature. In samples aged for 3 days, coarse, spherical particles about 100 nm in diameter appear dominantly. By low-<span class="hlt">flux</span> pre-irradiation to the samples, a reduction in the size and number of coarse particles, embedded in the matrix with fine nanograins of the diamond cubic structure, was noted with the increase in fluence. The crystal structure of these coarse particles was found to be not cubic but hexagonal. In samples aged for 4 months, a similar tendency was observed. In samples aged for 7 months, on the other hand, the homogeneous diamond cubic structured nanograins were unchanged by pre-irradiation. These results indicate that pre-irradiation as well as aging modifies the amorphous structure, preventing the appearance of a hexagonal phase. The elimination of a certain amount of medium-range ordered clusters by pre-irradiation, included in as-deposited samples and the samples aged for 4 months, apparently gives rise to a reduction in the size and number of coarse particles with a metastable hexagonal structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16732470','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16732470"><span>The ROS production induced by a reverse-<span class="hlt">electron</span> <span class="hlt">flux</span> at respiratory-chain complex 1 is hampered by metformin.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Batandier, Cécile; Guigas, Bruno; Detaille, Dominique; El-Mir, M-Yehia; Fontaine, Eric; Rigoulet, M; Leverve, Xavier M</p> <p>2006-02-01</p> <p>Mitochondrial reactive oxygen species (ROS) production was investigated in mitochondria extracted from liver of rats treated with or without metformin, a mild inhibitor of respiratory chain complex 1 used in type 2 diabetes. A high rate of ROS production, fully suppressed by rotenone, was evidenced in non-phosphorylating mitochondria in the presence of succinate as a single complex 2 substrate. This ROS production was substantially lowered by metformin pretreatment and by any decrease in membrane potential (Delta Phi(m)), redox potential (NADH/NAD), or phosphate potential, as induced by malonate, 2,4-dinitrophenol, or ATP synthesis, respectively. ROS production in the presence of glutamate-malate plus succinate was lower than in the presence of succinate alone, but higher than in the presence of glutamate-malate. Moreover, while rotenone both increased and decreased ROS production at complex 1 depending on forward (glutamate-malate) or reverse (succinate) <span class="hlt">electron</span> <span class="hlt">flux</span>, no ROS overproduction was evidenced in the forward direction with metformin. Therefore, we propose that reverse <span class="hlt">electron</span> <span class="hlt">flux</span> through complex 1 is an alternative pathway, which leads to a specific metformin-sensitive ROS production.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/918541','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/918541"><span>GLAST <span class="hlt">LAT</span> And Pulsars: What Do We Learn from Simulations?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Razzano, Massimiliano; Harding, Alice K.; /NASA, Goddard</p> <p>2007-10-24</p> <p>Gamma-ray pulsars are among the best targets for the Large Area Telescope (<span class="hlt">LAT</span>) aboard the GLAST mission. The higher sensitivity, time and energy resolution of the <span class="hlt">LAT</span> will provide data of fundamental importance to understand the physics of these fascinating objects. Powerful tools for studying the <span class="hlt">LAT</span> capabilities for pulsar science are the simulation programs developed within the GLAST Collaboration. Thanks to these simulations it is possible to produce a detailed distribution of gamma-ray photons in energy and phase that can be folded through the <span class="hlt">LAT</span> Instrument Response Functions (IRFs). Here we present some of the main interesting results from the simulations developed to study the discovery potential of the <span class="hlt">LAT</span>. In particular we will focus on the capability of the <span class="hlt">LAT</span> to discover new radio-loud gamma-ray pulsars, on the discrimination between Polar Cap and Outer Gap models, and on the <span class="hlt">LAT</span> pulsar sensitivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20610546','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20610546"><span>The <span class="hlt">LAT</span> story: a tale of cooperativity, coordination, and choreography.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Balagopalan, Lakshmi; Coussens, Nathan P; Sherman, Eilon; Samelson, Lawrence E; Sommers, Connie L</p> <p>2010-08-01</p> <p>The adapter molecule <span class="hlt">LAT</span> is a nucleating site for multiprotein signaling complexes that are vital for the function and differentiation of T cells. Extensive investigation of <span class="hlt">LAT</span> in multiple experimental systems has led to an integrated understanding of the formation, composition, regulation, dynamic movement, and function of <span class="hlt">LAT</span>-nucleated signaling complexes. This review discusses interactions of signaling molecules that bind directly or indirectly to <span class="hlt">LAT</span> and the role of cooperativity in stabilizing <span class="hlt">LAT</span>-nucleated signaling complexes. In addition, it focuses on how imaging studies visualize signaling assemblies as signaling clusters and demonstrate their dynamic nature and cellular fate. Finally, this review explores the function of <span class="hlt">LAT</span> based on the interpretation of mouse models using various <span class="hlt">LAT</span> mutants.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22482895','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22482895"><span>Investigation on the <span class="hlt">electron</span> <span class="hlt">flux</span> to the wall in the VENUS ion source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Thuillier, T. Angot, J.</p> <p>2016-02-15</p> <p>The long-term operation of high charge state <span class="hlt">electron</span> cyclotron resonance ion sources fed with high microwave power has caused damage to the plasma chamber wall in several laboratories. Porosity, or a small hole, can be progressively created in the chamber wall which can destroy the plasma chamber over a few year time scale. A burnout of the VENUS plasma chamber is investigated in which the hole formation in relation to the local hot <span class="hlt">electron</span> power density is studied. First, the results of a simple model assuming that hot <span class="hlt">electrons</span> are fully magnetized and strictly following magnetic field lines are presented. The model qualitatively reproduces the experimental traces left by the plasma on the wall. However, it is too crude to reproduce the localized <span class="hlt">electron</span> power density for creating a hole in the chamber wall. Second, the results of a Monte Carlo simulation, following a population of scattering hot <span class="hlt">electrons</span>, indicate a localized high power deposited to the chamber wall consistent with the hole formation process. Finally, a hypervapotron cooling scheme is proposed to mitigate the hole formation in <span class="hlt">electron</span> cyclotron resonance plasma chamber wall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016RScI...87bA736T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016RScI...87bA736T"><span>Investigation on the <span class="hlt">electron</span> <span class="hlt">flux</span> to the wall in the VENUS ion source</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thuillier, T.; Angot, J.; Benitez, J. Y.; Hodgkinson, A.; Lyneis, C. M.; Todd, D. S.; Xie, D. Z.</p> <p>2016-02-01</p> <p>The long-term operation of high charge state <span class="hlt">electron</span> cyclotron resonance ion sources fed with high microwave power has caused damage to the plasma chamber wall in several laboratories. Porosity, or a small hole, can be progressively created in the chamber wall which can destroy the plasma chamber over a few year time scale. A burnout of the VENUS plasma chamber is investigated in which the hole formation in relation to the local hot <span class="hlt">electron</span> power density is studied. First, the results of a simple model assuming that hot <span class="hlt">electrons</span> are fully magnetized and strictly following magnetic field lines are presented. The model qualitatively reproduces the experimental traces left by the plasma on the wall. However, it is too crude to reproduce the localized <span class="hlt">electron</span> power density for creating a hole in the chamber wall. Second, the results of a Monte Carlo simulation, following a population of scattering hot <span class="hlt">electrons</span>, indicate a localized high power deposited to the chamber wall consistent with the hole formation process. Finally, a hypervapotron cooling scheme is proposed to mitigate the hole formation in <span class="hlt">electron</span> cyclotron resonance plasma chamber wall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26931954','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26931954"><span>Investigation on the <span class="hlt">electron</span> <span class="hlt">flux</span> to the wall in the VENUS ion source.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thuillier, T; Angot, J; Benitez, J Y; Hodgkinson, A; Lyneis, C M; Todd, D S; Xie, D Z</p> <p>2016-02-01</p> <p>The long-term operation of high charge state <span class="hlt">electron</span> cyclotron resonance ion sources fed with high microwave power has caused damage to the plasma chamber wall in several laboratories. Porosity, or a small hole, can be progressively created in the chamber wall which can destroy the plasma chamber over a few year time scale. A burnout of the VENUS plasma chamber is investigated in which the hole formation in relation to the local hot <span class="hlt">electron</span> power density is studied. First, the results of a simple model assuming that hot <span class="hlt">electrons</span> are fully magnetized and strictly following magnetic field lines are presented. The model qualitatively reproduces the experimental traces left by the plasma on the wall. However, it is too crude to reproduce the localized <span class="hlt">electron</span> power density for creating a hole in the chamber wall. Second, the results of a Monte Carlo simulation, following a population of scattering hot <span class="hlt">electrons</span>, indicate a localized high power deposited to the chamber wall consistent with the hole formation process. Finally, a hypervapotron cooling scheme is proposed to mitigate the hole formation in <span class="hlt">electron</span> cyclotron resonance plasma chamber wall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11311135','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11311135"><span>Association of 4F2hc with light chains <span class="hlt">LAT</span>1, <span class="hlt">LAT</span>2 or y+<span class="hlt">LAT</span>2 requires different domains.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bröer, A; Friedrich, B; Wagner, C A; Fillon, S; Ganapathy, V; Lang, F; Bröer, S</p> <p>2001-05-01</p> <p>Heterodimeric amino acid transporters are comprised of a type-II membrane protein named the heavy chain (4F2hc or rBAT) that may associate with a number of different polytopic membrane proteins, called light chains. It is thought that the heavy chain is mainly involved in the trafficking of the complex to the plasma membrane, whereas the transport process itself is catalysed by the light chain. The 4F2 heavy chain (4F2hc) associates with at least six different light chains to induce distinct amino acid-transport activites. To test if the light chains are specifically recognized and to identify domains involved in the recognition of light chains, C-terminally truncated mutants of 4F2hc were constructed and co-expressed with the light chains <span class="hlt">LAT</span>1, <span class="hlt">LAT</span>2 and y(+)<span class="hlt">LAT</span>2. The truncated isoform T1, comprised of only 133 amino acids that form the cytosolic N-terminus and the transmembrane helix, displayed only a slight reduction in its ability to promote <span class="hlt">LAT</span>1 expression at the membrane surface compared with the 529 amino acid wild-type 4F2hc protein. Co-expression of increasingly larger 4F2hc mutants caused a delayed translocation of <span class="hlt">LAT</span>1. In contrast to the weak effects of 4F2hc truncations on <span class="hlt">LAT</span>1 expression, surface expression of <span class="hlt">LAT</span>2 and y(+)<span class="hlt">LAT</span>2 was almost completely lost with all truncated heavy chains. Co-expression of <span class="hlt">LAT</span>1 together with the other light chains did not result in displacement of <span class="hlt">LAT</span>2 and y(+)<span class="hlt">LAT</span>2. The results suggest that extracellular domains of the heavy chain are responsible mainly for recognition of light chains other than <span class="hlt">LAT</span>1 and that the extracellular domain ensures proper translocation to the plasma membrane.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1221788','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1221788"><span>Association of 4F2hc with light chains <span class="hlt">LAT</span>1, <span class="hlt">LAT</span>2 or y+<span class="hlt">LAT</span>2 requires different domains.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bröer, A; Friedrich, B; Wagner, C A; Fillon, S; Ganapathy, V; Lang, F; Bröer, S</p> <p>2001-01-01</p> <p>Heterodimeric amino acid transporters are comprised of a type-II membrane protein named the heavy chain (4F2hc or rBAT) that may associate with a number of different polytopic membrane proteins, called light chains. It is thought that the heavy chain is mainly involved in the trafficking of the complex to the plasma membrane, whereas the transport process itself is catalysed by the light chain. The 4F2 heavy chain (4F2hc) associates with at least six different light chains to induce distinct amino acid-transport activites. To test if the light chains are specifically recognized and to identify domains involved in the recognition of light chains, C-terminally truncated mutants of 4F2hc were constructed and co-expressed with the light chains <span class="hlt">LAT</span>1, <span class="hlt">LAT</span>2 and y(+)<span class="hlt">LAT</span>2. The truncated isoform T1, comprised of only 133 amino acids that form the cytosolic N-terminus and the transmembrane helix, displayed only a slight reduction in its ability to promote <span class="hlt">LAT</span>1 expression at the membrane surface compared with the 529 amino acid wild-type 4F2hc protein. Co-expression of increasingly larger 4F2hc mutants caused a delayed translocation of <span class="hlt">LAT</span>1. In contrast to the weak effects of 4F2hc truncations on <span class="hlt">LAT</span>1 expression, surface expression of <span class="hlt">LAT</span>2 and y(+)<span class="hlt">LAT</span>2 was almost completely lost with all truncated heavy chains. Co-expression of <span class="hlt">LAT</span>1 together with the other light chains did not result in displacement of <span class="hlt">LAT</span>2 and y(+)<span class="hlt">LAT</span>2. The results suggest that extracellular domains of the heavy chain are responsible mainly for recognition of light chains other than <span class="hlt">LAT</span>1 and that the extracellular domain ensures proper translocation to the plasma membrane. PMID:11311135</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5029684','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5029684"><span>An evolutionarily conserved negative feedback mechanism in the Hippo pathway reflects functional difference between <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Park, Gun-Soo; Oh, Hyangyee; Kim, Minchul; Kim, Tackhoon; Johnson, Randy L.; Irvine, Kenneth D.; Lim, Dae-Sik</p> <p>2016-01-01</p> <p>The Hippo pathway represses YAP oncoprotein activity through phosphorylation by <span class="hlt">LATS</span> kinases. Although variety of upstream components has been found to participate in the Hippo pathway, the existence and function of negative feedback has remained uncertain. We found that activated YAP, together with TEAD transcription factors, directly induces transcription of <span class="hlt">LATS</span>2, but not <span class="hlt">LATS</span>1, to form a negative feedback loop. We also observed increased mRNA levels of Hippo upstream components upon YAP activation. To reveal the physiological role of this negative feedback regulation, we deleted <span class="hlt">Lats</span>2 or <span class="hlt">Lats</span>1 in the liver-specific Sav1-knockout mouse model which develops a YAP-induced tumor. Additional deletion of <span class="hlt">Lats</span>2 severely enhanced YAP-induced tumorigenic phenotypes in a liver specific Sav1 knock-out mouse model while additional deletion of <span class="hlt">Lats</span>1 mildly affected the phenotype. Only Sav1 and <span class="hlt">Lats</span>2 double knock-down cells formed larger colonies in soft agar assay, thereby recapitulating accelerated tumorigenesis seen in vivo. Importantly, this negative feedback is evolutionarily conserved, as Drosophila Yorkie (YAP ortholog) induces transcription of Warts (<span class="hlt">LATS</span>2 ortholog) with Scalloped (TEAD ortholog). Collectively, we demonstrated the existence and function of an evolutionarily conserved negative feedback mechanism in the Hippo pathway, as well as the functional difference between <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 in regulation of YAP. PMID:27006470</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27006470','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27006470"><span>An evolutionarily conserved negative feedback mechanism in the Hippo pathway reflects functional difference between <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Park, Gun-Soo; Oh, Hyangyee; Kim, Minchul; Kim, Tackhoon; Johnson, Randy L; Irvine, Kenneth D; Lim, Dae-Sik</p> <p>2016-04-26</p> <p>The Hippo pathway represses YAP oncoprotein activity through phosphorylation by <span class="hlt">LATS</span> kinases. Although variety of upstream components has been found to participate in the Hippo pathway, the existence and function of negative feedback has remained uncertain. We found that activated YAP, together with TEAD transcription factors, directly induces transcription of <span class="hlt">LATS</span>2, but not <span class="hlt">LATS</span>1, to form a negative feedback loop. We also observed increased mRNA levels of Hippo upstream components upon YAP activation. To reveal the physiological role of this negative feedback regulation, we deleted <span class="hlt">Lats</span>2 or <span class="hlt">Lats</span>1 in the liver-specific Sav1-knockout mouse model which develops a YAP-induced tumor. Additional deletion of <span class="hlt">Lats</span>2 severely enhanced YAP-induced tumorigenic phenotypes in a liver specific Sav1 knock-out mouse model while additional deletion of <span class="hlt">Lats</span>1 mildly affected the phenotype. Only Sav1 and <span class="hlt">Lats</span>2 double knock-down cells formed larger colonies in soft agar assay, thereby recapitulating accelerated tumorigenesis seen in vivo. Importantly, this negative feedback is evolutionarily conserved, as Drosophila Yorkie (YAP ortholog) induces transcription of Warts (<span class="hlt">LATS</span>2 ortholog) with Scalloped (TEAD ortholog). Collectively, we demonstrated the existence and function of an evolutionarily conserved negative feedback mechanism in the Hippo pathway, as well as the functional difference between <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 in regulation of YAP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JVSJ...53..132W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JVSJ...53..132W"><span>Ion <span class="hlt">Flux</span> Impingement on the Cathode Surface in an Axisymmetric <span class="hlt">Electron</span> Gun</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watanabe, Masaya; Kusumoto, Yoshiro</p> <p></p> <p>The flow of the residual gas ion generated by a collision with high-energy <span class="hlt">electron</span> in an axisymmetric gun was numerically investigated. Since the lifetime of the gun is dominated by the cathode damage induced by the ion bombardment, it is of industrial importance to reveal how the ions impinge on the cathode and how the inflow can be repelled. Under the normal operating condition of the <span class="hlt">electron</span> gun (40 kV, 6 A), we determined the inflow basin, i.e. the region where the gas ions were born there and finally reached to the cathode. The basin consisted of four separated zones characterized by the potential distribution on the beam axis. To eliminate the downstream zones, it was useful to append a positive voltage imposed electrode behind the anode. The voltage necessary for repelling the ion inflow was found to be 300 V being less than 1% of the <span class="hlt">electron</span> acceleration voltage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1355684','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1355684"><span>Search for gamma-ray emission from the Coma Cluster with six years of Fermi-<span class="hlt">LAT</span> data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ackermann, M.</p> <p>2016-03-08</p> <p>We present results from γ-ray observations of the Coma cluster incorporating 6 years of Fermi-<span class="hlt">LAT</span> data and the newly released “Pass 8” event-level analysis. Our analysis of the region reveals low-significance residual structures within the virial radius of the cluster that are too faint for a detailed investigation with the current data. Using a likelihood approach that is free of assumptions on the spectral shape we derive upper limits on the γ-ray <span class="hlt">flux</span> that is expected from energetic particle interactions in the cluster. We also consider a benchmark spatial and spectral template motivated by models in which the observed radio halo is mostly emission by secondary <span class="hlt">electrons</span>. In this case, the median expected and observed upper limits for the <span class="hlt">flux</span> above 100MeV are 1.7 x 10<sup>-9</sup> ph cm<sup>-2</sup> s<sup>-1 </sup>and 5.2 x 10<sup>-9</sup> ph cm<sup>-2</sup> s<sup>-1</sup> respectively (the latter corresponds to residual emission at the level of 1:8σ). These bounds are comparable to or higher than predicted levels of hadronic gamma-ray emission in cosmic-ray models with or without reacceleration of secondary <span class="hlt">electrons</span>, although direct comparisons are sensitive to assumptions regarding the origin and propagation mode of cosmic rays and magnetic field properties. The minimal expected γ-ray <span class="hlt">flux</span> from radio and star-forming galaxies within the Coma cluster is roughly an order of magnitude below the median sensitivity of our analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355684-search-gamma-ray-emission-from-coma-cluster-six-years-fermi-lat-data','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355684-search-gamma-ray-emission-from-coma-cluster-six-years-fermi-lat-data"><span>Search for gamma-ray emission from the Coma Cluster with six years of Fermi-<span class="hlt">LAT</span> data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ackermann, M.</p> <p>2016-03-08</p> <p>We present results from γ-ray observations of the Coma cluster incorporating 6 years of Fermi-<span class="hlt">LAT</span> data and the newly released “Pass 8” event-level analysis. Our analysis of the region reveals low-significance residual structures within the virial radius of the cluster that are too faint for a detailed investigation with the current data. Using a likelihood approach that is free of assumptions on the spectral shape we derive upper limits on the γ-ray <span class="hlt">flux</span> that is expected from energetic particle interactions in the cluster. We also consider a benchmark spatial and spectral template motivated by models in which the observed radiomore » halo is mostly emission by secondary <span class="hlt">electrons</span>. In this case, the median expected and observed upper limits for the <span class="hlt">flux</span> above 100MeV are 1.7 x 10-9 ph cm-2 s-1 and 5.2 x 10-9 ph cm-2 s-1 respectively (the latter corresponds to residual emission at the level of 1:8σ). These bounds are comparable to or higher than predicted levels of hadronic gamma-ray emission in cosmic-ray models with or without reacceleration of secondary <span class="hlt">electrons</span>, although direct comparisons are sensitive to assumptions regarding the origin and propagation mode of cosmic rays and magnetic field properties. The minimal expected γ-ray <span class="hlt">flux</span> from radio and star-forming galaxies within the Coma cluster is roughly an order of magnitude below the median sensitivity of our analysis.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170003557&hterms=Fisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DFisica','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170003557&hterms=Fisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DFisica"><span>Search for Gamma-Ray Emission from the Coma Cluster with Six Years of Fermi-<span class="hlt">LAT</span> Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ackermann, M.; Ajello, M.; Albert, A.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170003557'); toggleEditAbsImage('author_20170003557_show'); toggleEditAbsImage('author_20170003557_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170003557_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170003557_hide"></p> <p>2016-01-01</p> <p>We present results from gamma-ray observations of the Coma cluster incorporating six years of Fermi-<span class="hlt">LAT</span> data and the newly released 'Pass 8' event-level analysis. Our analysis of the region reveals low-significance residual structures within the virial radius of the cluster that are too faint for a detailed investigation with the current data. Using a likelihood approach that is free of assumptions on the spectral shape we derive upper limits on the gamma-ray <span class="hlt">flux</span> that is expected from energetic particle interactions in the cluster. We also consider a benchmark spatial and spectral template motivated by models in which the observed radio halo is mostly emission by secondary <span class="hlt">electrons</span>. In this case, the median expected and observed upper limits for the <span class="hlt">flux</span> above 100 MeV are 1.7 x 10(exp -9) ph cm(exp -2) s(exp -1) and 5.2 x 10(exp -9) ph cm(exp -2) s(exp -1) respectively (the latter corresponds to residual emission at the level of 1.8sigma). These bounds are comparable to or higher than predicted levels of hadronic gamma-ray emission in cosmic-ray (CR) models with or without reacceleration of secondary <span class="hlt">electrons</span>, although direct comparisons are sensitive to assumptions regarding the origin and propagation mode of CRs and magnetic field properties. The minimal expected gamma-ray <span class="hlt">flux</span> from radio and star-forming galaxies within the Coma cluster is roughly an order of magnitude below the median sensitivity of our analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...819..149A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...819..149A"><span>Search for Gamma-Ray Emission from the Coma Cluster with Six Years of Fermi-<span class="hlt">LAT</span> Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ackermann, M.; Ajello, M.; Albert, A.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Bregeon, J.; Bruel, P.; Buehler, R.; Caliandro, G. A.; Cameron, R. A.; Caragiulo, M.; Caraveo, P. A.; Casandjian, J. M.; Cavazzuti, E.; Cecchi, C.; Charles, E.; Chekhtman, A.; Chiaro, G.; Ciprini, S.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Fegan, S. J.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giordano, F.; Giroletti, M.; Godfrey, G.; Green, D.; Grenier, I. A.; Guiriec, S.; Hays, E.; Hewitt, J. W.; Horan, D.; Jóhannesson, G.; Kuss, M.; Larsson, S.; Latronico, L.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Madejski, G. M.; Maldera, S.; Manfreda, A.; Mayer, M.; Mazziotta, M. N.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nuss, E.; Ohsugi, T.; Orienti, M.; Orlando, E.; Ormes, J. F.; Paneque, D.; Pesce-Rollins, M.; Petrosian, V.; Piron, F.; Pivato, G.; Porter, T. A.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Sánchez-Conde, M.; Sgrò, C.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Tajima, H.; Takahashi, H.; Thayer, J. B.; Tibaldo, L.; Torres, D. F.; Tosti, G.; Troja, E.; Vianello, G.; Wood, K. S.; Zimmer, S.; Fermi-LAT Collaboration; Rephaeli, Y.</p> <p>2016-03-01</p> <p>We present results from γ-ray observations of the Coma cluster incorporating six years of Fermi-<span class="hlt">LAT</span> data and the newly released “Pass 8” event-level analysis. Our analysis of the region reveals low-significance residual structures within the virial radius of the cluster that are too faint for a detailed investigation with the current data. Using a likelihood approach that is free of assumptions on the spectral shape we derive upper limits on the γ-ray <span class="hlt">flux</span> that is expected from energetic particle interactions in the cluster. We also consider a benchmark spatial and spectral template motivated by models in which the observed radio halo is mostly emission by secondary <span class="hlt">electrons</span>. In this case, the median expected and observed upper limits for the <span class="hlt">flux</span> above 100 {MeV} are 1.7 × 10-9 ph cm-2 s-1 and 5.2 × 10-9 ph cm-2 s-1 respectively (the latter corresponds to residual emission at the level of 1.8σ). These bounds are comparable to or higher than predicted levels of hadronic gamma-ray emission in cosmic-ray (CR) models with or without reacceleration of secondary <span class="hlt">electrons</span>, although direct comparisons are sensitive to assumptions regarding the origin and propagation mode of CRs and magnetic field properties. The minimal expected γ-ray <span class="hlt">flux</span> from radio and star-forming galaxies within the Coma cluster is roughly an order of magnitude below the median sensitivity of our analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NucFu..55a3015C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NucFu..55a3015C"><span>Dynamics of multiple <span class="hlt">flux</span> tubes in sawtoothing KSTAR plasmas heated by <span class="hlt">electron</span> cyclotron waves: I. Experimental analysis of the tube structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Choe, G. H.; Yun, G. S.; Nam, Y.; Lee, W.; Park, H. K.; Bierwage, A.; Domier, C. W.; Luhmann, N. C., Jr.; Jeong, J. H.; Bae, Y. S.; the KSTAR Team</p> <p>2015-01-01</p> <p>Multiple (two or more) <span class="hlt">flux</span> tubes are commonly observed inside and/or near the q = 1 <span class="hlt">flux</span> surface in KSTAR tokamak plasmas with localized <span class="hlt">electron</span> cyclotron resonance heating and current drive (ECH/CD). Detailed 2D and quasi-3D images of the <span class="hlt">flux</span> tubes obtained by an advanced imaging diagnostic system showed that the <span class="hlt">flux</span> tubes are m/n = 1/1 field-aligned structures co-rotating around the magnetic axis. The <span class="hlt">flux</span> tubes typically merge together and become like the internal kink mode of the usual sawtooth, which then collapses like a usual sawtooth crash. A systematic scan of ECH/CD beam position showed a strong correlation with the number of <span class="hlt">flux</span> tubes. In the presence of multiple <span class="hlt">flux</span> tubes close to the q = 1 surface, the radially outward heat transport was enhanced, which explains naturally temporal changes of <span class="hlt">electron</span> temperature. We emphasize that the multiple <span class="hlt">flux</span> tubes are a universal feature distinct from the internal kink instability and play a critical role in the control of sawteeth using ECH/CD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1357270','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1357270"><span>Fermi-<span class="hlt">LAT</span> Search for Pulsar Wind Nebulae around gamma-ray Pulsars</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ackermann, M.; Ajello, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bouvier, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Camilo, F.; Caraveo, P. A.; Casandjian, J. M.; Cecchi, C.; Çelik, Ö.; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiang, J.; Ciprini, S.; Claus, R.; Cognard, I.; Cohen-Tanugi, J.; Conrad, J.; Dermer, C. D.; de Angelis, A.; de Luca, A.; de Palma, F.; Digel, S. W.; do Couto e Silva, E.; Drell, P. S.; Dubois, R.; Dumora, D.; Favuzzi, C.; Focke, W. B.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Germani, S.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Grondin, M. -H.; Grove, J. E.; Guillemot, L.; Guiriec, S.; Hadasch, D.; Hanabata, Y.; Harding, A. K.; Hayashi, K.; Hays, E.; Hobbs, G.; Hughes, R. E.; Jóhannesson, G.; Johnson, A. S.; Johnson, W. N.; Johnston, S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Keith, M.; Kerr, M.; Knödlseder, J.; Kramer, M.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S. -H.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Lyne, A. G.; Makeev, A.; Marelli, M.; Mazziotta, M. N.; McEnery, J. E.; Mehault, J.; Michelson, P. F.; Mizuno, T.; Moiseev, A. A.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nakamori, T.; Naumann-Godo, M.; Nolan, P. L.; Noutsos, A.; Nuss, E.; Ohsugi, T.; Okumura, A.; Ormes, J. F.; Paneque, D.; Panetta, J. H.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Porter, T. A.; Rainò, S.; Rando, R.; Ransom, S. M.; Ray, P. S.; Razzano, M.; Rea, N.; Reimer, A.; Reimer, O.; Reposeur, T.; Ripken, J.; Ritz, S.; Romani, R. W.; Sadrozinski, H. F. -W.; Sander, A.; Parkinson, P. M. Saz; Sgrò, C.; Siskind, E. J.; Smith, D. A.; Smith, P. D.; Spandre, G.; Spinelli, P.; Strickman, M. S.; Suson, D. J.; Takahashi, H.; Takahashi, T.; Tanaka, T.; Thayer, J. B.; Thayer, J. G.; Theureau, G.; Thompson, D. J.; Thorsett, S. E.; Tibaldo, L.; Torres, D. F.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; Uehara, T.; Usher, T. L.; Vandenbroucke, J.; Van Etten, A.; Vasileiou, V.; Vilchez, N.; Vitale, V.; Waite, A. P.; Wang, P.; Weltevrede, P.; Winer, B. L.; Wood, K. S.; Yang, Z.; Ylinen, T.; Ziegler, M.</p> <p>2010-12-13</p> <p>The high sensitivity of the Fermi-<span class="hlt">LAT</span> (Large Area Telescope) offers the first opportunity to study faint and extended GeV sources such as pulsar wind nebulae (PWNe). After one year of observation the <span class="hlt">LAT</span> detected and identified three PWNe: the Crab Nebula, Vela-X, and the PWN inside MSH 15-52. In the meantime, the list of <span class="hlt">LAT</span> detected pulsars increased steadily. These pulsars are characterized by high energy loss rates ($\\dot{E}$) from ~3 × 10<sup>33</sup> erg s<sup>–1</sup> to 5 × 10<sup>38</sup> erg s<sup>–1</sup> and are therefore likely to power a PWN. This paper summarizes the search for PWNe in the off-pulse windows of 54 <span class="hlt">LAT</span>-detected pulsars using 16 months of survey observations. Ten sources show significant emission, seven of these likely being of magnetospheric origin. The detection of significant emission in the off-pulse interval offers new constraints on the γ-ray emitting regions in pulsar magnetospheres. The three other sources with significant emission are the Crab Nebula, Vela-X, and a new PWN candidate associated with the <span class="hlt">LAT</span> pulsar PSR J1023–5746, coincident with the TeV source HESS J1023–575. Here, we further explore the association between the HESS and the Fermi source by modeling its spectral energy distribution. Lastly, <span class="hlt">flux</span> upper limits derived for the 44 remaining sources are used to provide new constraints on famous PWNe that have been detected at keV and/or TeV energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357270-fermi-lat-search-pulsar-wind-nebulae-around-gamma-ray-pulsars','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357270-fermi-lat-search-pulsar-wind-nebulae-around-gamma-ray-pulsars"><span>Fermi-<span class="hlt">LAT</span> Search for Pulsar Wind Nebulae around gamma-ray Pulsars</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ackermann, M.; Ajello, M.; Baldini, L.; ...</p> <p>2010-12-13</p> <p>The high sensitivity of the Fermi-<span class="hlt">LAT</span> (Large Area Telescope) offers the first opportunity to study faint and extended GeV sources such as pulsar wind nebulae (PWNe). After one year of observation the <span class="hlt">LAT</span> detected and identified three PWNe: the Crab Nebula, Vela-X, and the PWN inside MSH 15-52. In the meantime, the list of <span class="hlt">LAT</span> detected pulsars increased steadily. These pulsars are characterized by high energy loss rates (more » $$\\dot{E}$$) from ~3 × 1033 erg s–1 to 5 × 1038 erg s–1 and are therefore likely to power a PWN. This paper summarizes the search for PWNe in the off-pulse windows of 54 <span class="hlt">LAT</span>-detected pulsars using 16 months of survey observations. Ten sources show significant emission, seven of these likely being of magnetospheric origin. The detection of significant emission in the off-pulse interval offers new constraints on the γ-ray emitting regions in pulsar magnetospheres. The three other sources with significant emission are the Crab Nebula, Vela-X, and a new PWN candidate associated with the <span class="hlt">LAT</span> pulsar PSR J1023–5746, coincident with the TeV source HESS J1023–575. Here, we further explore the association between the HESS and the Fermi source by modeling its spectral energy distribution. Lastly, <span class="hlt">flux</span> upper limits derived for the 44 remaining sources are used to provide new constraints on famous PWNe that have been detected at keV and/or TeV energies.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21567713','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21567713"><span>FERMI-<span class="hlt">LAT</span> SEARCH FOR PULSAR WIND NEBULAE AROUND GAMMA-RAY PULSARS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Bloom, E. D.; Borgland, A. W.; Bouvier, A.; Buehler, R.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Ballet, J.; Bastieri, D.; Buson, S.; Bonamente, E.; Brigida, M.; Bruel, P.</p> <p>2011-01-01</p> <p>The high sensitivity of the Fermi-<span class="hlt">LAT</span> (Large Area Telescope) offers the first opportunity to study faint and extended GeV sources such as pulsar wind nebulae (PWNe). After one year of observation the <span class="hlt">LAT</span> detected and identified three PWNe: the Crab Nebula, Vela-X, and the PWN inside MSH 15-52. In the meantime, the list of <span class="hlt">LAT</span> detected pulsars increased steadily. These pulsars are characterized by high energy loss rates ( E-dot ) from {approx}3 x 10{sup 33} erg s{sup -1} to 5 x 10{sup 38} erg s{sup -1} and are therefore likely to power a PWN. This paper summarizes the search for PWNe in the off-pulse windows of 54 <span class="hlt">LAT</span>-detected pulsars using 16 months of survey observations. Ten sources show significant emission, seven of these likely being of magnetospheric origin. The detection of significant emission in the off-pulse interval offers new constraints on the {gamma}-ray emitting regions in pulsar magnetospheres. The three other sources with significant emission are the Crab Nebula, Vela-X, and a new PWN candidate associated with the <span class="hlt">LAT</span> pulsar PSR J1023-5746, coincident with the TeV source HESS J1023-575. We further explore the association between the HESS and the Fermi source by modeling its spectral energy distribution. <span class="hlt">Flux</span> upper limits derived for the 44 remaining sources are used to provide new constraints on famous PWNe that have been detected at keV and/or TeV energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhLA..381.3066C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhLA..381.3066C"><span>Geodesic mode instability driven by <span class="hlt">electron</span> and ion <span class="hlt">fluxes</span> during neutral beam injection in tokamaks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Camilo de Souza, F.; Elfimov, A. G.; Galvão, R. M. O.; Krbec, J.; Seidl, J.; Stöckel, J.; Hron, M.; Havlicek, J.; Mitosinkova, K.</p> <p>2017-09-01</p> <p>The effect of a minor concentration of energetic particles produced by parallel NB injection on Geodesic Acoustic Modes (GAM) spectrum is analyzed using fully kinetic equation. It is found that the GAM frequency is reduced by the effective mass renormalization due to that new energetic GAM appears with higher frequency. The <span class="hlt">electron</span> current in combination with NB driven ion flow, modeled by shifted Maxwell distribution, may overcome the ion Landau damping thus resulting in the GAM instability when <span class="hlt">electron</span> current velocity is larger than the effective parallel GAM phase velocity Rqω. Qualitative agreement of the theory with co/counter NB injection experiments in COMPASS tokamak is demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1031886','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1031886"><span>Reduced Heat <span class="hlt">Flux</span> Through Preferential Surface Reactions Leading to Vibrationally and <span class="hlt">Electronically</span> Excited Product States</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2016-03-04</p> <p>computational chemistry approaches, capable of modeling nonadiabatic oxygen interactions (<span class="hlt">electronically</span> excited interactions) with surface defects...were developed. Through such computational chemistry modeling we determined precisely how and why such excited-state molecules are produced, by...to interpret the experimental data. The third objective was to develop new computational chemistry approaches capable of modeling the challenging</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990P%26SS...38.1295B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990P%26SS...38.1295B"><span>Auroral precipitation <span class="hlt">flux</span> of ions and <span class="hlt">electrons</span> in Saturn's outer magnetosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barbosa, D. D.</p> <p>1990-10-01</p> <p>This paper examines particles and fields data obtained by Voyager in Saturn's outer magnetosphere with a view toward assessing the role that medium-energy ions and <span class="hlt">electrons</span> have in stimulating the UV aurora. The magnetic field displays a high level of fluctuation of two characteristic types: large-scale coherent depressions in the field strength associated with the plumes of Titan and a small-scale incoherent turbulence presumed to be a consequence of the high-beta plasma environment. <span class="hlt">Electrons</span> are assumed to interact strongly with lower hybrid waves and are accelerated to energies of a few kiloelectron volts. The available energy input to the aurora by protons is 5 x 10 to the 9th W, while an upper bound to that of N(+) ions is about 2 x 10 to the 10th W. <span class="hlt">Electrons</span> in the range 1-10 keV can contribute upward of 5 x 10 to the 10th W and perhaps more if a field-aligned potential drop above the aurora is present. It is concluded that <span class="hlt">electrons</span> are most likely the primary precipitation energy source for the aurora as a result of energy transfer from Titanogenic N(+) pickup ions in a corotation-dominated magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/874724','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/874724"><span>Fast <span class="hlt">flux</span> locked loop</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ganther, Jr., Kenneth R.; Snapp, Lowell D.</p> <p>2002-09-10</p> <p>A <span class="hlt">flux</span> locked loop for providing an electrical feedback signal, the <span class="hlt">flux</span> locked loop employing radio-frequency components and technology to extend the <span class="hlt">flux</span> modulation frequency and tracking loop bandwidth. The <span class="hlt">flux</span> locked loop of the present invention has particularly useful application in read-out <span class="hlt">electronics</span> for DC SQUID magnetic measurement systems, in which case the electrical signal output by the <span class="hlt">flux</span> locked loop represents an unknown magnetic <span class="hlt">flux</span> applied to the DC SQUID.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA538703','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA538703"><span>Pulsar Timing with the Fermi <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2010-12-01</p> <p>Pulsar Timing with the Fermi <span class="hlt">LAT</span> Paul S. Ray∗, Matthew Kerr†, Damien Parent∗∗ and the Fermi PSC‡ ∗Naval Research Laboratory, 4555 Overlook Ave., SW...Laboratory, Washington, DC 20375, USA ‡Fermi Pulsar Search Consortium Abstract. We present an overview of precise pulsar timing using data from the Large...unbinned photon data. In addition to determining the spindown behavior of the pulsars and detecting glitches and timing noise, such timing analyses al</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007880','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007880"><span>FERMI-<span class="hlt">LAT</span> Observations of Galatic Transients</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hays, Elizabeth</p> <p>2010-01-01</p> <p>This slide presentation reviews the use of the Large Area Telescope on the Fermi Observatory observations of Galactic Transients. <span class="hlt">LAT</span> all-sky monitoring is producing spectacular results for the GeV transient sky: (1) New blazars and unidentified transients (2) Probing the jet of the Cygnus X-3 microquasar (3) Discovery of gamma rays from V407 Cygni nova (4) Fast high-energy gamma-ray flares from the Crab Nebula.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JPhCS.390a2060K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JPhCS.390a2060K"><span>Conceptual Design of Vacuum Chamber for testing of high heat <span class="hlt">flux</span> components using <span class="hlt">electron</span> beam as a source</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khan, M. S.; Swamy, Rajamannar; Khirwadkar, S. S.; Divertors Division, Prototype</p> <p>2012-11-01</p> <p>A conceptual design of vacuum chamber is proposed to study the thermal response of high heat <span class="hlt">flux</span> components under energy depositions of the magnitude and durations expected in plasma fusion devices. It is equipped with high power <span class="hlt">electron</span> beam with maximum beam power of 200 KW mounted in a stationary horizontal position from back side of the chamber. The <span class="hlt">electron</span> beam is used as a heat source to evaluate the heat removal capacity, material performance under thermal loads & stresses, thermal fatigue etc on actively cooled mock - ups which are mounted on a flange system which is the front side door of the chamber. The tests mock - ups are connected to a high pressure high temperature water circulation system (HPHT-WCS) operated over a wide range of conditions. The vacuum chamber consists of different ports at different angles to view the mock -up surface available for mock -up diagnostics. The vacuum chamber is pumped with different pumps mounted on side ports of the chamber. The chamber is shielded from X - rays which are generated inside the chamber when high-energy <span class="hlt">electrons</span> are incident on the mock-up. The design includes development of a conceptual design with theoretical calculations and CAD modelling of the system using CATIA V5. These CAD models give an outline on the complete geometry of HHF test chamber, fabrication challenges and safety issues. FEA analysis of the system has been performed to check the structural integrity when the system is subjected to structural & thermal loads.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/632552','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/632552"><span>Onset of diffuse reflectivity and fast <span class="hlt">electron</span> <span class="hlt">flux</span> inhibition in 528-nm-laser{endash}solid interactions at ultrahigh intensity</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Feurer, T.; Theobald, W.; Sauerbrey, R.; Uschmann, I.; Altenbernd, D.; Teubner, U.; Gibbon, P.; Foerster, E.; Malka, G.; Miquel, J.L.</p> <p>1997-10-01</p> <p>Using a high-power femtosecond frequency-doubled Nd:glass laser system with a contrast ratio of 10{sup 12}, the interaction between light and matter up to intensities of 10{sup 19} Wthinspcm{sup {minus}2}has been investigated. The absorption of the laser light in solid aluminum is almost independent of the polarization, peaks at about 25{degree}, and reaches values of almost 45{percent}. Assuming an exponential <span class="hlt">electron</span> distribution, a temperature of 420 keV at 4{times}10{sup 18} Wthinspcm{sup {minus}2}was measured. These experiments and the detection of the hard-x-ray radiation (60 keV{endash}1 MeV) implied a conversion efficiency of 10{sup {minus}4}{endash}10{sup {minus}3} into suprathermal <span class="hlt">electrons</span>. A second low-energy <span class="hlt">electron</span> distribution either with trajectories mainly parallel to the target surface or with a reduced penetration depth due to <span class="hlt">flux</span> inhibition was also inferred from K{alpha} line radiation measurements. {copyright} {ital 1997} {ital The American Physical Society}</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/886010','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/886010"><span>Floating Refrigerant Loop Based on R-134a Refrigerant Cooling of High-Heat <span class="hlt">Flux</span> <span class="hlt">Electronics</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lowe, K.T.</p> <p>2005-10-07</p> <p>The Oak Ridge National Laboratory (ORNL) Power <span class="hlt">Electronics</span> and Electric Machinery Research Center (PEEMRC) have been developing technologies to address the thermal issues associated with hybrid vehicles. Removal of the heat generated from electrical losses in traction motors and their associated power <span class="hlt">electronics</span> is essential for the reliable operation of motors and power <span class="hlt">electronics</span>. As part of a larger thermal control project, which includes shrinking inverter size and direct cooling of <span class="hlt">electronics</span>, ORNL has developed U.S. Patent No. 6,772,603 B2, ''Methods and Apparatus for Thermal Management of Vehicle Systems and Components'' [1], and patent pending, ''Floating Loop System for Cooling Integrated Motors and Inverters Using Hot Liquid Refrigerant'' [2]. The floating-loop system provides a large coefficient of performance (COP) for hybrid-drive component cooling. This loop (based on R-134a) is integrated with a vehicle's existing air-conditioning (AC) condenser, which dissipates waste heat to the ambient air. Because the temperature requirements for cooling of power <span class="hlt">electronics</span> and electric machines are not as low as that required for passenger compartment air, this adjoining loop can operate on the high-pressure side of the existing AC system. This arrangement also allows the floating loop to run without the need for the compressor and only needs a small pump to move the liquid refrigerant. For the design to be viable, the loop must not adversely affect the existing system. The loop should also provide a high COP, a flat-temperature profile, and low-pressure drop. To date, the floating-loop test prototype has successfully removed 2 kW of heat load in a 9 kW automobile passenger AC system with and without the automotive AC system running. The COP for the tested floating-loop system ranges from 40-45, as compared to a typical AC system COP of about 2-4. The estimated required waste-heat load for future hybrid applications is 5.5 kW and the existing system could be</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1355697','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1355697"><span><i>Fermi</i> <span class="hlt">LAT</span> Stacking Analysis of <i>Swift</i> Localized GRBs</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ackermann, M.; Ajello, M.; Anderson, B.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bhat, P. N.; Bissaldi, E.; Bonino, R.; Bottacini, E.; Brandt, T. J.; Bregeon, J.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caragiulo, M.; Caraveo, P. A.; Cecchi, C.; Charles, E.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; D’Ammando, F.; de Angelis, A.; de Palma, F.; Desiante, R.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Focke, W. B.; Franckowiak, A.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Giglietto, N.; Giordano, F.; Giroletti, M.; Godfrey, G.; Grenier, I. A.; Grove, J. E.; Guiriec, S.; Hewitt, J. W.; Hill, A. B.; Horan, D.; Jóhannesson, G.; Kocevski, D.; Kouveliotou, C.; Kuss, M.; Larsson, S.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Mayer, M.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Murgia, S.; Nemmen, R.; Nuss, E.; Ohno, M.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Racusin, J. L.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Schaal, M.; Schulz, A.; Sgrò, C.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Takahashi, H.; Thayer, J. B.; Tibaldo, L.; Tinivella, M.; Torres, D. F.; Tosti, G.; Troja, E.; Vianello, G.; Kienlin, A. von; Werner, M.; Wood, K. S.</p> <p>2016-05-05</p> <p>In this paper, we perform a comprehensive stacking analysis of data collected by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) of γ-ray bursts (GRBs) localized by the Swift spacecraft, which were not detected by the <span class="hlt">LAT</span> but which fell within the instrument's field of view at the time of trigger. We examine a total of 79 GRBs by comparing the observed counts over a range of time intervals to that expected from designated background orbits, as well as by using a joint likelihood technique to model the expected distribution of stacked counts. We find strong evidence for subthreshold emission at MeV to GeV energies using both techniques. This observed excess is detected during intervals that include and exceed the durations typically characterizing the prompt emission observed at keV energies and lasts at least 2700 s after the co-aligned burst trigger. By utilizing a novel cumulative likelihood analysis, we find that although a burst's prompt γ-ray and afterglow X-ray <span class="hlt">flux</span> both correlate with the strength of the subthreshold emission, the X-ray afterglow <span class="hlt">flux</span> measured by Swift's X-ray Telescope at 11 hr post trigger correlates far more significantly. Overall, the extended nature of the subthreshold emission and its connection to the burst's afterglow brightness lend further support to the external forward shock origin of the late-time emission detected by the <span class="hlt">LAT</span>. Finally, these results suggest that the extended high-energy emission observed by the <span class="hlt">LAT</span> may be a relatively common feature but remains undetected in a majority of bursts owing to instrumental threshold effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26846653','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26846653"><span>Obstacles in the quantification of the cyclic <span class="hlt">electron</span> <span class="hlt">flux</span> around Photosystem I in leaves of C3 plants.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fan, Da-Yong; Fitzpatrick, Duncan; Oguchi, Riichi; Ma, Weimin; Kou, Jiancun; Chow, Wah Soon</p> <p>2016-09-01</p> <p>Sixty years ago Arnon and co-workers discovered photophosphorylation driven by a cyclic <span class="hlt">electron</span> <span class="hlt">flux</span> (CEF) around Photosystem I. Since then understanding the physiological roles and the regulation of CEF has progressed, mainly via genetic approaches. One basic problem remains, however: quantifying CEF in the absence of a net product. Quantification of CEF under physiological conditions is a crucial prerequisite for investigating the physiological roles of CEF. Here we summarize current progress in methods of CEF quantification in leaves and, in some cases, in isolated thylakoids, of C3 plants. Evidently, all present methods have their own shortcomings. We conclude that to quantify CEF in vivo, the best way currently is to measure the <span class="hlt">electron</span> <span class="hlt">flux</span> through PS I (ETR1) and that through PS II and PS I in series (ETR2) for the whole leaf tissue under identical conditions. The difference between ETR1 and ETR2 is an upper estimate of CEF, mainly consisting, in C3 plants, of a major PGR5-PGRL1-dependent CEF component and a minor chloroplast NDH-dependent component, where PGR5 stands for Proton Gradient Regulation 5 protein, PGRL1 for PGR5-like photosynthesis phenotype 1, and NDH for Chloroplast NADH dehydrogenase-like complex. These two CEF components can be separated by the use of antimycin A to inhibit the former (major) component. Membrane inlet mass spectrometry utilizing stable oxygen isotopes provides a reliable estimation of ETR2, whilst ETR1 can be estimated from a method based on the photochemical yield of PS I, Y(I). However, some issues for the recommended method remain unresolved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4561719','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4561719"><span>Rerouting Cellular <span class="hlt">Electron</span> <span class="hlt">Flux</span> To Increase the Rate of Biological Methane Production</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Catlett, Jennie L.; Ortiz, Alicia M.</p> <p>2015-01-01</p> <p>Methanogens are anaerobic archaea that grow by producing methane, a gas that is both an efficient renewable fuel and a potent greenhouse gas. We observed that overexpression of the cytoplasmic heterodisulfide reductase enzyme HdrABC increased the rate of methane production from methanol by 30% without affecting the growth rate relative to the parent strain. Hdr enzymes are essential in all known methane-producing archaea. They function as the terminal oxidases in the methanogen <span class="hlt">electron</span> transport system by reducing the coenzyme M (2-mercaptoethane sulfonate) and coenzyme B (7-mercaptoheptanoylthreonine sulfonate) heterodisulfide, CoM-S-S-CoB, to regenerate the thiol-coenzymes for reuse. In Methanosarcina acetivorans, HdrABC expression caused an increased rate of methanogenesis and a decrease in metabolic efficiency on methylotrophic substrates. When acetate was the sole carbon and energy source, neither deletion nor overexpression of HdrABC had an effect on growth or methane production rates. These results suggest that in cells grown on methylated substrates, the cell compensates for energy losses due to expression of HdrABC with an increased rate of substrate turnover and that HdrABC lacks the appropriate <span class="hlt">electron</span> donor in acetate-grown cells. PMID:26162885</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26162885','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26162885"><span>Rerouting Cellular <span class="hlt">Electron</span> <span class="hlt">Flux</span> To Increase the Rate of Biological Methane Production.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Catlett, Jennie L; Ortiz, Alicia M; Buan, Nicole R</p> <p>2015-10-01</p> <p>Methanogens are anaerobic archaea that grow by producing methane, a gas that is both an efficient renewable fuel and a potent greenhouse gas. We observed that overexpression of the cytoplasmic heterodisulfide reductase enzyme HdrABC increased the rate of methane production from methanol by 30% without affecting the growth rate relative to the parent strain. Hdr enzymes are essential in all known methane-producing archaea. They function as the terminal oxidases in the methanogen <span class="hlt">electron</span> transport system by reducing the coenzyme M (2-mercaptoethane sulfonate) and coenzyme B (7-mercaptoheptanoylthreonine sulfonate) heterodisulfide, CoM-S-S-CoB, to regenerate the thiol-coenzymes for reuse. In Methanosarcina acetivorans, HdrABC expression caused an increased rate of methanogenesis and a decrease in metabolic efficiency on methylotrophic substrates. When acetate was the sole carbon and energy source, neither deletion nor overexpression of HdrABC had an effect on growth or methane production rates. These results suggest that in cells grown on methylated substrates, the cell compensates for energy losses due to expression of HdrABC with an increased rate of substrate turnover and that HdrABC lacks the appropriate <span class="hlt">electron</span> donor in acetate-grown cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011A%26A...535A..19L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011A%26A...535A..19L"><span>Search for high-energy γ-ray emission from galaxies of the Local Group with Fermi/<span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lenain, J.-P.; Walter, R.</p> <p>2011-11-01</p> <p>Context. With the discovery of high-energy γ-ray emission from the Andromeda galaxy (M 31) by the Fermi/<span class="hlt">LAT</span> collaboration, normal galaxies begin to arise from the shadows for the first time, providing insight into cosmic ray acceleration in external galaxies. Aims: We search for high-energy γ-ray emission from those galaxies in the Local Group that have so far not been investigated: M 81, M 83, IC 342, Maffei 1, Maffei 2, and M 94. Methods.Fermi/<span class="hlt">LAT</span> public data from August 4, 2008 to January 1, 2011 were analysed for these galaxies. We compared the results to other starburst and normal galaxies detected so far at high energies: the Magellanic clouds, M 31, and the starburst galaxies M 82 and NGC 253. Results: No significant detection is found in the data for the sources in our sample, and we derive upper limits on their photon <span class="hlt">flux</span>. After comparing the results to other Local Group objects, we find that the derived upper limits are fully compatible with expectations from cosmic rays interacting with the interstellar medium within the host galaxies. In the case of M 33 and M 83, a detection in Fermi/<span class="hlt">LAT</span> data should be imminent. The expected <span class="hlt">fluxes</span> for the other sources in the sample are below the sensitivity of Fermi/<span class="hlt">LAT</span>, even after 10 years of observation. Collective emission from compact objects in the host galaxies is also found to be negligible compared to the expected emission from cosmic ray interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJS..232...18A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJS..232...18A"><span>3FHL: The Third Catalog of Hard Fermi-<span class="hlt">LAT</span> Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ajello, M.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bregeon, J.; Britto, R. J.; Bruel, P.; Buehler, R.; Buson, S.; Cameron, R. A.; Caputo, R.; Caragiulo, M.; Caraveo, P. A.; Cavazzuti, E.; Cecchi, C.; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiaro, G.; Ciprini, S.; Cohen, J. M.; Costantin, D.; Costanza, F.; Cuoco, A.; Cutini, S.; D’Ammando, F.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Domínguez, A.; Drell, P. S.; Dumora, D.; Favuzzi, C.; Fegan, S. J.; Ferrara, E. C.; Fortin, P.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Green, D.; Grenier, I. A.; Grondin, M.-H.; Grove, J. E.; Guillemot, L.; Guiriec, S.; Harding, A. K.; Hays, E.; Hewitt, J. W.; Horan, D.; Jóhannesson, G.; Kensei, S.; Kuss, M.; La Mura, G.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Li, J.; Longo, F.; Loparco, F.; Lott, B.; Lubrano, P.; Magill, J. D.; Maldera, S.; Manfreda, A.; Mazziotta, M. N.; McEnery, J. E.; Meyer, M.; Michelson, P. F.; Mirabal, N.; Mitthumsiri, W.; Mizuno, T.; Moiseev, A. A.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Negro, M.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Palatiello, M.; Paliya, V. S.; Paneque, D.; Perkins, J. S.; Persic, M.; Pesce-Rollins, M.; Piron, F.; Porter, T. A.; Principe, G.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Reposeur, T.; Saz Parkinson, P. M.; Sgrò, C.; Simone, D.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Stawarz, L.; Suson, D. J.; Takahashi, M.; Tak, D.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Torres, D. F.; Torresi, E.; Troja, E.; Vianello, G.; Wood, K.; Wood, M.</p> <p>2017-10-01</p> <p>We present a catalog of sources detected above 10 GeV by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) in the first 7 years of data using the Pass 8 event-level analysis. This is the Third Catalog of Hard Fermi-<span class="hlt">LAT</span> Sources (3FHL), containing 1556 objects characterized in the 10 GeV–2 TeV energy range. The sensitivity and angular resolution are improved by factors of 3 and 2 relative to the previous <span class="hlt">LAT</span> catalog at the same energies (1FHL). The vast majority of detected sources (79%) are associated with extragalactic counterparts at other wavelengths, including 16 sources located at very high redshift (z > 2). Of the sources, 8% have Galactic counterparts and 13% are unassociated (or associated with a source of unknown nature). The high-latitude sky and the Galactic plane are observed with a <span class="hlt">flux</span> sensitivity of 4.4 to 9.5 × 10‑11 ph cm‑2 s‑1, respectively (this is approximately 0.5% and 1% of the Crab Nebula <span class="hlt">flux</span> above 10 GeV). The catalog includes 214 new γ-ray sources. The substantial increase in the number of photons (more than 4 times relative to 1FHL and 10 times to 2FHL) also allows us to measure significant spectral curvature for 32 sources and find <span class="hlt">flux</span> variability for 163 of them. Furthermore, we estimate that for the same <span class="hlt">flux</span> limit of 10‑12 erg cm‑2 s‑1, the energy range above 10 GeV has twice as many sources as the range above 50 GeV, highlighting the importance, for future Cherenkov telescopes, of lowering the energy threshold as much as possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22314277','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22314277"><span>Compact and high-particle-<span class="hlt">flux</span> thermal-lithium-beam probe system for measurement of two-dimensional <span class="hlt">electron</span> density profile</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shibata, Y. Manabe, T.; Ohno, N.; Takagi, M.; Kajita, S.; Tsuchiya, H.; Morisaki, T.</p> <p>2014-09-15</p> <p>A compact and high-particle-<span class="hlt">flux</span> thermal-lithium-beam source for two-dimensional measurement of <span class="hlt">electron</span> density profiles has been developed. The thermal-lithium-beam oven is heated by a carbon heater. In this system, the maximum particle <span class="hlt">flux</span> of the thermal lithium beam was ∼4 × 10{sup 19} m{sup −2} s{sup −1} when the temperature of the thermal-lithium-beam oven was 900 K. The <span class="hlt">electron</span> density profile was evaluated in the small tokamak device HYBTOK-II. The <span class="hlt">electron</span> density profile was reconstructed using the thermal-lithium-beam probe data and this profile was consistent with the <span class="hlt">electron</span> density profile measured with a Langmuir electrostatic probe. We confirm that the developed thermal-lithium-beam probe can be used to measure the two-dimensional <span class="hlt">electron</span> density profile with high time and spatial resolutions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090007929&hterms=galileo&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dgalileo','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090007929&hterms=galileo&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dgalileo"><span>Analysis of the Variation of Energetic <span class="hlt">Electron</span> <span class="hlt">Flux</span> with Respect to Longitude and Distance Normal to the Magnetic Equatorial Plane for Galileo Energetic Particle Detector Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Swimm, Randall; Garrett, Henry B.; Jun, Insoo; Evans, Robin W.</p> <p>2004-01-01</p> <p>In this study we examine ten-minute omni-directional averages of energetic <span class="hlt">electron</span> data measured by the Galileo spacecraft Energetic Particle Detector (EPD). Count rates from <span class="hlt">electron</span> channels B1, DC2, and DC3 are evaluated using a power law model to yield estimates of the differential <span class="hlt">electron</span> <span class="hlt">fluxes</span> from 1 MeV to 11 MeV at distances between 8 and 51 Jupiter radii. Whereas the orbit of the Galileo spacecraft remained close to the rotational equatorial plane of Jupiter, the approximately 11 degree tilt of the magnetic axis of Jupiter relative to its rotational axis allowed the EPD instrument to sample high energy <span class="hlt">electrons</span> at limited distances normal to the magnetic equatorial plane. We present a Fourier analysis of the semi-diurnal variation of <span class="hlt">electron</span> <span class="hlt">fluxes</span> with longitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090007929&hterms=particle+detector&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dparticle%2Bdetector','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090007929&hterms=particle+detector&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dparticle%2Bdetector"><span>Analysis of the Variation of Energetic <span class="hlt">Electron</span> <span class="hlt">Flux</span> with Respect to Longitude and Distance Normal to the Magnetic Equatorial Plane for Galileo Energetic Particle Detector Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Swimm, Randall; Garrett, Henry B.; Jun, Insoo; Evans, Robin W.</p> <p>2004-01-01</p> <p>In this study we examine ten-minute omni-directional averages of energetic <span class="hlt">electron</span> data measured by the Galileo spacecraft Energetic Particle Detector (EPD). Count rates from <span class="hlt">electron</span> channels B1, DC2, and DC3 are evaluated using a power law model to yield estimates of the differential <span class="hlt">electron</span> <span class="hlt">fluxes</span> from 1 MeV to 11 MeV at distances between 8 and 51 Jupiter radii. Whereas the orbit of the Galileo spacecraft remained close to the rotational equatorial plane of Jupiter, the approximately 11 degree tilt of the magnetic axis of Jupiter relative to its rotational axis allowed the EPD instrument to sample high energy <span class="hlt">electrons</span> at limited distances normal to the magnetic equatorial plane. We present a Fourier analysis of the semi-diurnal variation of <span class="hlt">electron</span> <span class="hlt">fluxes</span> with longitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1014430','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1014430"><span><span class="hlt">Lat</span>Mix 2011 and 2012 Dispersion Analysis</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2015-09-30</p> <p>1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. <span class="hlt">Lat</span>Mix 2011 and 2012 Dispersion Analysis Miles A...continue analysis and publication of results obtained during the “Scalable Lateral Mixing and Coherent Turbulence” (a.k.a., <span class="hlt">Lat</span>Mix) DRI. The initial...work included the airborne lidar operations as well as a substantial part of the field operations and analysis . A primary objective of our <span class="hlt">Lat</span>Mix</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM21A2445S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM21A2445S"><span>Differential <span class="hlt">Electron</span> <span class="hlt">Flux</span> Spectra Measured by the Magnetospheric Multiscale Mission (MMS) Show Strong Field-aligned <span class="hlt">Electron</span> Population of Ionospheric Origin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schiff, C.; Khazanov, G. V.; Giles, B. L.; Avanov, L. A.; Burch, J. L.; Coffey, V. N.; Dorelli, J.; Gershman, D. J.; Lavraud, B.; Moore, T. E.; Paterson, W. R.; Pollock, C. J.; Russell, C. T.; Strangeway, R. J.</p> <p>2016-12-01</p> <p>Ionospheric outflow is the process in which neutral atoms in the Earth's atmosphere are first ionized and then accelerated so that the component ions and <span class="hlt">electrons</span> can transport from regions of low altitude (h 0.5 RE) into the magnetosphere, reaching distances ranging up to 15 RE and beyond. It is an important process in atmospheric loss that is only partially understood and refinements of the theory by experimental observation is crucial to developing a better understanding its role in the long-term fate of the Earth's atmosphere. In addition, it is a source of various plasma populations (in particular O+) whose influence on the interaction between the magnetosphere and the solar wind must be accounted for in order to get an accurate picture of the relevant plasma dynamics. In this study, fast survey measurements (4.5 s) from the Fast Plasma Investigation (FPI) <span class="hlt">electron</span> spectrometers onboard the MMS spacecraft are used to construct differential <span class="hlt">electron</span> <span class="hlt">flux</span>, Φe, spectra over the energy range from 10 eV to 30 KeV. The time period of the study is from 04:00 to 06:00 UTC on Oct. 26, 2015, when the MMS formation was approximately at 10 RE and at a local time of about 14:00. Using the 32x16 angular resolution (angular bins of 11.25 degrees) of an FPI skymap, these spectra are further refined by binning pitch angles, α, every 20 degrees. The resulting spectra show a very large population of cold <span class="hlt">electrons</span> (Φe ≈ 106 s-1 cm-2 eV-1) at low energies (10-60 eV) that are strongly aligned with the magnetic field (counterstreaming with a density 3 times larger than the perpendicular population). The distribution, which falls off rapidly with increasing energy, exhibits a knee at about 100 eV, indicative of where the magnetospheric population becomes dominant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26992792','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26992792"><span>Modifying the endogenous <span class="hlt">electron</span> <span class="hlt">fluxes</span> of Rhodobacter sphaeroides 2.4.1 for improved electricity generation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wong, Man Tung; Cheng, Danhui; Wang, Ri; Hsing, I-Ming</p> <p>2016-05-01</p> <p>The purple bacteria Rhodobacter sphaeroides serve as a promising biocatalyst in the photo-microbial fuel cell system (photo-MFC). This gram-negative species performs highly efficient anoxygenic photosynthesis that ensures an anaerobic environment in the anode compartment. Previous studies incorporating R. sphaeroides into photo-MFC were conducted using platinum as the anode electrode. In this study, we detected a steady current generation of R. sphaeroides in a bioelectrochemical system where glassy carbon was the working electrode and a typical growth medium was the electrolyte. The bioelectricity generation synchronized with the supplementation of reduced carbon source and showed immediate response to illumination, which strongly indicated the correlation between the observed current and the cytoplasmic quinone activity. Modifications of the endogenous <span class="hlt">electron</span> flows mediated by quinone pool are shown to have significantly enhanced the bioelectricity generation. We anticipate that the findings in this study would advance future optimization of R. sphaeroides as an anode strain, as well as facilitate the study of bioenergetics in photosynthetic bacteria.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM31A2438D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM31A2438D"><span>On the ultra-low frequency wave contributions to the relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> dynamics in the outer Van Allen radiation belt</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dal Lago, A.; Marchezi, J. P.; Alves, L. R.; da Silva, L.; Dallaqua, R.; Medeiros, C.; Souza, V. M. C. E. S.; Rockenbach, M.; Vieira, L.; Mendes, O., Jr.; Sibeck, D. G.; Kanekal, S. G.; Kletzing, C.; Baker, D. N.; Wygant, J. R.</p> <p>2016-12-01</p> <p>Various physical processes can contribute to loss and acceleration of energetic <span class="hlt">electrons</span> in the Earth's radiation belts. In the range of 1 mHz to 10 Hz, ultra-low frequency (ULF) waves are known to cause significant changes in the energetic particle <span class="hlt">flux</span> in the radiation belts. On board the Van Allen Probes, the Relativistic <span class="hlt">Electron</span> Proton Telescope (REPT) measures the relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> in the outer radiation belts in the energy range from 1.8 MeV up to 20 MeV. We selected events that have significant <span class="hlt">electron</span> <span class="hlt">flux</span> dropouts, classified into two categories regarding the time elapsed between the outer radiation belt dropout and the refurbishing, namely events that time scale had taken (i) a few hours and, (ii) some days. This work aims to investigate the presence of ULF waves using the radial and azimuthal magnetic and electric field components recorded by the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS). The evaluation of the power spectral density of those components unravels the poloidal and toroidal characteristc of the rapid compressional waves. We discuss how these modes can contribute to modifications of the relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> considering the (i) and (ii) cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1357514','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1357514"><span>Detection of the Small Magellanic Cloud in gamma-rays with  <i>Fermi</i> /<span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.</p> <p>2010-11-01</p> <p>Context. The <span class="hlt">flux</span> of gamma rays with energies greater than 100 MeV is dominated by diffuse emission coming from cosmic-rays (CRs) illuminating the interstellar medium (ISM) of our Galaxy through the processes of Bremsstrahlung, pion production and decay, and inverse-Compton scattering. The study of this diffuse emission provides insight into the origin and transport of cosmic rays. Aims. We searched for gamma-ray emission from the Small Magellanic Cloud (SMC) in order to derive constraints on the cosmic-ray population and transport in an external system with properties different from the Milky Way. Methods. We analysed the first 17 months of continuous all-sky observations by the Large Area Telescope (<span class="hlt">LAT</span>) of the Fermi mission to determine the spatial distribution, <span class="hlt">flux</span> and spectrum of the gamma-ray emission from the SMC. We also used past radio synchrotron observations of the SMC to study the population of CR <span class="hlt">electrons</span> specifically. Results. We obtained the first detection of the SMC in high-energy gamma rays, with an integrated >100 MeV <span class="hlt">flux</span> of (3.7 ± 0.7) × 10<sup>-8</sup> ph cm<sup>-2</sup> s<sup>-1</sup>, with additional systematic uncertainty of ≤16%. The emission is steady and from an extended source ~3° in size. It is not clearly correlated with the distribution of massive stars or neutral gas, nor with known pulsars or supernova remnants, but a certain correlation with supergiant shells is observed. Conclusions. The observed <span class="hlt">flux</span> implies an upper limit on the average CR nuclei density in the SMC of ~15% of the value measured locally in the Milky Way. The population of high-energy pulsars of the SMC may account for a substantial fraction of the gamma-ray <span class="hlt">flux</span>, which would make the inferred CR nuclei density even lower. The average density of CR <span class="hlt">electrons</span> derived from radio synchrotron observations is consistent with the same reduction factor but the uncertainties are large. From our current knowledge of the SMC, such a low CR density does not seem to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JPhCS.136d2093T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JPhCS.136d2093T"><span>Study of the <span class="hlt">electronic</span> structure of Ce-based heavy-fermion systems exposed to the low-energy neutrino dense <span class="hlt">flux</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trapeznikov, V. A.; Shabanova, I. N.; Murin, A. V.</p> <p>2008-11-01</p> <p>The class of compounds based on f-elements (Ce) attracts great attention because of their unusual properties. They are characterized by a heavy-fermion state, which occurs in them under certain external actions. Heavy-fermion materials have unique properties. The objective of the work is the investigation of a change in the <span class="hlt">electronic</span> structure in a number of Ce-based systems under the action of a dense neutrino <span class="hlt">flux</span> in order to develop the technology for the essential change of material properties. To increase the density of the neutrino <span class="hlt">flux</span> by several orders of magnitude, the phenomenon of diffraction is used. The investigation of the <span class="hlt">electronic</span> structure of Ce-based systems on the <span class="hlt">electron</span> magnetic spectrometer using the x-ray <span class="hlt">electron</span> method and the calculations of the density of states at different temperatures has shown the decrease in the intensity of the localized resonance maximum near Fermi level with increasing temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25036824','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25036824"><span>O2-dependent large <span class="hlt">electron</span> flow functioned as an <span class="hlt">electron</span> sink, replacing the steady-state <span class="hlt">electron</span> <span class="hlt">flux</span> in photosynthesis in the cyanobacterium Synechocystis sp. PCC 6803, but not in the cyanobacterium Synechococcus sp. PCC 7942.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hayashi, Ryosuke; Shimakawa, Ginga; Shaku, Keiichiro; Shimizu, Satoko; Akimoto, Seiji; Yamamoto, Hiroshi; Amako, Katsumi; Sugimoto, Toshio; Tamoi, Masahiro; Makino, Amane; Miyake, Chikahiro</p> <p>2014-01-01</p> <p>To determine whether alternative <span class="hlt">electron</span> flow (AEF) can replace the photosynthetic <span class="hlt">electron</span> flow in cyanobacteria, we used an open O2-electrode system to monitor O2-exchange over a long period. In air-grown Synechocystis sp. PCC 6803 (S. 6803(WT)), the quantum yield of PSII, Y(II), held even after photosynthesis was suppressed by CO2 shortage. The S. 6803 mutant, deficient in flavodiiron (FLV) proteins 1 and 3, showed the same phenotype as S. 6803(WT). In contrast, Y(II) decreased in Synechococcus sp. PCC 7942 (S. 7942). These results suggest that AEF functioned as the Y(II) in S. 6803 and replaced the photosynthetic <span class="hlt">electron</span> <span class="hlt">flux</span>. In contrast, the activity of AEF in S. 7942 was lower. The affinity of AEF for O2 in S. 6803 did not correspond to those of FLVs in bacteria or terminal oxidases in respiration. AEF might be driven by photorespiration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.8219....1P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.8219....1P"><span>Fermi <span class="hlt">LAT</span> detection of increasing gamma-ray activity from NGC 1275 and B3 0908+416B</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pivato, G.; Buson, S.</p> <p>2015-10-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from sources positionally consistent with the flat spectrum radio quasar B3 0908+416B (also known as 3FGL J0912.2+4126, Acero et al. 2015 ApJS, 218, 23) and the radio galaxy NGC 1275 (also known as Perseus A and 3FGL J0319.8+4130).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ATel.9442....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ATel.9442....1C"><span>Fermi <span class="hlt">LAT</span> detection of a GeV gamma-ray flare from the BL Lac object AP Librae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ciprini, Stefano</p> <p>2016-08-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the BL Lac object AP Lib (also known as PKS 1514-24 and 3FGL J1517.6-2422), with radio counterpart position R.A.: 229.424221 deg, Dec.: -24.372076 deg, (J2000.0, Johnston et al. 1995, AJ, 110, 880).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.7330....1O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.7330....1O"><span>Fermi <span class="hlt">LAT</span> Detection of a Gamma-ray Flare from the FSRQ PMN J1703-6212</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ojha, Roopesh; Carpen, Bryce</p> <p>2015-03-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar (FSRQ) PMN J1703-6212 (RA: 255.9022550 deg, Dec: -62.2111133 deg, J2000, Fey et al., 2004, AJ, 127, 1791) at z = 1.755 (Titov et al., 2011, AJ, 142, 165).</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ATel.4225....1D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ATel.4225....1D"><span>Fermi <span class="hlt">LAT</span> detection of renewed gamma-ray activity from the FSRQ PKS 2326-502</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>D'Ammando, F.; Torresi, E.</p> <p>2012-06-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope has observed an increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the Flat Spectrum Radio Quasar PKS 2326-502 (also known as 2FGL J2329.2-4956, Nolan et al. 2012, ApJS, 199, 31; R.A.=23:29:20.880 Dec.=-49:55:40.68, J2000.0, Costa and Loyola 1996, A&AS, 115, 75) at redshift z=0.518 (Jauncey et al. 1984, ApJ, 286, 498).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.8478....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.8478....1C"><span>Fermi <span class="hlt">LAT</span> Detection of a Rapid, Powerful Gamma-ray Flare of the FSRQ CTA 102</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carpenter, Bryce; Ojha, Roopesh</p> <p>2015-12-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar CTA 102 (also known as 3FGL J2232.5+1143, Acero et al. 2015, ApJS, 218, 23) with radio coordinates R.A.: 338.1517038 deg, Dec: 11.7308067 deg (J2000, Johnston et al. 1995, AJ, 110, 880) at redshift z=1.037 (Schmidt 1965, ApJ, 141, 1295).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.7592....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.7592....1C"><span>Fermi <span class="hlt">LAT</span> detection of renewed activity from the blazar PKS 1502+106</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ciprini, Stefano</p> <p>2015-06-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar PKS 1502+106 (also known as OR 103, S3 1502+10 and 3FGL J1504.4+1029, Acero et al., arXiv:1501.02003), with radio coordinates, (J2000.0), R.A.: 226.10408 deg, Dec: 10.49422 deg (Johnston et al. 1995, AJ, 110, 880). This blazar has a redshift of z=1.8383 (Hewett & Wild 2010, MNRAS, 405, 2302).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ATel.7596....1B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ATel.7596....1B"><span>Fermi <span class="hlt">LAT</span> Detection of a Gamma-ray Flare from the BL Lac Object ON 246</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Becerra, Josefa</p> <p>2015-06-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the BL Lac object ON 246 (RA=187.55871 deg, Dec=25.30198 deg, J2000, Beasley et al. 2002, ApJS, 141, 13; with redshift z=0.135, Nass et al. 1996, A&A, 309, 419), also known as S3 1227+25 and 3FGL J1230.3+2519 (3FGL; Acero et al. 2015, arXiv:1501.02003).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ATel.4609....1T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ATel.4609....1T"><span>Fermi <span class="hlt">LAT</span> detection of increased gamma-ray activity from the blazar TXS 1318+225</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Torresi, E.; D'Ammando, F.; Tanaka, Y.</p> <p>2012-11-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) onboard the Fermi Gamma-ray Space Telescope, has observed an increase in the gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar TXS 1318+225 (z=0.943, Sowards-Emmerd et al. 2003, ApJ, 590, 109; RA=200.2966771 deg, Dec=22.2700300 deg, J2000), also known as 2FGL J1321.1+2215 (Nolan et al. 2012, ApJS, 199, 31).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ATel.4858....1O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ATel.4858....1O"><span>Fermi <span class="hlt">LAT</span> detection of a new gamma-ray flare from FSRQ PKS 0502+049</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ojha, Roopesh; Dutka, Michael</p> <p>2013-03-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar PKS 0502+049 (also known as 2FGL J0505.5+0501, Nolan et al. 2012 ApJS, 199, 31). PKS 0502+049 has coordinates RA=05h05m23.1847s DEC=+04d59m42.725s, J2000, (Johnston et al. 1995, AJ, 110, 880) and redshift z=0.954 (Drinkwater et al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ATel.4941....1O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ATel.4941....1O"><span>Fermi <span class="hlt">LAT</span> detection of a gamma-ray flare from FSRQ S5 1044+71</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ojha, Roopesh; Carpenter, Bryce; Dutka, Michael</p> <p>2013-04-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar S5 1044+71 (also known as 2FGL J1048.3+7144, Nolan et al. 2012, ApJS, 199, 31). Localization analysis has ruled out the nearby source 2FGL J1049.7+7240 as a possible counterpart. S5 1044+71 has coordinates RA=10h48m27.6199s DEC=+71d43m35.938s, J2000, (Johnston et al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ATel.4574....1D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ATel.4574....1D"><span>Fermi <span class="hlt">LAT</span> detection of a GeV flare from the blazar PKS 0250-225</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dutka, Michael; Ojha, Roopesh</p> <p>2012-11-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar PKS 0250-225 (also known as 2FGL J0252.7-2218, Nolan et al. 2012 ApJS, 199, 31). PKS 0250-225 has the coordinates RA=02h52m47.9536s, DEC=-22d19m25.465s, J2000, (Beasley et al. 2002 ApJS, 141, 13) and redshift z=1.419 (Shaw et al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ATel.5022....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ATel.5022....1C"><span>Fermi <span class="hlt">LAT</span> Detection of a GeV Flare from FSRQ PKS 2320-035</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carpenter, Bryce; Ojha, Roopesh</p> <p>2013-04-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the flat spectrum radio quasar PKS 2320-035 (also known as 2FGL J2323.6-0316, Nolan et al. 2012, ApJS, 199, 31). PKS 2320-035 has coordinates RA=23h23m31.9537s DEC=-03d17m05.023s, J2000, (Johnston et al. 1995, AJ, 110, 880) and redshift z=1.41 (Browne et al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ATel.5680....1B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ATel.5680....1B"><span>Fermi <span class="hlt">LAT</span> detection of a GeV flare from the FSRQ 3C 279</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buson, S.</p> <p>2013-12-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed an increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with the blazar 3C279 (RA: 194.0465271, Dec: -5.7893119 , Johnston et al.1995, AJ, 110, 880, J2000). This source is classified as a flat spectrum radio quasar (FSRQ) at redshift of 0.536 (Marziani et al. ApJS, 1996, 104, 37) and is one of the three FSRQs known to be VHE gamma-ray emitters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/826603','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/826603"><span>Analysis of Burst Observations by GLAST'S <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Band, D</p> <p>2003-12-17</p> <p>Analyzing data from GLAST's Large Area Telescope (<span class="hlt">LAT</span>) will require sophisticated techniques. The PSF and effective area are functions of both photon energy and the position in the field-of-view. During most of the mission the observatory will survey the sky continuously and thus the <span class="hlt">LAT</span> will detect each count from a source at a different detector orientation; each count requires its own response function. The likelihood as a function of celestial position and photon energy will be the foundation of the standard analysis techniques. However the 20 MeV-300 GeV emission at the time of the {approx}100 keV burst emission (timescale of {approx}10 s) can be isolated and analyzed because essentially no non-burst counts are expected within a PSF radius of the burst location during the burst. Both binned and unbinned (in energy) spectral fitting will be possible. Longer timescale afterglow emission will require the likelihood analysis that will be used for persistent sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/918534','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/918534"><span><span class="hlt">LAT</span> Observation of GRBs: Simulations and Sensitivity Studies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Omodei, Nicola; Norris, Jay; /Denver U.</p> <p>2007-10-22</p> <p>The GLAST Large Area Telescope (<span class="hlt">LAT</span>) is the next generation satellite experiment for high-energy gamma-ray astronomy. It employs a pair conversion technique to record photons in the energy range from 20 MeV to more than 300 GeV. The <span class="hlt">LAT</span> will follow the steps from its predecessor EGRET (1991-2000), and will explore the high-energy gamma-ray sky with unprecedented capabilities. The observation of Gamma-Ray Bursts is one of the main science goal of the <span class="hlt">LAT</span>: in this contribution we compute an estimation of the <span class="hlt">LAT</span> sensitivity to GRB, adopting a phenomenological description of GRBs, where the high-energy emission in GRB is obtained extrapolating the observed BATSE spectrum up to <span class="hlt">LAT</span> energies. The effect of the cosmological attenuation is included. We use the BATSE current catalog to build up our statistics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080043890&hterms=instant&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dinstant','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080043890&hterms=instant&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dinstant"><span>The Capabilities of the GLAST <span class="hlt">LAT</span> for Blazar Variability Studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McEnery, Julie</p> <p>2008-01-01</p> <p>One of the more notable features of the Large Area Telescope (<span class="hlt">LAT</span>) on GLAST is its extremely large field of view, which covers more than 20% of the sky at any instant. In survey mode the <span class="hlt">LAT</span> will be rocked about the orbital plane to provide coverage of the entire gamma-ray sky above 20 MeV every three hours. This will be the default observing mode for the first year of operations and is likely to be the dominant observing mode throughout the rest of the mission. Thus the <span class="hlt">LAT</span> will provide long, evenly sampled, gamma-ray lightcurves for a large number of sources. In this talk we describe the nature and quality of the data that will be provided by the <span class="hlt">LAT</span> and use simulated lightcurves to illustrate some of the scientific questions that can be addressed with <span class="hlt">LAT</span> observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21067770','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21067770"><span><span class="hlt">LAT</span> observation of GRBs: Simulations and Sensitivity studies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Omodei, Nicola; Norris, Jay</p> <p>2007-07-12</p> <p>The GLAST Large Area Telescope (<span class="hlt">LAT</span>) is the next generation satellite experiment for high-energy gamma-ray astronomy. It employs a pair conversion technique to record photons in the energy range from 20 MeV to more than 300 GeV. The <span class="hlt">LAT</span> will follow the steps from its predecessor EGRET (1991-2000), and will explore the high-energy gamma-ray sky with unprecedented capabilities. The observation of Gamma-Ray Bursts is one of the main science goal of the <span class="hlt">LAT</span>: in this contribution we compute an estimation of the <span class="hlt">LAT</span> sensitivity to GRB, adopting a phenomenological description of GRBs, where the high-energy emission in GRB is obtained extrapolating the observed BATSE spectrum up to <span class="hlt">LAT</span> energies. The effect of the cosmological attenuation is included. We use the BATSE current catalog to build up our statistics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1049755','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1049755"><span>Fermi-<span class="hlt">LAT</span> Observation of Supernova Remnant S147</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Katsuta, J.; Uchiyama, Y.; Tanaka, T.; Tajima, H.; Bechtol, K.; Funk, S.; Lande, J.; Ballet, J.; Hanabata, Y.; Lemoine-Goumard, M.; Takahashi, T.; /JAXA, Sagamihara</p> <p>2012-08-17</p> <p>We present an analysis of gamma-ray data obtained with the Large Area Telescope (<span class="hlt">LAT</span>) onboard the Fermi Gamma-ray Space Telescope in the region around SNR S147 (G180.0-1.7). A spatially extended gamma-ray source detected in an energy range of 0.2-10 GeV is found to coincide with SNR S147. We confirm its spatial extension at >5{sigma} confidence level. The gamma-ray <span class="hlt">flux</span> is (3.8 {+-} 0.6) x 10{sup -8} photons cm{sup -2} s{sup -1}, corresponding to a luminosity of 1.3 x 10{sup 34} (d/1.3 kpc){sup 2} erg s{sup -1} in this energy range. The gamma-ray emission exhibits a possible spatial correlation with prominent H{alpha} filaments of S147. There is no indication that the gamma-ray emission comes from the associated pulsar PSR J0538+2817. The gamma-ray spectrum integrated over the remnant is likely dominated by the decay of neutral {pi} mesons produced through the proton-proton collisions in the filaments. Reacceleration of pre-existing CRs and subsequent adiabatic compression in the filaments is sufficient to provide the required energy density of high-energy protons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1258662','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1258662"><span>The first <i>Fermi</i> <span class="hlt">LAT</span> supernova remnant catalog</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Acero, F.</p> <p>2016-05-16</p> <p>To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the <i>Fermi</i> Large Area Telescope. Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 <span class="hlt">flux</span> upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude, allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic <i>Fermi</i> <span class="hlt">LAT</span> analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, demonstrates the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. As a result, we model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1258662','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1258662"><span>The first <i>Fermi</i> <span class="hlt">LAT</span> supernova remnant catalog</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Acero, F.</p> <p>2016-05-16</p> <p>To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the <i>Fermi</i> Large Area Telescope. Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 <span class="hlt">flux</span> upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude, allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic <i>Fermi</i> <span class="hlt">LAT</span> analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, demonstrates the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. As a result, we model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Ge%26Ae..57....8M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Ge%26Ae..57....8M"><span>Prediction of relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> in the Earth's outer radiation belt at geostationary orbit by adaptive methods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Myagkova, I. N.; Dolenko, S. A.; Efitorov, A. O.; Shirokii, V. R.; Sentemova, N. S.</p> <p>2017-01-01</p> <p>The paper investigates the possibilities of the prediction of the time series of the <span class="hlt">flux</span> of relativistic <span class="hlt">electrons</span> in the Earth's outer radiation belt by parameters of the solar wind and the interplanetary magnetic field measured at the libration point and by the values of the geomagnetic indices. Different adaptive methods are used (namely, artificial neural networks, group method of data handling, and projection to latent structures). The comparison of quality indicators of predictions with a horizon of 1-12 h between each other and with the trivial model prediction has shown that the best result is obtained for the average value of the responses of three neural networks that have been trained with different sets of initial weights. The prediction result of the group method of data handling is close to the result of neural networks, and the projection to latent structures is much worse. It is shown that an increase in the prediction horizon from 1 to 12 h reduces its quality but not dramatically, which makes it possible to use these methods for medium-term prediction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/940139','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/940139"><span>Fast Ignition relevant study of the <span class="hlt">flux</span> of high intensity laser generated <span class="hlt">electrons</span> via a hollow cone into a laser-imploded plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Key, M; Adam, J; Akli, K; Borgheshi, M; Chen, M; Evans, R; Freeman, R; Hatchett, S; Hill, J; Heron, A; King, J; Lancaster, K; Mackinnon, A; Norreys, P; Phillips, T; Romagnani, L; Snavely, R; Stephens, R; Stoeckl, C</p> <p>2005-10-11</p> <p>An integrated experiment relevant to fast ignition is described. A Cu doped CD spherical shell target is imploded around an inserted hollow Au cone by a six beam 600J, 1ns laser to a peak density of 4gcm{sup -3} and a diameter of 100 {micro}m. A 10 ps, 20TW laser pulse is focused into the cone at the time of peak compression. The <span class="hlt">flux</span> of high-energy <span class="hlt">electrons</span> through the imploded material is determined from the yield of Cu K{alpha} fluorescence by comparison with a Monte Carlo model and is estimated to carry 15% of the laser energy. Collisional and Ohmic heating are modeled. An <span class="hlt">electron</span> spectrometer shows significantly greater reduction of the transmitted <span class="hlt">electron</span> <span class="hlt">flux</span> than is due to binary collisions and Ohmic potential. Enhanced scattering by instability-induced magnetic fields is suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26831831','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26831831"><span>Persistent current in a correlated quantum ring with <span class="hlt">electron</span>-phonon interaction in the presence of Rashba interaction and Aharonov-Bohm <span class="hlt">flux</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Monisha, P J; Sankar, I V; Sil, Shreekantha; Chatterjee, Ashok</p> <p>2016-02-01</p> <p>Persistent current in a correlated quantum ring threaded by an Aharonov-Bohm <span class="hlt">flux</span> is studied in the presence of <span class="hlt">electron</span>-phonon interactions and Rashba spin-orbit coupling. The quantum ring is modeled by the Holstein-Hubbard-Rashba Hamiltonian and the energy is calculated by performing the conventional Lang-Firsov transformation followed by the diagonalization of the effective Hamiltonian within a mean-field approximation. The effects of Aharonov-Bohm <span class="hlt">flux</span>, temperature, spin-orbit and <span class="hlt">electron</span>-phonon interactions on the persistent current are investigated. It is shown that the <span class="hlt">electron</span>-phonon interactions reduce the persistent current, while the Rashba coupling enhances it. It is also shown that temperature smoothens the persistent current curve. The effect of chemical potential on the persistent current is also studied.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4735522','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4735522"><span>Persistent current in a correlated quantum ring with <span class="hlt">electron</span>-phonon interaction in the presence of Rashba interaction and Aharonov-Bohm <span class="hlt">flux</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Monisha, P. J.; Sankar, I. V.; Sil, Shreekantha; Chatterjee, Ashok</p> <p>2016-01-01</p> <p>Persistent current in a correlated quantum ring threaded by an Aharonov-Bohm <span class="hlt">flux</span> is studied in the presence of <span class="hlt">electron</span>-phonon interactions and Rashba spin-orbit coupling. The quantum ring is modeled by the Holstein-Hubbard-Rashba Hamiltonian and the energy is calculated by performing the conventional Lang-Firsov transformation followed by the diagonalization of the effective Hamiltonian within a mean-field approximation. The effects of Aharonov-Bohm <span class="hlt">flux</span>, temperature, spin-orbit and <span class="hlt">electron</span>-phonon interactions on the persistent current are investigated. It is shown that the <span class="hlt">electron</span>-phonon interactions reduce the persistent current, while the Rashba coupling enhances it. It is also shown that temperature smoothens the persistent current curve. The effect of chemical potential on the persistent current is also studied. PMID:26831831</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25870599','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25870599"><span>GRB2 Nucleates T Cell Receptor-Mediated <span class="hlt">LAT</span> Clusters That Control PLC-γ1 Activation and Cytokine Production.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bilal, Mahmood Yousif; Houtman, Jon C D</p> <p>2015-01-01</p> <p>GRB2 is a ubiquitously expressed adaptor protein required for signaling downstream of multiple receptors. To address the role of GRB2 in receptor-mediated signaling, the expression of GRB2 was suppressed in human CD4+ T cells and its role downstream of the T cell receptor (TCR) was examined. Interestingly, GRB2 deficient T cells had enhanced signaling from complexes containing the TCR. However, GRB2 deficient T cells had substantially reduced production of IL-2 and IFN-γ. This defect was attributed to diminished formation of linker for activation of T cells (<span class="hlt">LAT</span>) signaling clusters, which resulted in reduced MAP kinase activation, calcium <span class="hlt">flux</span>, and PLC-γ1 recruitment to <span class="hlt">LAT</span> signaling clusters. Add back of wild-type GRB2, but not a novel N-terminal SH3 domain mutant, rescued <span class="hlt">LAT</span> microcluster formation, calcium mobilization, and cytokine release, providing the first direct evidence that GRB2, and its ability to bind to SH3 domain ligands, is required for establishing <span class="hlt">LAT</span> microclusters. Our data demonstrate that the ability of GRB2 to facilitate protein clusters is equally important in regulating TCR-mediated functions as its capacity to recruit effector proteins. This highlights that GRB2 regulates signaling downstream of adaptors and receptors by both recruiting effector proteins and regulating the formation of signaling complexes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4378308','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4378308"><span>GRB2 Nucleates T Cell Receptor-Mediated <span class="hlt">LAT</span> Clusters That Control PLC-γ1 Activation and Cytokine Production</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bilal, Mahmood Yousif; Houtman, Jon C. D.</p> <p>2015-01-01</p> <p>GRB2 is a ubiquitously expressed adaptor protein required for signaling downstream of multiple receptors. To address the role of GRB2 in receptor-mediated signaling, the expression of GRB2 was suppressed in human CD4+ T cells and its role downstream of the T cell receptor (TCR) was examined. Interestingly, GRB2 deficient T cells had enhanced signaling from complexes containing the TCR. However, GRB2 deficient T cells had substantially reduced production of IL-2 and IFN-γ. This defect was attributed to diminished formation of linker for activation of T cells (<span class="hlt">LAT</span>) signaling clusters, which resulted in reduced MAP kinase activation, calcium <span class="hlt">flux</span>, and PLC-γ1 recruitment to <span class="hlt">LAT</span> signaling clusters. Add back of wild-type GRB2, but not a novel N-terminal SH3 domain mutant, rescued <span class="hlt">LAT</span> microcluster formation, calcium mobilization, and cytokine release, providing the first direct evidence that GRB2, and its ability to bind to SH3 domain ligands, is required for establishing <span class="hlt">LAT</span> microclusters. Our data demonstrate that the ability of GRB2 to facilitate protein clusters is equally important in regulating TCR-mediated functions as its capacity to recruit effector proteins. This highlights that GRB2 regulates signaling downstream of adaptors and receptors by both recruiting effector proteins and regulating the formation of signaling complexes. PMID:25870599</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..APR.E7006Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..APR.E7006Y"><span>Nu<span class="hlt">Lat</span>: 3D Event Reconstruction of a ROL Detector for Neutrino Detection and Background Rejection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yokley, Zachary; NuLat Collaboration</p> <p>2015-04-01</p> <p>Nu<span class="hlt">Lat</span> is a proposed very-short baseline reactor antineutrino experiment that employs a unique detector design, a Ragahavan Optical Lattice (ROL), developed for the LENS solar neutrino experiment. The 3D lattice provides high spatial and temporal resolution and allows for energy deposition in each voxel to be determined independently of other voxels, as well as the time sequence associated with each voxel energy deposition. This unique feature arises from two independent means to spatially locate energy deposits: via timing and via optical channeling. Nu<span class="hlt">Lat</span>, the first application of a ROL detector targeting physics results, will measure the reactor antineutrino <span class="hlt">flux</span> at very short baselines via inverse beta decay (IBD). The ROL design of Nu<span class="hlt">Lat</span> makes possible the reconstruction of positron energy with little contamination due to the annihilation gammas which smear the positron energy resolution in a traditional detector. IBD events are cleanly tagged via temporal and spatial coincidence of neutron capture in the vertex voxel or nearest neighbors. This talk will present work on IBD event reconstruction in Nu<span class="hlt">Lat</span> and its likely impact on sterile neutrino detection via operation in higher background locations enabled by its superior rejection of backgrounds. This research has been funded in part by the National Science Foundation on Award Numbers 1001394 and 1001078.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013IAUS..291...81S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013IAUS..291...81S"><span>Fermi-<span class="hlt">LAT</span> searches for γ-ray pulsars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saz Parkinson, P. M.; Fermi LAT Collaboration</p> <p>2013-03-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on the Fermi satellite is the first γ-ray instrument to discover pulsars directly via their γ-ray emission. Roughly one third of the 117 γ-ray pulsars detected by the <span class="hlt">LAT</span> in its first three years were discovered in blind searches of γ-ray data and most of these are undetectable with current radio telescopes. I review some of the key <span class="hlt">LAT</span> results and highlight the specific challenges faced in γ-ray (compared to radio) searches, most of which stem from the long, sparse data sets and the broad, energy-dependent point-spread function (PSF) of the <span class="hlt">LAT</span>. I discuss some ongoing <span class="hlt">LAT</span> searches for γ-ray millisecond pulsars (MSPs) and γ-ray pulsars around the Galactic Center. Finally, I outline the prospects for future γ-ray pulsar discoveries as the <span class="hlt">LAT</span> enters its extended mission phase, including advantages of a possible modification of the <span class="hlt">LAT</span> observing profile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014A%26A...562A.145H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014A%26A...562A.145H"><span>Search for extended γ-ray emission around AGN with H.E.S.S. and Fermi-<span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>H. E. S. S. Collaboration; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Angüner, E.; Anton, G.; Backes, M.; Balenderan, S.; Balzer, A.; Barnacka, A.; Becherini, Y.; Becker Tjus, J.; Bernlöhr, K.; Birsin, E.; Bissaldi, E.; Biteau, J.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Brucker, J.; Brun, F.; Brun, P.; Bulik, T.; Carrigan, S.; Casanova, S.; Chadwick, P. M.; Chalme-Calvet, R.; Chaves, R. C. G.; Cheesebrough, A.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Conrad, J.; Couturier, C.; Cui, Y.; Dalton, M.; Daniel, M. K.; Davids, I. D.; Degrange, B.; Deil, C.; deWilt, P.; Dickinson, H. J.; Djannati-Atäı, A.; Domainko, W.; Drury, L. O'C.; Dubus, G.; Dutson, K.; Dyks, J.; Dyrda, M.; Edwards, T.; Egberts, K.; Eger, P.; Espigat, P.; Farnier, C.; Fegan, S.; Feinstein, F.; Fernandes, M. V.; Fernandez, D.; Fiasson, A.; Fontaine, G.; Förster, A.; Füßling, M.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Grondin, M.-H.; Grudzińska, M.; Häffner, S.; Hahn, J.; Harris, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hillert, A.; Hinton, J. A.; Hofmann, W.; Hofverberg, P.; Holler, M.; Horns, D.; Jacholkowska, A.; Jahn, C.; Jamrozy, M.; Janiak, M.; Jankowsky, F.; Jung, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kaufmann, S.; Khélifi, B.; Kieffer, M.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kneiske, T.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lefaucheur, J.; Lemie`re, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Lohse, T.; Lopatin, A.; Lu, C.-C.; Marandon, V.; Marcowith, A.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; McComb, T. J. L.; Méhault, J.; Meintjes, P. J.; Menzler, U.; Meyer, M.; Moderski, R.; Mohamed, M.; Moulin, E.; Murach, T.; Naumann, C. L.; de Naurois, M.; Niemiec, J.; Nolan, S. J.; Oakes, L.; Odaka, H.; Ohm, S.; de Oña Wilhelmi, E.; Opitz, B.; Ostrowski, M.; Oya, I.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perez, J.; Petrucci, P.-O.; Peyaud, B.; Pita, S.; Poon, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Raue, M.; Reichardt, I.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Rob, L.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Sanchez, D. A.; Santangelo, A.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Sol, H.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tluczykont, M.; Trichard, C.; Valerius, K.; van Eldik, C.; van Soelen, B.; Vasileiadis, G.; Venter, C.; Viana, A.; Vincent, P.; Völk, H. J.; Volpe, F.; Vorster, M.; Vuillaume, T.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; Ward, M.; Weidinger, M.; Weitzel, Q.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zacharias, M.; Zdziarski, A. A.; Zech, A.; Zechlin, H.-S.; Malyshev, D.</p> <p>2014-02-01</p> <p>Context. Very-high-energy (VHE; E > 100 GeV) γ-ray emission from blazars inevitably gives rise to <span class="hlt">electron</span>-positron pair production through the interaction of these γ-rays with the extragalactic background light (EBL). Depending on the magnetic fields in the proximity of the source, the cascade initiated from pair production can result in either an isotropic halo around an initially beamed source or a magnetically broadened cascade <span class="hlt">flux</span>. Aims: Both extended pair-halo (PH) and magnetically broadened cascade (MBC) emission from regions surrounding the blazars 1ES 1101-232, 1ES 0229+200, and PKS 2155-304 were searched for using VHE γ-ray data taken with the High Energy Stereoscopic System (H.E.S.S.) and high-energy (HE; 100 MeV < E < 100 GeV) γ-ray data with the Fermi Large Area Telescope (<span class="hlt">LAT</span>). Methods: By comparing the angular distributions of the reconstructed γ-ray events to the angular profiles calculated from detailed theoretical models, the presence of PH and MBC was investigated. Results: Upper limits on the extended emission around 1ES 1101-232, 1ES 0229+200, and PKS 2155-304 are found to be at a level of a few per cent of the Crab nebula <span class="hlt">flux</span> above 1 TeV, depending on the assumed photon index of the cascade emission. Assuming strong extra-Galactic magnetic field (EGMF) values, >10-12 G, this limits the production of pair haloes developing from electromagnetic cascades. For weaker magnetic fields, in which electromagnetic cascades would result in MBCs, EGMF strengths in the range (0.3-3)× 10-15 G were excluded for PKS 2155-304 at the 99% confidence level, under the assumption of a 1 Mpc coherence length.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SpWea..14...22B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SpWea..14...22B"><span>Comparative analysis of NOAA REFM and SNB3GEO tools for the forecast of the <span class="hlt">fluxes</span> of high-energy <span class="hlt">electrons</span> at GEO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Balikhin, M. A.; Rodriguez, J. V.; Boynton, R. J.; Walker, S. N.; Aryan, H.; Sibeck, D. G.; Billings, S. A.</p> <p>2016-01-01</p> <p>Reliable forecasts of relativistic <span class="hlt">electrons</span> at geostationary orbit (GEO) are important for the mitigation of their hazardous effects on spacecraft at GEO. For a number of years the Space Weather Prediction Center at NOAA has provided advanced online forecasts of the fluence of <span class="hlt">electrons</span> with energy >2 MeV at GEO using the Relativistic <span class="hlt">Electron</span> Forecast Model (REFM). The REFM forecasts are based on real-time solar wind speed observations at L1. The high reliability of this forecasting tool serves as a benchmark for the assessment of other forecasting tools. Since 2012 the Sheffield SNB3GEO model has been operating online, providing a 24 h ahead forecast of the same <span class="hlt">fluxes</span>. In addition to solar wind speed, the SNB3GEO forecasts use solar wind density and interplanetary magnetic field Bz observations at L1.The period of joint operation of both of these forecasts has been used to compare their accuracy. Daily averaged measurements of <span class="hlt">electron</span> <span class="hlt">fluxes</span> by GOES 13 have been used to estimate the prediction efficiency of both forecasting tools. To assess the reliability of both models to forecast infrequent events of very high <span class="hlt">fluxes</span>, the Heidke skill score was employed. The results obtained indicate that SNB3GEO provides a more accurate 1 day ahead forecast when compared to REFM. It is shown that the correction methodology utilized by REFM potentially can improve the SNB3GEO forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CosRe..55...72M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CosRe..55...72M"><span>Dynamics of <span class="hlt">electron</span> <span class="hlt">fluxes</span> in the slot between radiation belts in November-December 2014 according to data of the Vernov satellite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Myagkova, I. N.; Svertilov, S. I.; Kovtyukh, A. S.; Bogomolov, V. V.; Bogomolov, A. V.; Panasyuk, M. I.; Sibiryakova, D. V.; Balan, E. V.</p> <p>2017-01-01</p> <p>The variations in the spatial structure and time in <span class="hlt">electron</span> <span class="hlt">fluxes</span> with E = 235-300 keV in the slot region (2 < L < 3) between the radiation belts in the period of November 1, 2014 through December 8, 2014 during weak and moderate geomagnetic disturbances ( Kp < 4, Dst >-60 nT) are analyzed based on the data of the RELEC complex on board the Vernov satellite (the height and inclination of the orbit are from 640 to 830 km and 98.4°, respectively). Irregular increases in the <span class="hlt">fluxes</span> of such <span class="hlt">electrons</span> and formation of a local maximum at L 2.2-3.0 were observed. It has been shown that the intensity of this maximum is inversely proportional to the L value and grows with an increase in the geomagnetic activity level. New features discovered for the first time in the dynamics of radiation belt <span class="hlt">electrons</span> manifest in the variations in the local structure and dynamics of <span class="hlt">fluxes</span> of subrelativistic <span class="hlt">electrons</span> in the slot region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E2014V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E2014V"><span>Comparative dynamics of relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> during two geomagnetic storms on 17-18 March and on 22-23 June 22-23 in 2015</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vlasova, Natalia; Kalegaev, Vladimir; Beresneva, Evgeniya; Stanislav, Ganitskiy</p> <p>2016-07-01</p> <p>The role of solar wind in the outer Earth`s radiation belt dynamics is under consideration during the last decades. Unfortunately, the physical mechanisms that control the loss and acceleration of the magnetospheric relativistic <span class="hlt">electron</span> <span class="hlt">fluxes</span> are not evident until now. In this study we compared and contrasted some features of relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> dynamics during two largest geomagnetic storms in 2015 (17-18 March and 22-23 June) having the similar Dst-variations profiles and amplitudes (~200 nT). Analysis of experimental data from Van Allen Probes (RBSP), GOES, Electro, POES, Meteor satellites was combined with theoretical investigations on the base of the A2000 model of the magnetospheric magnetic field. Multipoint observations at GEO and LEO show the dramatic changes in the MeV <span class="hlt">electron</span> populations during the main phase of the magnetic storms. We found the solar wind and IMF variations responsible for large-scale magnetospheric current system changes that reveal themselves in the relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27642268','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27642268"><span>Comparative analysis of NOAA REFM and SNB(3)GEO tools for the forecast of the <span class="hlt">fluxes</span> of high-energy <span class="hlt">electrons</span> at GEO.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Balikhin, M A; Rodriguez, J V; Boynton, R J; Walker, S N; Aryan, H; Sibeck, D G; Billings, S A</p> <p>2016-01-01</p> <p>Reliable forecasts of relativistic <span class="hlt">electrons</span> at geostationary orbit (GEO) are important for the mitigation of their hazardous effects on spacecraft at GEO. For a number of years the Space Weather Prediction Center at NOAA has provided advanced online forecasts of the fluence of <span class="hlt">electrons</span> with energy >2 MeV at GEO using the Relativistic <span class="hlt">Electron</span> Forecast Model (REFM). The REFM forecasts are based on real-time solar wind speed observations at L1. The high reliability of this forecasting tool serves as a benchmark for the assessment of other forecasting tools. Since 2012 the Sheffield SNB(3)GEO model has been operating online, providing a 24 h ahead forecast of the same <span class="hlt">fluxes</span>. In addition to solar wind speed, the SNB(3)GEO forecasts use solar wind density and interplanetary magnetic field Bz observations at L1.The period of joint operation of both of these forecasts has been used to compare their accuracy. Daily averaged measurements of <span class="hlt">electron</span> <span class="hlt">fluxes</span> by GOES 13 have been used to estimate the prediction efficiency of both forecasting tools. To assess the reliability of both models to forecast infrequent events of very high <span class="hlt">fluxes</span>, the Heidke skill score was employed. The results obtained indicate that SNB(3)GEO provides a more accurate 1 day ahead forecast when compared to REFM. It is shown that the correction methodology utilized by REFM potentially can improve the SNB(3)GEO forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170003242&hterms=Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DEnergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170003242&hterms=Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DEnergy"><span>Comparative Analysis of NOAA REFM and SNB3GEO Tools for the Forecast of the <span class="hlt">Fluxes</span> of High-Energy <span class="hlt">Electrons</span> at GEO</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Balikhin, M. A.; Rodriguez, J. V.; Boynton, R. J.; Walker, S. N.; Aryan, Homayon; Sibeck, D. G.; Billings, S. A.</p> <p>2016-01-01</p> <p>Reliable forecasts of relativistic <span class="hlt">electrons</span> at geostationary orbit (GEO) are important for the mitigation of their hazardous effects on spacecraft at GEO. For a number of years the Space Weather Prediction Center at NOAA has provided advanced online forecasts of the fluence of <span class="hlt">electrons</span> with energy >2 MeV at GEO using the Relativistic <span class="hlt">Electron</span> Forecast Model (REFM). The REFM forecasts are based on real-time solar wind speed observations at L1. The high reliability of this forecasting tool serves as a benchmark for the assessment of other forecasting tools. Since 2012 the Sheffield SNB3GEO model has been operating online, providing a 24 h ahead forecast of the same <span class="hlt">fluxes</span>. In addition to solar wind speed, the SNB3GEO forecasts use solar wind density and interplanetary magnetic field B(sub z) observations at L1. The period of joint operation of both of these forecasts has been used to compare their accuracy. Daily averaged measurements of <span class="hlt">electron</span> <span class="hlt">fluxes</span> by GOES 13 have been used to estimate the prediction efficiency of both forecasting tools. To assess the reliability of both models to forecast infrequent events of very high <span class="hlt">fluxes</span>, the Heidke skill score was employed. The results obtained indicate that SNB3GEO provides a more accurate 1 day ahead forecast when compared to REFM. It is shown that the correction methodology utilized by REFM potentially can improve the SNB3GEO forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22522435','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22522435"><span>A STACKED ANALYSIS OF 115 PULSARS OBSERVED BY THE FERMI <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>McCann, A.</p> <p>2015-05-10</p> <p>Due to the low gamma-ray <span class="hlt">fluxes</span> from pulsars above 50 GeV and the small collecting area of space-based telescopes, the gamma-ray emission discovered by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) in ∼150 pulsars is largely unexplored at these energies. In this regime, the uncertainties on the spectral data points and/or the constraints from upper limits are not sufficient to provide robust tests of competing emission models in individual pulsars. The discovery of power-law-type emission from the Crab pulsar at energies exceeding 100 GeV provides a compelling justification for exploration of other pulsars at these energies. We applied the method of aperture photometry to measure pulsar emission spectra from Fermi-<span class="hlt">LAT</span> data and present a stacked analysis of 115 pulsars selected from the Second Fermi-<span class="hlt">LAT</span> catalog of gamma-ray pulsars. This analysis, which uses an average of ∼4.2 yr of data per pulsar, aggregates low-level emission which cannot be resolved in individual objects but can be detected in an ensemble. We find no significant stacked excess at energies above 50 GeV. An upper limit of 30% of the Crab pulsar level is found for the average <span class="hlt">flux</span> from 115 pulsars in the 100–177 GeV energy range at the 95% confidence level. Stacked searches exclusive to the young pulsar sample, the millisecond pulsar sample, and several other promising sub-samples also return no significant excesses above 50 GeV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120001991&hterms=nuclei&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dnuclei','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120001991&hterms=nuclei&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dnuclei"><span>Fermi/<span class="hlt">LAT</span> Observations of Swift/BAT Seyfert Galaxies: On the Contribution of Radio-Quiet Active Galactic Nuclei to the Extragalactic gamma-Ray Background</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Teng, Stacy H.; Mushotzky, Richard F.; Sambruna, Rita M.; Davis, David S.; Reynolds, Christopher S.</p> <p>2011-01-01</p> <p>We present the analysis of 2.1 years of Fermi Large Area Telescope (<span class="hlt">LAT</span>) data on 491 Seyfert galaxies detected by the Swift Burst Alert Telescope (BAT) survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi first year catalog, are detected. Using Swift/BAT and radio 20 cm <span class="hlt">fluxes</span>, we define a new radio-loudness parameter R(sub X,BAT) where radio-loud objects have logR(sub X,BAT) > -4.7. Based on this parameter, only radio-loud sources are detected by Fermi/<span class="hlt">LAT</span>. An upper limit to the <span class="hlt">flux</span> of the undetected sources is derived to be approx.2x10(exp -11) photons/sq cm/s, approximately seven times lower than the observed <span class="hlt">flux</span> of NGC 1068. Assuming a median redshift of 0.031, this implies an upper limit to the gamma-ray (1-100 GeV) luminosity of < approx.3x10(exp 41) erg/s. In addition, we identified 120 new Fermi/<span class="hlt">LAT</span> sources near the Swift/BAT Seyfert galaxies with significant Fermi/<span class="hlt">LAT</span> detections. A majority of these objects do not have Swift/BAT counterparts, but their possible optical counterparts include blazars, flat-spectrum radio quasars, and quasars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120001991&hterms=Nucleus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DNucleus','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120001991&hterms=Nucleus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DNucleus"><span>Fermi/<span class="hlt">LAT</span> Observations of Swift/BAT Seyfert Galaxies: On the Contribution of Radio-Quiet Active Galactic Nuclei to the Extragalactic gamma-Ray Background</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Teng, Stacy H.; Mushotzky, Richard F.; Sambruna, Rita M.; Davis, David S.; Reynolds, Christopher S.</p> <p>2011-01-01</p> <p>We present the analysis of 2.1 years of Fermi Large Area Telescope (<span class="hlt">LAT</span>) data on 491 Seyfert galaxies detected by the Swift Burst Alert Telescope (BAT) survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi first year catalog, are detected. Using Swift/BAT and radio 20 cm <span class="hlt">fluxes</span>, we define a new radio-loudness parameter R(sub X,BAT) where radio-loud objects have logR(sub X,BAT) > -4.7. Based on this parameter, only radio-loud sources are detected by Fermi/<span class="hlt">LAT</span>. An upper limit to the <span class="hlt">flux</span> of the undetected sources is derived to be approx.2x10(exp -11) photons/sq cm/s, approximately seven times lower than the observed <span class="hlt">flux</span> of NGC 1068. Assuming a median redshift of 0.031, this implies an upper limit to the gamma-ray (1-100 GeV) luminosity of < approx.3x10(exp 41) erg/s. In addition, we identified 120 new Fermi/<span class="hlt">LAT</span> sources near the Swift/BAT Seyfert galaxies with significant Fermi/<span class="hlt">LAT</span> detections. A majority of these objects do not have Swift/BAT counterparts, but their possible optical counterparts include blazars, flat-spectrum radio quasars, and quasars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22004651','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22004651"><span>FERMI/<span class="hlt">LAT</span> OBSERVATIONS OF SWIFT/BAT SEYFERT GALAXIES: ON THE CONTRIBUTION OF RADIO-QUIET ACTIVE GALACTIC NUCLEI TO THE EXTRAGALACTIC {gamma}-RAY BACKGROUND</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Teng, Stacy H.; Mushotzky, Richard F.; Reynolds, Christopher S.; Sambruna, Rita M.; Davis, David S.</p> <p>2011-12-01</p> <p>We present the analysis of 2.1 years of Fermi Large Area Telescope (<span class="hlt">LAT</span>) data on 491 Seyfert galaxies detected by the Swift Burst Alert Telescope (BAT) survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi first year catalog, are detected. Using Swift/BAT and radio 20 cm <span class="hlt">fluxes</span>, we define a new radio-loudness parameter R{sub X,BAT} where radio-loud objects have log R{sub X,BAT} > -4.7. Based on this parameter, only radio-loud sources are detected by Fermi/<span class="hlt">LAT</span>. An upper limit to the <span class="hlt">flux</span> of the undetected sources is derived to be {approx}2 Multiplication-Sign 10{sup -11} photons cm{sup -2} s{sup -1}, approximately seven times lower than the observed <span class="hlt">flux</span> of NGC 1068. Assuming a median redshift of 0.031, this implies an upper limit to the {gamma}-ray (1-100 GeV) luminosity of {approx}< 3 Multiplication-Sign 10{sup 41} erg s{sup -1}. In addition, we identified 120 new Fermi/<span class="hlt">LAT</span> sources near the Swift/BAT Seyfert galaxies with significant Fermi/<span class="hlt">LAT</span> detections. A majority of these objects do not have Swift/BAT counterparts, but their possible optical counterparts include blazars, flat-spectrum radio quasars, and quasars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AAS...22740305O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AAS...22740305O"><span>Pushing the Limits: High Redshift Fermi-<span class="hlt">LAT</span> Blazars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ojha, Roopesh; Gasparrini, Dario; Lott, Benoit; Cutini, Sara; Fermi-LAT Collaboration</p> <p>2016-01-01</p> <p>High-redshift blazars detected by the Fermi Large Area Telescope (<span class="hlt">LAT</span>) are of great astrophysical import as they are extreme objects whose energetics remain a mystery. Such blazars are intrinsically interesting since they inform us about the evolution of gamma-ray blazars and are, by definition, some of the more luminous blazars in the <span class="hlt">LAT</span> sample. They are also an excellent tool to study the EBL and thus the gamma-ray horizon. We present the latest high redshift blazar detections in the <span class="hlt">LAT</span> and discuss some of their implications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/50533','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/50533"><span>Relationship between energy <span class="hlt">flux</span> Q and mean energy <E> of auroral <span class="hlt">electron</span> spectra based on radar data from the 1987 CEDAR Campaign at Sondre Stromfjord, Greenland</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Strickland, D.J.; Hecht, J.H.; Christensen, A.B.; Kelly, J.</p> <p>1994-10-01</p> <p>The incoherent scatter radar at Sondre Stromfjord, Greenland, measured <span class="hlt">electron</span> density profiles from 90 to 500 km during four auroral events over a 3-hour period on February 28, 1987. The profiles were obtained with the radar pointed along the magnetic field near zenith at 15-s intervals. Under the assumption that proton/H atom precipitation was unimportant during these events a representation of the incident <span class="hlt">electron</span> <span class="hlt">flux</span> was obtained by fitting calculated profiles with measured profiles in the vicinity of their peaks (lower E region). Maxwellian and Gaussian <span class="hlt">electron</span> distributions with high- and low-energy tails were used to generate the calculated profiles. The distributions were specified in terms of average energy <E> and energy <span class="hlt">flux</span> Q. The authors find that they can clearly distinguish between profiles that result from a Maxwellian incident <span class="hlt">electron</span> spectrum and those that result from a Gaussian spectrum. Interpreting Gaussian and Maxwellian spectra as representative of discrete and diffuse aurora, respectively, the measurements indicated good correlation between <E> and Q for discrete aurora, while essentially no correlation was observed for diffuse aurora. This is consistent with current understanding that discrete auroras are produced by <span class="hlt">electrons</span> accelerated by magnetic field-aligned potential drops whereas diffuse auroras are produced by pitch angle diffusion of plasma sheet <span class="hlt">electrons</span> into the loss cone. 27 refs., 8 figs., 2 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017HEAD...1610638C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017HEAD...1610638C"><span>Searches for Angular Extension in High Latitude Fermi-<span class="hlt">LAT</span> Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caputo, Regina; Di Mauro, Mattia; Meyer, Manuel; Wood, Matthew; Biteau, Jonathan</p> <p>2017-08-01</p> <p>We report on the Fermi High-Latitude Extended Sources Catalog (FHES), a comprehensive search for spatially extended gamma-ray sources at high Galactic latitudes based on data from the Fermi Large Area Telescope (<span class="hlt">LAT</span>). While the majority of high-latitude <span class="hlt">LAT</span> sources are extragalactic blazars that appear point-like within the <span class="hlt">LAT</span> angular resolution, there are several physics scenarios that predict the existence of populations of spatially extended sources. If Dark Matter (DM) consists of Weakly Interacting Massive Particles, the annihilation or decay of these particles in subhalos of the Milky Way would appear as a population of unassociated gamma-ray sources with finite angular extent. Gamma-ray emission from blazars could also be extended (so-called pair halos) due to the deflection of <span class="hlt">electron</span>-positron pairs in the intergalactic magnetic field (IGMF). The pairs are produced in the absorption of gamma rays in the intergalactic medium and subsequently up-scatter photons of background radiation fields to gamma-ray energies. Measurement of pair halos could provide constraints on the strength and coherence length scale of the IGMF. We report on new extended source candidates found in the FHES as well as constraints on extended emission from point-like sources and discuss the implications of these results in the context of searches for both DM subhalos and IGMF-induced pair halos.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19562367','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19562367"><span>Arginine transport in human erythroid cells: discrimination of CAT1 and 4F2hc/y+<span class="hlt">LAT</span>2 roles.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rotoli, Bianca Maria; Closs, Ellen I; Barilli, Amelia; Visigalli, Rossana; Simon, Alexandra; Habermeier, Alice; Bianchi, Nicoletta; Gambari, Roberto; Gazzola, Gian C; Bussolati, Ovidio; Dall'Asta, Valeria</p> <p>2009-10-01</p> <p>Since arginine metabolites, such as nitric oxide and polyamines, influence the expression of genes involved in erythroid differentiation, the transport of the cationic amino acid may play an important role in erythroid cells. However, available data only concern the presence in these cells of CAT1 transporter (system y(+)), while no information exists on the role of the heterodimeric transporters of system y(+)L (4F2hc/y(+)<span class="hlt">LAT</span>1 and 4F2hc/y(+)<span class="hlt">LAT</span>2) which operates transmembrane arginine <span class="hlt">fluxes</span> cis-inhibited by neutral amino acids in the presence of sodium. Using erythroleukemia K562 cells and normal erythroid precursors, we demonstrate here that arginine transport in human erythroid cells is due to the additive contributions of a leucine-sensitive and leucine-insensitive component. In both cell types, leucine inhibition of arginine influx is much less evident in the absence of sodium, a hallmark of system y(+)L. In K562 cells, N-ethylmaleimide, a known inhibitor of CAT transporters (system y(+)), suppresses only a fraction of arginine influx corresponding to leucine-insensitive uptake. Moreover, in Xenopus oocytes coexpressing 4F2hc and y(+)<span class="hlt">LAT</span>2, leucine exerts a marked inhibition of arginine transport, partially dependent on sodium, while no inhibition is seen in oocytes expressing CAT1. Lastly, silencing of SLC7A6, the gene for y(+)<span class="hlt">LAT</span>2, lowers arginine transport and doubles the intracellular content of the cationic amino acid in K562 cells. We conclude that arginine transport in human erythroid cells is due to both system y(+) (CAT1 transporter) and system y(+)L (4F2hc/y(+)<span class="hlt">LAT</span>2 isoform), which mainly contribute, respectively, to the influx and to the efflux of the cationic amino acid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150008355','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150008355"><span>Fermi-<span class="hlt">LAT</span> Detection of Gravitational Lens Delayed Gamma-Ray Flares from Blazar B0218+357</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cheung, C. C.; Larsson, S.; Scargle, J. D.; Amin, M. A.; Blandford, R. D.; Bulmash, D.; Chiang, J.; Ciprini, S.; Corbet, R. D. H.; Falco, E. E.; Marshall, P. J.; Wood, D. L.; Ajello, M.; Bastieri, D.; Chekhtman, A.; D'Ammando, F.; Giroletti, M.; Grove, J. E.; Lott, B.; Ohja, R.; Orienti, M.; Perkins, J. S.; Razzano, M.; Smith, A. W.; Thompson, D. J.; Wood, K. S.</p> <p>2014-01-01</p> <p>Using data from the Fermi Large Area Telescope (<span class="hlt">LAT</span>), we report the first clear gamma-ray measurement of a delay between flares from the gravitationally lensed images of a blazar. The delay was detected in B0218+357, a known double-image lensed system, during a period of enhanced gamma-ray activity with peak <span class="hlt">fluxes</span> consistently observed to reach greater than 20-50 times its previous average <span class="hlt">flux</span>. An auto-correlation function analysis identified a delay in the gamma-ray data of 11.46 plus or minus 0.16 days (1 sigma) that is approximately 1 day greater than previous radio measurements. Considering that it is beyond the capabilities of the <span class="hlt">LAT</span> to spatially resolve the two images, we nevertheless decomposed individual sequences of superposing gamma-ray flares/delayed emissions. In three such approximately 8-10 day-long sequences within an approximately 4-month span, considering confusion due to overlapping flaring emission and <span class="hlt">flux</span> measurement uncertainties, we found <span class="hlt">flux</span> ratios consistent with approximately 1, thus systematically smaller than those from radio observations. During the first, best-defined flare, the delayed emission was detailed with a Fermi pointing, and we observed <span class="hlt">flux</span> doubling timescales of approximately 3-6 hours implying as well extremely compact gamma-ray emitting regions.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5138187','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5138187"><span>Melatonin Increases the Chilling Tolerance of Chloroplast in Cucumber Seedlings by Regulating Photosynthetic <span class="hlt">Electron</span> <span class="hlt">Flux</span> and the Ascorbate-Glutathione Cycle</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhao, Hailiang; Ye, Lin; Wang, Yuping; Zhou, Xiaoting; Yang, Junwei; Wang, Jiawei; Cao, Kai; Zou, Zhirong</p> <p>2016-01-01</p> <p>The aim of the study was to monitor the effects of exogenous melatonin on cucumber (Cucumis sativus L.) chloroplasts and explore the mechanisms through which it mitigates chilling stress. Under chilling stress, chloroplast structure was seriously damaged as a result of over-accumulation of reactive oxygen species (ROS), as evidenced by the high levels of superoxide anion (O2−) and hydrogen peroxide (H2O2). However, pretreatment with 200 μM melatonin effectively mitigated this by suppressing the levels of ROS in chloroplasts. On the one hand, melatonin enhanced the scavenging ability of ROS by stimulating the ascorbate–glutathione (AsA–GSH) cycle in chloroplasts. The application of melatonin led to high levels of AsA and GSH, and increased the activity of total superoxide dismutase (SOD, EC 1.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11), monodehydroascorbate reductase (MDHAR, EC 1.6.5.4) dehydroascorbate reductase (DHAR, EC 1.5.5.1), glutathione reductase (GR, EC1.6.4.2) in the AsA–GSH cycle. On the other hand, melatonin lessened the production of ROS in chloroplasts by balancing the distribution of photosynthetic <span class="hlt">electron</span> <span class="hlt">flux</span>. Melatonin helped maintain a high level of <span class="hlt">electron</span> <span class="hlt">flux</span> in the PCR cycle [Je(PCR)] and in the PCO cycle [Je(PCO)], and suppressed the O2-dependent alternative <span class="hlt">electron</span> <span class="hlt">flux</span> Ja(O2-dependent) which is one important ROS source. Results indicate that melatonin increased the chilling tolerance of chloroplast in cucumber seedlings by accelerating the AsA–GSH cycle to enhance ROS scavenging ability and by balancing the distribution of photosynthetic <span class="hlt">electron</span> <span class="hlt">flux</span> so as to suppress ROS production. PMID:27999581</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ATel.2737....1D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ATel.2737....1D"><span>Fermi <span class="hlt">LAT</span> detection of gamma-ray flaring activity from the radio galaxy NGC 1275</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Donato, D.; Wood, D.; Cheung, C. C.</p> <p>2010-07-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed an increasing gamma-ray <span class="hlt">flux</span> from a source positionally consistent with NGC 1275 (1FGL J0319.7+4130, Abdo et al. 2010, ApJS, 188, 405), a radio galaxy located at the center of the Perseus cluster (see also Abdo et al. 2009, ApJ, 699, 31). Preliminary analysis indicates that the source began brightening on June 26, 2010 with a daily average gamma-ray <span class="hlt">flux</span> (E>100MeV) of (0.7 ±0.3) x 10-6 photons cm-2 s-1 (errors are statistical only).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1347934','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1347934"><span>Gamma-Ray Flaring Activity from the Gravitationally Lensed Blazar PKS 1830-211 Observed by Fermi <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.; et al.</p> <p>2015-01-23</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope routinely detects the MeV-peaked flat-spectrum radio quasar PKS 1830–211 (z = 2.507). Its apparent isotropic γ-ray luminosity (E > 100 MeV), averaged over ~3 years of observations and peaking on 2010 October 14/15 at 2.9 × 10(50) erg s(–)(1), makes it among the brightest high-redshift Fermi blazars. No published model with a single lens can account for all of the observed characteristics of this complex system. Based on radio observations, one expects time-delayed variability to follow about 25 days after a primary flare, with <span class="hlt">flux</span> about a factor of 1.5 less. Two large γ-ray flares of PKS 1830–211 have been detected by the <span class="hlt">LAT</span> in the considered period, and no substantial evidence for such a delayed activity was found. This allows us to place a lower limit of about 6 on the γ-ray <span class="hlt">flux</span> ratio between the two lensed images. Swift XRT observations from a dedicated Target of Opportunity program indicate a hard spectrum with no significant correlation of X-ray <span class="hlt">flux</span> with the γ-ray variability. The spectral energy distribution can be modeled with inverse Compton scattering of thermal photons from the dusty torus. The implications of the <span class="hlt">LAT</span> data in terms of variability, the lack of evident delayed flare events, and different radio and γ-ray <span class="hlt">flux</span> ratios are discussed. Microlensing effects, absorption, size and location of the emitting regions, the complex mass distribution of the system, an energy-dependent inner structure of the source, and <span class="hlt">flux</span> suppression by the lens galaxy for one image path may be considered as hypotheses for understanding our results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22364379','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22364379"><span>GAMMA-RAY FLARING ACTIVITY FROM THE GRAVITATIONALLY LENSED BLAZAR PKS 1830–211 OBSERVED BY Fermi <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.; Ackermann, M.; Buehler, R.; Ajello, M.; Allafort, A.; Bechtol, K.; Blandford, R. D.; Borgland, A. W.; Caliandro, G. A.; Cameron, R. A.; Amin, M. A.; Baldini, L.; Bellazzini, R.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bonamente, E.; Bregeon, J.; Bulmash, D. E-mail: stefano.ciprini@asdc.asi.it E-mail: dammando@ira.inaf.it E-mail: sara.buson@pd.infn.it E-mail: dammando@ira.inaf.it; and others</p> <p>2015-02-01</p> <p>The Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope routinely detects the MeV-peaked flat-spectrum radio quasar PKS 1830–211 (z = 2.507). Its apparent isotropic γ-ray luminosity (E > 100 MeV), averaged over ∼3 years of observations and peaking on 2010 October 14/15 at 2.9 × 10{sup 50} erg s{sup –1}, makes it among the brightest high-redshift Fermi blazars. No published model with a single lens can account for all of the observed characteristics of this complex system. Based on radio observations, one expects time-delayed variability to follow about 25 days after a primary flare, with <span class="hlt">flux</span> about a factor of 1.5 less. Two large γ-ray flares of PKS 1830–211 have been detected by the <span class="hlt">LAT</span> in the considered period, and no substantial evidence for such a delayed activity was found. This allows us to place a lower limit of about 6 on the γ-ray <span class="hlt">flux</span> ratio between the two lensed images. Swift XRT observations from a dedicated Target of Opportunity program indicate a hard spectrum with no significant correlation of X-ray <span class="hlt">flux</span> with the γ-ray variability. The spectral energy distribution can be modeled with inverse Compton scattering of thermal photons from the dusty torus. The implications of the <span class="hlt">LAT</span> data in terms of variability, the lack of evident delayed flare events, and different radio and γ-ray <span class="hlt">flux</span> ratios are discussed. Microlensing effects, absorption, size and location of the emitting regions, the complex mass distribution of the system, an energy-dependent inner structure of the source, and <span class="hlt">flux</span> suppression by the lens galaxy for one image path may be considered as hypotheses for understanding our results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1355169','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1355169"><span>Gamma-ray flaring activity from the gravitationally lensed blazar PKS 1830-211 observed by Fermi <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.; Ackermann, M.; Ajello, M.; Allafort, A.; Amin, M. A.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Blandford, R. D.; Bonamente, E.; Borgland, A. W.; Bregeon, J.; Brigida, M.; Buehler, R.; Bulmash, D.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cavazzuti, E.; Cecchi, C.; Charles, E.; Cheung, C. C.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Corbet, R. H. D.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Dermer, C. D.; Drell, P. S.; Drlica-Wagner, A.; Favuzzi, C.; Finke, J.; Focke, W. B.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Grenier, I. A.; Grove, J. E.; Guiriec, S.; Hadasch, D.; Hayashida, M.; Hays, E.; Hughes, R. E.; Inoue, Y.; Jackson, M. S.; Jogler, T.; Jóhannesson, G.; Johnson, A. S.; Kamae, T.; Knödlseder, J.; Kuss, M.; Lande, J.; Larsson, S.; Latronico, L.; Longo, F.; Loparco, F.; Lott, B.; Lovellette, M. N.; Lubrano, P.; Madejski, G. M.; Mazziotta, M. N.; Mehault, J.; Michelson, P. F.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nemmen, R.; Nuss, E.; Ohno, M.; Ohsugi, T.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Reyes, L. C.; Ritz, S.; Romoli, C.; Roth, M.; Saz Parkinson, P. M.; Sgrò, C.; Siskind, E. J.; Spandre, G.; Spinelli, P.; Takahashi, H.; Takeuchi, Y.; Tanaka, T.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Tinivella, M.; Torres, D. F.; Tosti, G.; Troja, E.; Tronconi, V.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vitale, V.; Waite, A. P.; Werner, M.; Winer, B. L.; Wood, K. S.</p> <p>2015-01-23</p> <p>We present that the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope routinely detects the MeV-peaked flat-spectrum radio quasar PKS 1830–211 (z = 2.507). Its apparent isotropic γ-ray luminosity (E > 100 MeV), averaged over ~3 years of observations and peaking on 2010 October 14/15 at 2.9 × 10<sup>50</sup> erg s<sup>–1</sup>, makes it among the brightest high-redshift Fermi blazars. No published model with a single lens can account for all of the observed characteristics of this complex system. Based on radio observations, one expects time-delayed variability to follow about 25 days after a primary flare, with <span class="hlt">flux</span> about a factor of 1.5 less. Two large γ-ray flares of PKS 1830–211 have been detected by the <span class="hlt">LAT</span> in the considered period, and no substantial evidence for such a delayed activity was found. This allows us to place a lower limit of about 6 on the γ-ray <span class="hlt">flux</span> ratio between the two lensed images. Swift XRT observations from a dedicated Target of Opportunity program indicate a hard spectrum with no significant correlation of X-ray <span class="hlt">flux</span> with the γ-ray variability. The spectral energy distribution can be modeled with inverse Compton scattering of thermal photons from the dusty torus. The implications of the <span class="hlt">LAT</span> data in terms of variability, the lack of evident delayed flare events, and different radio and γ-ray <span class="hlt">flux</span> ratios are discussed. Lastly, microlensing effects, absorption, size and location of the emitting regions, the complex mass distribution of the system, an energy-dependent inner structure of the source, and <span class="hlt">flux</span> suppression by the lens galaxy for one image path may be considered as hypotheses for understanding our results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...835...82R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...835...82R"><span>Searching the Gamma-Ray Sky for Counterparts to Gravitational Wave Sources: /Fermi GBM and <span class="hlt">LAT</span> Observations of LVT151012 and GW151226</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Racusin, J. L.; Burns, E.; Goldstein, A.; Connaughton, V.; Wilson-Hodge, C. A.; Jenke, P.; Blackburn, L.; Briggs, M. S.; Broida, J.; Camp, J.; Christensen, N.; Hui, C. M.; Littenberg, T.; Shawhan, P.; Singer, L.; Veitch, J.; Bhat, P. N.; Cleveland, W.; Fitzpatrick, G.; Gibby, M. H.; von Kienlin, A.; McBreen, S.; Mailyan, B.; Meegan, C. A.; Paciesas, W. S.; Preece, R. D.; Roberts, O. J.; Stanbro, M.; Veres, P.; Zhang, B.-B.; Fermi LAT Collaboration; Ackermann, M.; Albert, A.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Baring, M. G.; Bastieri, D.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bregeon, J.; Bruel, P.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caputo, R.; Caragiulo, M.; Caraveo, P. A.; Cavazzuti, E.; Charles, E.; Chiang, J.; Ciprini, S.; Costanza, F.; Cuoco, A.; Cutini, S.; D’Ammando, F.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Ferrara, E. C.; Focke, W. B.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Gill, R.; Giroletti, M.; Glanzman, T.; Granot, J.; Green, D.; Grove, J. E.; Guillemot, L.; Guiriec, S.; Harding, A. K.; Jogler, T.; Jóhannesson, G.; Kamae, T.; Kensei, S.; Kocevski, D.; Kuss, M.; Larsson, S.; Latronico, L.; Li, J.; Longo, F.; Loparco, F.; Lubrano, P.; Magill, J. D.; Maldera, S.; Malyshev, D.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Negro, M.; Nuss, E.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Principe, G.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Saz Parkinson, P. M.; Scargle, J. D.; Sgrò, C.; Simone, D.; Siskind, E. J.; Smith, D. A.; Spada, F.; Spinelli, P.; Suson, D. J.; Tajima, H.; Thayer, J. B.; Torres, D. F.; Troja, E.; Uchiyama, Y.; Vianello, G.; Wood, K. S.; Wood, M.</p> <p>2017-01-01</p> <p>We present the Fermi Gamma-ray Burst Monitor (GBM) and Large Area Telescope (<span class="hlt">LAT</span>) observations of the LIGO binary black hole merger event GW151226 and candidate LVT151012. At the time of the LIGO triggers on LVT151012 and GW151226, GBM was observing 68% and 83% of the localization regions, and <span class="hlt">LAT</span> was observing 47% and 32%, respectively. No candidate electromagnetic counterparts were detected by either the GBM or <span class="hlt">LAT</span>. We present a detailed analysis of the GBM and <span class="hlt">LAT</span> data over a range of timescales from seconds to years, using automated pipelines and new techniques for characterizing the <span class="hlt">flux</span> upper bounds across large areas of the sky. Due to the partial GBM and <span class="hlt">LAT</span> coverage of the large LIGO localization regions at the trigger times for both events, differences in source distances and masses, as well as the uncertain degree to which emission from these sources could be beamed, these non-detections cannot be used to constrain the variety of theoretical models recently applied to explain the candidate GBM counterpart to GW150914.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004SPIE.5449..485P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004SPIE.5449..485P"><span>Laser-assisted tympanostomy (<span class="hlt">LAT</span>) in adult individuals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Prokopakis, E. P.; Lachanas, V. A.; Helidonis, Emmanuel S.; Velegrakis, G.</p> <p>2004-06-01</p> <p>Objectives: To assess outcome, in adult individuals undergone Laser Assisted Tympanostomy (<span class="hlt">LAT</span>) without ventilation tube placement. Method: <span class="hlt">LAT</span> was performed on a total of 95 ears (72 individuals). Indications included serous otitis media with effusion (44 ears/31 patients), eustachian tube dysfunction (32 ears/24 patients), acute otitis media (13 ears/11 patients), and endoscopic visualization of the middle ear (6 ears/6 patients). Results: Middle ear disease was resolved after the closure of tympanostomy in 48% of patients with serous otitis media with effusion. In 78% of patients with Eustachian tube dysfunction symptoms were diminished. All patients with acute otitis media had a satisfactory outcome. <span class="hlt">LAT</span> was found quite effective in patients undergoing middle ear endoscopy. Conclusion: <span class="hlt">LAT</span> without ventilation tubes provides a safe alternative surgical option in adult patients in certain cases. The selection criteria for this procedure are addressed in detail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1039276','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1039276"><span><span class="hlt">Lat</span>Mix 2011 and 2012 Dispersion Analysis</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2017-05-15</p> <p>was to complete the analysis and write -up of additional manuscripts relating to <span class="hlt">Lat</span>Mix, and to further strengthen the results for multiple manuscripts...raw waveforms co llected during the <span class="hlt">Lat</span>Mix 20 l I airborne lidar surveys, and completion of the analysis and write -up of major results stemming from...manuscripts published or submitted for publication. 2) Specific Objectives The primary objective of present effort was to complete the analysis and write</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016FrMat...3...33F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016FrMat...3...33F"><span>Advances on Sensitive <span class="hlt">Electron</span>-injection based Cameras for Low-<span class="hlt">Flux</span>, Short-Wave-Infrared Applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fathipour, Vala; Bonakdar, Alireza; Mohseni, Hooman</p> <p>2016-08-01</p> <p>Short-wave infrared (SWIR) photon detection has become an essential technology in the modern world. Sensitive SWIR detector arrays with high pixel density, low noise levels and high signal-to-noise-ratios are highly desirable for a variety of applications including biophotonics, light detection and ranging, optical tomography, and astronomical imaging. As such many efforts in infrared detector research are directed towards improving the performance of the photon detectors operating in this wavelength range. We review the history, principle of operation, present status and possible future developments of a sensitive SWIR detector technology, which has demonstrated to be one of the most promising paths to high pixel density focal plane arrays for low <span class="hlt">flux</span> applications. The so-called <span class="hlt">electron</span>-injection (EI) detector was demonstrated for the first time (in 2007). It offers an overall system-level sensitivity enhancement compared to the p-i-n diode due to a stable internal avalanche-free gain. The amplification method is inherently low noise, and devices exhibit an excess noise of unity. The detector operates in linear-mode and requires only bias voltage of a few volts. The stable detector characteristics, makes formation of high yield large-format, and high pixel density focal plane arrays less challenging compared to other detector technologies such as avalanche photodetectors. Detector is based on the mature InP material system (InP/InAlAs/GaAsSb/InGaAs), and has a cutoff wavelength of 1700 nm. It takes advantage of a unique three-dimensional geometry and combines the efficiency of a large absorbing volume with the sensitivity of a low-dimensional switch (injector) to sense and amplify signals. Current devices provide high-speed response ~ 5 ns rise time, and low jitter ~ 12 ps at room temperature. The internal dark current density is ~ 1 μA/cm2 at room temperature decreasing to 0.1 nA/cm2 at 160 K. EI detectors have been designed, fabricated, and tested during two</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24561586','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24561586"><span>Effect of C-terminal protein tags on pentitol and L-arabinose transport by Ambrosiozyma monospora <span class="hlt">Lat</span>1 and <span class="hlt">Lat</span>2 transporters in Saccharomyces cerevisiae.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Londesborough, John; Richard, Peter; Valkonen, Mari; Viljanen, Kaarina</p> <p>2014-05-01</p> <p>Functional expression in heterologous hosts is often less successful for integral membrane proteins than for soluble proteins. Here, two Ambrosiozyma monospora transporters were successfully expressed in Saccharomyces cerevisiae as tagged proteins. Growth of A. monospora on l-arabinose instead of glucose caused transport activities of l-arabinose, l-arabitol, and ribitol, measured using l-[1-(3)H]arabinose, l-[(14)C]arabitol, and [(14)C]ribitol of demonstrated purity. A. monospora <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 genes were cloned earlier by using their ability to improve the growth of genetically engineered Saccharomyces cerevisiae on l-arabinose. However, the l-arabinose and pentitol transport activities of S. cerevisiae carrying <span class="hlt">LAT</span>1 or <span class="hlt">LAT</span>2 are only slightly greater than those of control strains. S. cerevisiae carrying the <span class="hlt">LAT</span>1 or <span class="hlt">LAT</span>2 gene fused in frame to the genes for green fluorescent protein (GFP) or red fluorescent protein (mCherry) or adenylate kinase (AK) exhibited large (>3-fold for <span class="hlt">LAT</span>1; >20-fold for <span class="hlt">LAT</span>2) increases in transport activities. <span class="hlt">Lat</span>1-mCherry transported l-arabinose with high affinity (Km ≈ 0.03 mM) and l-arabitol and ribitol with very low affinity (Km ≥ 75 mM). The <span class="hlt">Lat</span>2-GFP, <span class="hlt">Lat</span>2-mCherry, and <span class="hlt">Lat</span>2-AK fusion proteins could not transport l-arabinose but were high-affinity pentitol transporters (Kms ≈ 0.2 mM). The l-arabinose and pentitol transport activities of A. monospora could not be completely explained by any combination of the observed properties of tagged <span class="hlt">Lat</span>1 and <span class="hlt">Lat</span>2, suggesting either that tagging and expression in a foreign membrane alters the transport kinetics of <span class="hlt">Lat</span>1 and/or <span class="hlt">Lat</span>2 or that A. monospora contains at least one more l-arabinose transporter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3993308','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3993308"><span>Effect of C-Terminal Protein Tags on Pentitol and l-Arabinose Transport by Ambrosiozyma monospora <span class="hlt">Lat</span>1 and <span class="hlt">Lat</span>2 Transporters in Saccharomyces cerevisiae</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Richard, Peter; Valkonen, Mari; Viljanen, Kaarina</p> <p>2014-01-01</p> <p>Functional expression in heterologous hosts is often less successful for integral membrane proteins than for soluble proteins. Here, two Ambrosiozyma monospora transporters were successfully expressed in Saccharomyces cerevisiae as tagged proteins. Growth of A. monospora on l-arabinose instead of glucose caused transport activities of l-arabinose, l-arabitol, and ribitol, measured using l-[1-3H]arabinose, l-[14C]arabitol, and [14C]ribitol of demonstrated purity. A. monospora <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 genes were cloned earlier by using their ability to improve the growth of genetically engineered Saccharomyces cerevisiae on l-arabinose. However, the l-arabinose and pentitol transport activities of S. cerevisiae carrying <span class="hlt">LAT</span>1 or <span class="hlt">LAT</span>2 are only slightly greater than those of control strains. S. cerevisiae carrying the <span class="hlt">LAT</span>1 or <span class="hlt">LAT</span>2 gene fused in frame to the genes for green fluorescent protein (GFP) or red fluorescent protein (mCherry) or adenylate kinase (AK) exhibited large (>3-fold for <span class="hlt">LAT</span>1; >20-fold for <span class="hlt">LAT</span>2) increases in transport activities. <span class="hlt">Lat</span>1-mCherry transported l-arabinose with high affinity (Km ≈ 0.03 mM) and l-arabitol and ribitol with very low affinity (Km ≥ 75 mM). The <span class="hlt">Lat</span>2-GFP, <span class="hlt">Lat</span>2-mCherry, and <span class="hlt">Lat</span>2-AK fusion proteins could not transport l-arabinose but were high-affinity pentitol transporters (Kms ≈ 0.2 mM). The l-arabinose and pentitol transport activities of A. monospora could not be completely explained by any combination of the observed properties of tagged <span class="hlt">Lat</span>1 and <span class="hlt">Lat</span>2, suggesting either that tagging and expression in a foreign membrane alters the transport kinetics of <span class="hlt">Lat</span>1 and/or <span class="hlt">Lat</span>2 or that A. monospora contains at least one more l-arabinose transporter. PMID:24561586</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1357531','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1357531"><span><I>Fermi</I> -<span class="hlt">Lat</span> Observations Of The Geminga Pulsar</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdo, A. A.</p> <p>2010-08-09</p> <p>We report on the Fermi-<span class="hlt">LAT</span> observations of the Geminga pulsar, the second brightest non-variable GeV source in the γ-ray sky and the first example of a radio-quiet γ-ray pulsar. The observations cover one year, from the launch of the Fermi satellite through 2009 June 15. A data sample of over 60,000 photons enabled us to build a timing solution based solely on γ-rays. Timing analysis shows two prominent peaks, separated by Δphgr = 0.497 ± 0.004 in phase, which narrow with increasing energy. Pulsed γ-rays are observed beyond 18 GeV, precluding emission below 2.7 stellar radii because of magnetic absorption. The phase-averaged spectrum was fitted with a power law with exponential cutoff of spectral index Γ = (1.30 ± 0.01 ± 0.04), cutoff energy E 0 = (2.46 ± 0.04 ± 0.17) GeV, and an integral photon <span class="hlt">flux</span> above 0.1 GeV of (4.14 ± 0.02 ± 0.32) × 10<sup>–6</sup> cm<sup>–2</sup> s<sup>–1</sup>. The first uncertainties are statistical and the second ones are systematic. The phase-resolved spectroscopy shows a clear evolution of the spectral parameters, with the spectral index reaching a minimum value just before the leading peak and the cutoff energy having maxima around the peaks. The phase-resolved spectroscopy reveals that pulsar emission is present at all rotational phases. The spectral shape, broad pulse profile, and maximum photon energy favor the outer magnetospheric emission scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355169-gamma-ray-flaring-activity-from-gravitationally-lensed-blazar-pks-observed-fermi-lat','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355169-gamma-ray-flaring-activity-from-gravitationally-lensed-blazar-pks-observed-fermi-lat"><span>Gamma-ray flaring activity from the gravitationally lensed blazar PKS 1830-211 observed by Fermi <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Abdo, A. A.; Ackermann, M.; Ajello, M.; ...</p> <p>2015-01-23</p> <p>We present that the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope routinely detects the MeV-peaked flat-spectrum radio quasar PKS 1830–211 (z = 2.507). Its apparent isotropic γ-ray luminosity (E > 100 MeV), averaged over ~3 years of observations and peaking on 2010 October 14/15 at 2.9 × 1050 erg s–1, makes it among the brightest high-redshift Fermi blazars. No published model with a single lens can account for all of the observed characteristics of this complex system. Based on radio observations, one expects time-delayed variability to follow about 25 days after a primary flare, with fluxmore » about a factor of 1.5 less. Two large γ-ray flares of PKS 1830–211 have been detected by the <span class="hlt">LAT</span> in the considered period, and no substantial evidence for such a delayed activity was found. This allows us to place a lower limit of about 6 on the γ-ray <span class="hlt">flux</span> ratio between the two lensed images. Swift XRT observations from a dedicated Target of Opportunity program indicate a hard spectrum with no significant correlation of X-ray <span class="hlt">flux</span> with the γ-ray variability. The spectral energy distribution can be modeled with inverse Compton scattering of thermal photons from the dusty torus. The implications of the <span class="hlt">LAT</span> data in terms of variability, the lack of evident delayed flare events, and different radio and γ-ray <span class="hlt">flux</span> ratios are discussed. Lastly, microlensing effects, absorption, size and location of the emitting regions, the complex mass distribution of the system, an energy-dependent inner structure of the source, and <span class="hlt">flux</span> suppression by the lens galaxy for one image path may be considered as hypotheses for understanding our results.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvD..96f3009C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvD..96f3009C"><span>Realistic estimation for the detectability of dark matter subhalos using Fermi-<span class="hlt">LAT</span> catalogs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Calore, Francesca; De Romeri, Valentina; Di Mauro, Mattia; Donato, Fiorenza; Marinacci, Federico</p> <p>2017-09-01</p> <p>Numerical simulations of structure formation have made remarkable progress in recent years, in particular due to the inclusion of baryonic physics evolving with the dark matter component. We generate Monte Carlo realizations of the dark matter subhalo population based on the results of the recent hydrodynamical simulation suite of Milky Way-sized galaxies [F. Marinacci, R. Pakmor, and V. Springel, Mon. Not. R. Astron. Soc. 437, 1750 (2014)., 10.1093/mnras/stt2003]. We then simulate the gamma-ray sky for both the setup of the 3FGL and 2FHL Fermi Large Area Telescope (<span class="hlt">LAT</span>) catalogs, including the contribution from the annihilation of dark matter in the subhalos. We find that the <span class="hlt">flux</span> sensitivity threshold strongly depends on the particle dark matter mass and, more mildly, also on its annihilation channel and the observation latitude. The results differ for the 3FGL and 2FHL catalogs, given their different energy thresholds. We also predict that the number of dark matter subhalos among the unassociated sources is very small. A null number of detectable subhalos in the Fermi-<span class="hlt">LAT</span> 3FGL catalog would imply upper limits on the dark matter annihilation cross section into b b ¯ of 2 ×10-26(5 ×10-25) cm3 /s with MDM=50 (1000 ) GeV . We find less than one extended subhalo in the Fermi-<span class="hlt">LAT</span> 3FGL catalog. As a matter of fact, the differences in the spatial and mass distribution of subhalos between hydrodynamic and dark matter-only runs do not have significant impact on the detectability of dark subhalos in gamma rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19890975','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19890975"><span>Involvement of <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 in the high- and low-affinity transport of L-leucine in human retinal pigment epithelial cells (ARPE-19 cells).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yamamoto, Atsushi; Akanuma, Shin-Ichi; Tachikawa, Masanori; Hosoya, Ken-Ichi</p> <p>2010-05-01</p> <p>System L, which is encoded by <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2, is an amino acid transport system that transports neutral amino acids, including several essential amino acids in an Na+-independent manner. Due to its broad substrate selectivity, system L has been proposed to mediate the transport of amino-acid-related drugs across the blood-tissue barriers. We characterized L-leucine transport and its corresponding transporter in a human retinal pigment epithelial cell line (ARPE-19 cells) as an in vitro model of the outer blood-retinal barrier. [3H]L-leucine uptake by ARPE-19 cells took place in an Na+-, Cl(-)-independent and saturable manner with K(m) values of 8.71 and 220 microM. This process was more potently cis-inhibited by substrates of <span class="hlt">LAT</span>1 than those of <span class="hlt">LAT</span>2. [3H]L-leucine efflux from ARPE-19 cells was trans-stimulated by substrates of <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 through the obligatory exchange mechanism of system L. Although RT-PCR analysis demonstrated that <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 mRNA are expressed in ARPE-19 cells, the <span class="hlt">LAT</span>1 mRNA concentration is 42-fold higher than that of <span class="hlt">LAT</span>2. Moreover, immunoblot analysis demonstrated that <span class="hlt">LAT</span>1 is expressed in ARPE-19 cells. In conclusion, although the transport function of <span class="hlt">LAT</span>1 is greater than that of <span class="hlt">LAT</span>2, <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 are involved in L-leucine transport in ARPE-19 cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PSST...23b5002D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PSST...23b5002D"><span>Time-resolved ion <span class="hlt">flux</span>, <span class="hlt">electron</span> temperature and plasma density measurements in a pulsed Ar plasma using a capacitively coupled planar probe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Darnon, Maxime; Cunge, Gilles; Braithwaite, Nicholas St. J.</p> <p>2014-04-01</p> <p>The resurgence of industrial interest in pulsed radiofrequency plasmas for etching applications highlights the fact that these plasmas are much less well characterized than their continuous wave counterparts. A capacitively coupled planar probe is used to determine the time variations of the ion <span class="hlt">flux</span>, <span class="hlt">electron</span> temperature (of the high-energy tail of the <span class="hlt">electron</span> energy distribution function) and plasma density. For a pulsing frequency of 1 kHz or higher, the plasma never reaches a steady state during the on-time and is not fully extinguished during the off-time. The drop of plasma density during the off-time leads to an overshoot in the <span class="hlt">electron</span> temperature at the beginning of each pulse, particularly at low frequencies, in good agreement with modeling results from the literature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1049754','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1049754"><span>Fermi-<span class="hlt">LAT</span> and Suzaku Observations of the Radio Galaxy Centaurus B</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Katsuta, Junichiro; Tanaka, Y.T.; Stawarz, L.; O'Sullivan, S.P.; Cheung, C.C.; Kataoka, J.; Funk, S.; Yuasa, T.; Odaka, H.; Takahashi, T.; Svoboda, J.; /European Space Agency</p> <p>2012-08-17</p> <p>CentaurusB is a nearby radio galaxy positioned in the Southern hemisphere close to the Galactic plane. Here we present a detailed analysis of about 43 months accumulation of Fermi-<span class="hlt">LAT</span> data and of newly acquired Suzaku X-ray data for Centaurus B. The source is detected at GeV photon energies, although we cannot completely exclude the possibility that it is an artifact due to incorrect modeling of the bright Galactic diffuse emission in the region. The <span class="hlt">LAT</span> image provides a weak hint of a spatial extension of the {gamma} rays along the radio lobes, which is consistent with the lack of source variability in the GeV range. We note that the extension cannot be established statistically due to the low number of the photons. Surprisingly, we do not detect any diffuse emission of the lobes at X-ray frequencies, with the provided upper limit only marginally consistent with the previously claimed ASCA <span class="hlt">flux</span>. The broad-band modeling shows that the observed {gamma}-ray <span class="hlt">flux</span> of the source may be produced within the lobes, if the diffuse non-thermal X-ray emission component is not significantly below the derived Suzaku upper limit. This association would imply that efficient in-situ acceleration of the ultrarelativistic particles is occurring and that the lobes are dominated by the pressure from the relativistic particles. However, if the diffuse X-ray emission is much below the Suzaku upper limits, the observed {gamma}-ray <span class="hlt">flux</span> is not likely to be produced within the lobes, but instead within the unresolved core of Centaurus B. In this case, the extended lobes could be dominated by the pressure of the magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21476102','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21476102"><span>High energy <span class="hlt">electron</span> <span class="hlt">fluxes</span> in dc-augmented capacitively coupled plasmas. II. Effects on twisting in high aspect ratio etching of dielectrics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang Mingmei; Kushner, Mark J.</p> <p>2010-01-15</p> <p>In high aspect ratio (HAR) plasma etching of holes and trenches in dielectrics, sporadic twisting is often observed. Twisting is the randomly occurring divergence of a hole or trench from the vertical. Many causes have been proposed for twisting, one of which is stochastic charging. As feature sizes shrink, the <span class="hlt">fluxes</span> of plasma particles, and ions in particular, into the feature become statistical. Randomly deposited charge by ions on the inside of a feature may be sufficient to produce lateral electric fields which divert incoming ions and initiate nonvertical etching or twisting. This is particularly problematic when etching with fluorocarbon gas mixtures where deposition of polymer in the feature may trap charge. dc-augmented capacitively coupled plasmas (dc-CCPs) have been investigated as a remedy for twisting. In these devices, high energy <span class="hlt">electron</span> (HEE) beams having narrow angular spreads can be generated. HEEs incident onto the wafer which penetrate into HAR features can neutralize the positive charge and so reduce the incidence of twisting. In this paper, we report on results from a computational investigation of plasma etching of SiO{sub 2} in a dc-CCP using Ar/C{sub 4}F{sub 8}/O{sub 2} gas mixtures. We found that HEE beams incident onto the wafer are capable of penetrating into features and partially neutralizing positive charge buildup due to sporadic ion charging, thereby reducing the incidence of twisting. Increasing the rf bias power increases the HEE beam energy and <span class="hlt">flux</span> with some indication of improvement of twisting, but there are also changes in the ion energy and <span class="hlt">fluxes</span>, so this is not an unambiguous improvement. Increasing the dc bias voltage while keeping the rf bias voltage constant increases the maximum energy of the HEE and its <span class="hlt">flux</span> while the ion characteristics remain nearly constant. For these conditions, the occurrence of twisting decreases with increasing HEE energy and <span class="hlt">flux</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/97156','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/97156"><span>Multi-satellite characterization of the large energetic <span class="hlt">electron</span> <span class="hlt">flux</span> increase at L = 4-7, in the five-day period following the March 24, 1991, solar energetic particle event</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ingraham, J.C.; Cayton, T.E.; Belian, R.D.</p> <p>1994-12-31</p> <p>Following the giant magnetic storm that started on March 24, 1991, and the immediately-preceding solar energetic particle (SEP) event, a dramatic increase in the <span class="hlt">flux</span> of energetic <span class="hlt">electrons</span> was observed to occur on several satellites (using Los Alamos instruments aboard two geosynchronous satellites and two GPS satellites, plus energetic <span class="hlt">electron</span> data from the CRRES satellite) sampling the L=4-7 region of the magnetosphere. We find that: this <span class="hlt">flux</span> buildup at the larger L-values (L--6-7) first appears near the magnetic equator and subsequently spreads to higher magnetic latitudes; the <span class="hlt">flux</span> buildup near the magnetic equator peaks first at the higher L before it peaks at the lower L; analysis of the angular distribution of energetic <span class="hlt">electrons</span> at geosynchronous orbit shows that the <span class="hlt">flux</span> buildup begins first with the buildup of energetic <span class="hlt">electrons</span> (>300 keV) moving perpendicular to the magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/451682','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/451682"><span>Multi-satellite characterization of the large energetic <span class="hlt">electron</span> <span class="hlt">flux</span> increase at {ital L}=4{endash}7, in the five-day period following the March 24, 1991, solar energetic particle event</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ingraham, J.C.; Cayton, T.E.; Belian, R.D.; Christensen, R.A.; Guyker, F.; Meier, M.M.; Reeves, G.D.; Brautigam, D.H.; Gussenhoven, M.S.; Robinson, R.M.</p> <p>1996-07-01</p> <p>Following the giant magnetic storm that started on March 24, 1991, and the immediately-preceding solar energetic particle (SEP) event, a dramatic increase in the <span class="hlt">flux</span> of energetic <span class="hlt">electrons</span> was observed to occur on several satellites (using Los Alamos instruments aboard two geosynchronous satellites and two GPS satellites, plus energetic <span class="hlt">electron</span> data from the CRRES satellite) sampling the {ital L}=4{endash}7 region of the magnetosphere. We find that this <span class="hlt">flux</span> buildup at the larger {ital L}-values ({ital L}=6{endash}7) first appears near the magnetic equator and subsequently spreads to higher magnetic latitudes; the <span class="hlt">flux</span> buildup near the magnetic equator peaks first at the higher {ital L} before it peaks at the lower {ital L} analysis of the angular distribution of energetic <span class="hlt">electrons</span> at geosynchronous orbit shows that the <span class="hlt">flux</span> buildup begins first with the buildup of energetic <span class="hlt">electrons</span> ({gt}300 keV) moving perpendicular to the magnetic field. {copyright} {ital 1996 American Institute of Physics.}</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JAP....92.4935O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JAP....92.4935O"><span>Diagnostics and two-dimensional simulation of low-frequency inductively coupled plasmas with neutral gas heating and <span class="hlt">electron</span> heat <span class="hlt">fluxes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ostrikov, K. N.; Denysenko, I. B.; Tsakadze, E. L.; Xu, S.; Storer, R. G.</p> <p>2002-11-01</p> <p>This article presents the results on the diagnostics and numerical modeling of low-frequency (approx460 KHz) inductively coupled plasmas generated in a cylindrical metal chamber by an external flat spiral coil. Experimental data on the <span class="hlt">electron</span> number densities and temperatures, <span class="hlt">electron</span> energy distribution functions, and optical emission intensities of the abundant plasma species in low/intermediate pressure argon discharges are included. The spatial profiles of the plasma density, <span class="hlt">electron</span> temperature, and excited argon species are computed, for different rf powers and working gas pressures, using the two-dimensional fluid approach. The model allows one to achieve a reasonable agreement between the computed and experimental data. The effect of the neutral gas temperature on the plasma parameters is also investigated. It is shown that neutral gas heating (at rf powers[greater-than-or-equal, slanted]0.55 kW) is one of the key factors that control the <span class="hlt">electron</span> number density and temperature. The dependence of the average rf power loss, per <span class="hlt">electron</span>-ion pair created, on the working gas pressure shows that the <span class="hlt">electron</span> heat <span class="hlt">flux</span> to the walls appears to be a critical factor in the total power loss in the discharge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25580517','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25580517"><span>Boronophenylalanine, a boron delivery agent for boron neutron capture therapy, is transported by ATB0,+, <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wongthai, Printip; Hagiwara, Kohei; Miyoshi, Yurika; Wiriyasermkul, Pattama; Wei, Ling; Ohgaki, Ryuichi; Kato, Itsuro; Hamase, Kenji; Nagamori, Shushi; Kanai, Yoshikatsu</p> <p>2015-03-01</p> <p>The efficacy of boron neutron capture therapy relies on the selective delivery of boron carriers to malignant cells. p-Boronophenylalanine (BPA), a boron delivery agent, has been proposed to be localized to cells through transporter-mediated mechanisms. In this study, we screened aromatic amino acid transporters to identify BPA transporters. Human aromatic amino acid transporters were functionally expressed in Xenopus oocytes and examined for BPA uptake and kinetic parameters. The roles of the transporters in BPA uptake were characterized in cancer cell lines. For the quantitative assessment of BPA uptake, HPLC was used throughout the study. Among aromatic amino acid transporters, ATB(0,+), <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 were found to transport BPA with Km values of 137.4 ± 11.7, 20.3 ± 0.8 and 88.3 ± 5.6 μM, respectively. Uptake experiments in cancer cell lines revealed that the <span class="hlt">LAT</span>1 protein amount was the major determinant of BPA uptake at 100 μM, whereas the contribution of ATB(0,+) became significant at 1000 μM, accounting for 20-25% of the total BPA uptake in MCF-7 breast cancer cells. ATB(0,+), <span class="hlt">LAT</span>1 and <span class="hlt">LAT</span>2 transport BPA at affinities comparable with their endogenous substrates, suggesting that they could mediate effective BPA uptake in vivo. The high and low affinities of <span class="hlt">LAT</span>1 and ATB(0,+), respectively, differentiate their roles in BPA uptake. ATB(0,+), as well as <span class="hlt">LAT</span>1, could contribute significantly to the tumor accumulation of BPA at clinical dose.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4344199','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4344199"><span><span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 Phosphorylate CDC26 to Modulate Assembly of the Tetratricopeptide Repeat Subcomplex of APC/C</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Masuda, Kenta; Chiyoda, Tatsuyuki; Sugiyama, Naoyuki; Segura-Cabrera, Aldo; Kabe, Yasuaki; Ueki, Arisa; Banno, Koji; Suematsu, Makoto; Aoki, Daisuke; Ishihama, Yasushi; Saya, Hideyuki; Kuninaka, Shinji</p> <p>2015-01-01</p> <p>In budding yeast, the Mitotic Exit Network (MEN) regulates anaphase promoting complex/cyclosome (APC/C) via the Dbf2-Cdc14 signaling cascade. Dbf2 kinase phosphorylates and activates Cdc14 phosphatase, which removes the inhibitory phosphorylation of the APC/C cofactor Cdh1. Although each component of the MEN was highly conserved during evolution, there is presently no evidence supporting direct phosphorylation of CDC14 by large tumor suppressor kinase 1 (<span class="hlt">LATS</span>1), the human counterpart of Dbf2; hence, it is unclear how <span class="hlt">LATS</span>1 regulates APC/C. Here, we demonstrate that <span class="hlt">LATS</span>1 phosphorylates the Thr7 (T7) residue of the APC/C component CDC26 directly. Nocodazole-induced phosphorylation of T7 was reduced by knockdown of <span class="hlt">LATS</span>1 and <span class="hlt">LATS</span>2 in HeLa cells, indicating that both of these kinases contribute to the phosphorylation of CDC26 in vivo. The T7 residue of CDC26 is critical for its interaction with APC6, a tetratricopeptide repeat-containing subunit of APC/C, and mutation of this residue to Asp (T7D) reduced the interaction of CDC26 with APC6. Replacement of endogenous CDC26 in HeLa cells with exogenous phosphor-mimic T7D-mutated CDC26 increased the elution size of APC/C subunits in a gel filtration assay, implying a change in the APC/C assembly upon phosphorylation of CDC26. Furthermore, T7D-mutated CDC26 promoted the ubiquitination of polo-like kinase 1, a well-known substrate of APC/C. Overall, these results suggest that <span class="hlt">LATS</span>1/2 are novel kinases involved in APC/C phosphorylation and indicate a direct regulatory link between <span class="hlt">LATS</span>1/2 and APC/C. PMID:25723520</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1355715','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1355715"><span>Search for gamma-ray emission from AE Aquarii with seven year of Fermi <span class="hlt">LAT</span> observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, Jian; Torres, Diego F.; Rea, Nanda; Wilhelmi, Emma de Ona; Papitto, Alessandro; Hou, Xian; Mauche, Christopher W.</p> <p>2016-11-14</p> <p>AE Aquarii (AE Aqr) is a cataclysmic binary hosting one of the fastest rotating (${P}_{\\mathrm{spin}}$ = 33.08 s) white dwarfs (WDs) known. Based on seven years of Fermi Large Area Telescope (<span class="hlt">LAT</span>) Pass 8 data, we report on a deep search for gamma-ray emission from AE Aqr. When using X-ray observations from ASCA, XMM-Newton, Chandra, Swift, Suzaku, and NuSTAR, spanning 20 years, we substantially extend and improve the spin ephemeris of AE Aqr. Using this ephemeris, we searched for gamma-ray pulsations at the spin period of the WD. We detected no gamma-ray pulsations above 3σ significance. Neither phase-averaged gamma-ray emission nor gamma-ray variability of AE Aqr is detected by Fermi <span class="hlt">LAT</span>. We also impose the most restrictive upper limit to the gamma-ray <span class="hlt">flux</span> from AE Aqr to date: $1.3\\times {10}^{-12}$ erg cm<sup>-2</sup> s<sup>-1</sup> in the 100 MeV–300 GeV energy range, providing constraints on models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22089855','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22089855"><span>POLARIZATION AND VARIATION OF NEAR-INFRARED LIGHT FROM FERMI/<span class="hlt">LAT</span> {gamma}-RAY SOURCES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fujiwara, M.; Matsuoka, Y.; Ienaka, N.</p> <p>2012-10-01</p> <p>We present the results of our follow-up observation program of {gamma}-ray sources detected by the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-ray Space Telescope. Twenty-six blazars and thirty-nine sources unidentified at other wavelengths were targeted at the Infrared Survey Facility 1.4 m telescope equipped with the SIRIUS/SIRPOL imager and polarimeter. H-band magnitudes of the blazars at the epoch of 2010 December-2011 February are presented, which reveal clear <span class="hlt">flux</span> variation since the Two Micron All Sky Survey observations and can be useful data for variation analyses of these objects in longer periods. We also find that nearly half of the {gamma}-ray blazars are highly (>10%) polarized in near-infrared wavelengths. Combining the polarization and variation properties, most ({approx}90%) of the blazars are clearly distinguished from all other types of objects at high Galactic latitudes. On the other hand, we find only one highly polarized and/or variable object in the fields of unidentified sources. This object is a counterpart of the optical variable source PQV1 J131553.00-073302.0 and the radio source NVSS J131552-073301 and is a promising candidate of new {gamma}-ray blazars. From the measured polarization and variation statistics, we conclude that most of the Fermi/<span class="hlt">LAT</span> unidentified sources are not likely similar types of objects to the known {gamma}-ray blazars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355715-search-gamma-ray-emission-from-ae-aquarii-seven-year-fermi-lat-observations','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355715-search-gamma-ray-emission-from-ae-aquarii-seven-year-fermi-lat-observations"><span>Search for gamma-ray emission from AE Aquarii with seven year of Fermi <span class="hlt">LAT</span> observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Li, Jian; Torres, Diego F.; Rea, Nanda; ...</p> <p>2016-11-14</p> <p>AE Aquarii (AE Aqr) is a cataclysmic binary hosting one of the fastest rotating (more » $${P}_{\\mathrm{spin}}$$ = 33.08 s) white dwarfs (WDs) known. Based on seven years of Fermi Large Area Telescope (<span class="hlt">LAT</span>) Pass 8 data, we report on a deep search for gamma-ray emission from AE Aqr. When using X-ray observations from ASCA, XMM-Newton, Chandra, Swift, Suzaku, and NuSTAR, spanning 20 years, we substantially extend and improve the spin ephemeris of AE Aqr. Using this ephemeris, we searched for gamma-ray pulsations at the spin period of the WD. We detected no gamma-ray pulsations above 3σ significance. Neither phase-averaged gamma-ray emission nor gamma-ray variability of AE Aqr is detected by Fermi <span class="hlt">LAT</span>. We also impose the most restrictive upper limit to the gamma-ray <span class="hlt">flux</span> from AE Aqr to date: $$1.3\\times {10}^{-12}$$ erg cm-2 s-1 in the 100 MeV–300 GeV energy range, providing constraints on models.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22521478','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22521478"><span>FERMI-<span class="hlt">LAT</span> OBSERVATIONS OF HIGH-ENERGY γ-RAY EMISSION TOWARD THE GALACTIC CENTER</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ajello, M.; Albert, A.; Blandford, R. D.; Bloom, E. D.; Bottacini, E.; Caliandro, G. A.; Cameron, R. A.; Atwood, W. B.; Caputo, R.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bechtol, K.; Bellazzini, R.; Bissaldi, E.; Bonino, R.; Brandt, T. J.; Bregeon, J.; and others</p> <p>2016-03-01</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has provided the most detailed view to date of the emission toward the Galactic center (GC) in high-energy γ-rays. This paper describes the analysis of data taken during the first 62 months of the mission in the energy range 1–100 GeV from a 15° × 15° region about the direction of the GC. Specialized interstellar emission models (IEMs) are constructed to enable the separation of the γ-ray emissions produced by cosmic ray particles interacting with the interstellar gas and radiation fields in the Milky Way into that from the inner ∼1 kpc surrounding the GC, and that from the rest of the Galaxy. A catalog of point sources for the 15° × 15° region is self-consistently constructed using these IEMs: the First Fermi-<span class="hlt">LAT</span> Inner Galaxy Point Source Catalog (1FIG). The spatial locations, <span class="hlt">fluxes</span>, and spectral properties of the 1FIG sources are presented, and compared with γ-ray point sources over the same region taken from existing catalogs. After subtracting the interstellar emission and point-source contributions a residual is found. If templates that peak toward the GC are used to model the positive residual the agreement with the data improves, but none of the additional templates tried account for all of its spatial structure. The spectrum of the positive residual modeled with these templates has a strong dependence on the choice of IEM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2254472B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2254472B"><span>The First Fermi-<span class="hlt">LAT</span> SNR Catalog: GeV Characteristics and Cosmic Ray Implications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brandt, T. J.; Acero, F.; de Palma, F.; Hewitt, J.; Renaud, M.; Fermi-LAT Collaboration</p> <p>2015-08-01</p> <p>Galactic cosmic rays (CR) sources, classically proposed to be Supernova Remnants (SNRs), must meet the energetic particle content required by direct measurements of high energy CRs. Indirect gamma-ray measurements of SNRs with the Fermi Large Area Telescope (<span class="hlt">LAT</span>) have now shown directly that at least three SNRs accelerate protons. With the first Fermi <span class="hlt">LAT</span> SNR Catalog, we have systematically characterized the GeV gamma-rays emitted by 279 SNRs known primarily from radio surveys. We present these sources in a multiwavelength context, including studies of correlations between GeV and radio size, <span class="hlt">flux</span>, and index, TeV index, and age and environment tracers, in order to better understand effects of evolution and environment on the GeV emission. We show that previously sufficient models of SNRs' GeV emission no longer adequately describe the data. To address the question of CR origins, we also examine the SNRs' maximal CR contribution assuming the GeV emission arises solely from proton interactions. Improved breadth and quality of multiwavelength data, including distances and local densities, and more, higher resolution gamma-ray data with correspondingly improved Galactic diffuse models will strengthen this constraint.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.463.1068R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.463.1068R"><span>Search for gamma-ray emission from star-forming galaxies with Fermi <span class="hlt">LAT</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rojas-Bravo, César; Araya, Miguel</p> <p>2016-11-01</p> <p>Recent studies have found a positive correlation between the star formation rate (SFR) of galaxies and their gamma-ray luminosity. Galaxies with a high SFR are expected to produce a large amount of high-energy cosmic rays, which emit gamma-rays when interacting with the interstellar medium and radiation fields. We search for gamma-ray emission from a sample of galaxies within and beyond the Local Group with data from the <span class="hlt">LAT</span> instrument onboard the Fermi satellite. We exclude recently detected galaxies (NGC 253, M82, NGC 4945, NGC 1068, NGC 2146, Arp 220) and use seven years of cumulative `Pass 8' data from the <span class="hlt">LAT</span> in the 100 MeV to 100 GeV range. No new detections are seen in the data and upper limits for the gamma-ray <span class="hlt">fluxes</span> are calculated. The correlation between gamma-ray luminosity and infrared luminosity for galaxies obtained using our new upper limits is in agreement with a previously published correlation, but the new upper limits imply that some galaxies are not as efficient gamma-ray emitters as previously thought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...819...44A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...819...44A"><span>Fermi-<span class="hlt">LAT</span> Observations of High-Energy Gamma-Ray Emission toward the Galactic Center</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ajello, M.; Albert, A.; Atwood, W. B.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Brandt, T. J.; Bregeon, J.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caputo, R.; Caragiulo, M.; Caraveo, P. A.; Cecchi, C.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Cohen-Tanugi, J.; Cominsky, L. R.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Desiante, R.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Ferrara, E. C.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Gomez-Vargas, G. A.; Grenier, I. A.; Guiriec, S.; Gustafsson, M.; Harding, A. K.; Hewitt, J. W.; Hill, A. B.; Horan, D.; Jogler, T.; Jóhannesson, G.; Johnson, A. S.; Kamae, T.; Karwin, C.; Knödlseder, J.; Kuss, M.; Larsson, S.; Latronico, L.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Magill, J.; Maldera, S.; Malyshev, D.; Manfreda, A.; Mayer, M.; Mazziotta, M. N.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Moiseev, A. A.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nuss, E.; Ohno, M.; Ohsugi, T.; Omodei, N.; Orlando, E.; Ormes, J. F.; Paneque, D.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Ritz, S.; Sánchez-Conde, M.; Saz Parkinson, P. M.; Sgrò, C.; Siskind, E. J.; Smith, D. A.; Spada, F.; Spandre, G.; Spinelli, P.; Suson, D. J.; Tajima, H.; Takahashi, H.; Thayer, J. B.; Torres, D. F.; Tosti, G.; Troja, E.; Uchiyama, Y.; Vianello, G.; Winer, B. L.; Wood, K. S.; Zaharijas, G.; Zimmer, S.</p> <p>2016-03-01</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has provided the most detailed view to date of the emission toward the Galactic center (GC) in high-energy γ-rays. This paper describes the analysis of data taken during the first 62 months of the mission in the energy range 1-100 GeV from a 15° × 15° region about the direction of the GC. Specialized interstellar emission models (IEMs) are constructed to enable the separation of the γ-ray emissions produced by cosmic ray particles interacting with the interstellar gas and radiation fields in the Milky Way into that from the inner ˜1 kpc surrounding the GC, and that from the rest of the Galaxy. A catalog of point sources for the 15° × 15° region is self-consistently constructed using these IEMs: the First Fermi-<span class="hlt">LAT</span> Inner Galaxy Point Source Catalog (1FIG). The spatial locations, <span class="hlt">fluxes</span>, and spectral properties of the 1FIG sources are presented, and compared with γ-ray point sources over the same region taken from existing catalogs. After subtracting the interstellar emission and point-source contributions a residual is found. If templates that peak toward the GC are used to model the positive residual the agreement with the data improves, but none of the additional templates tried account for all of its spatial structure. The spectrum of the positive residual modeled with these templates has a strong dependence on the choice of IEM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170003550&hterms=Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DEnergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170003550&hterms=Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DEnergy"><span>Fermi-<span class="hlt">Lat</span> Observations of High-Energy Gamma-Ray Emission Toward the Galactic Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ajello, M.; Albert, A.; Atwood, W.B.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Brandt, T. J.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170003550'); toggleEditAbsImage('author_20170003550_show'); toggleEditAbsImage('author_20170003550_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170003550_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170003550_hide"></p> <p>2016-01-01</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has provided the most detailed view to date of the emission toward the Galactic center (GC) in high-energy gamma-rays. This paper describes the analysis of data taken during the first 62 months of the mission in the energy range 1-100 GeV from a 15 degrees x 15 degrees region about the direction of the GC. Specialized interstellar emission models (IEMs) are constructed to enable the separation of the gamma-ray emissions produced by cosmic ray particles interacting with the interstellar gas and radiation fields in the Milky Way into that from the inner 1 kpc surrounding the GC, and that from the rest of the Galaxy. A catalog of point sources for the 15 degrees x 15 degrees region is self-consistently constructed using these IEMs: the First Fermi-<span class="hlt">LAT</span> Inner Galaxy Point SourceCatalog (1FIG). The spatial locations, <span class="hlt">fluxes</span>, and spectral properties of the 1FIG sources are presented, and compared with gamma-ray point sources over the same region taken from existing catalogs. After subtracting the interstellar emission and point-source contributions a residual is found. If templates that peak toward the GC areused to model the positive residual the agreement with the data improves, but none of the additional templates tried account for all of its spatial structure. The spectrum of the positive residual modeled with these templates has a strong dependence on the choice of IEM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160005794&hterms=fisica+general&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dfisica%2Bgeneral','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160005794&hterms=fisica+general&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dfisica%2Bgeneral"><span>The First FERMI-<span class="hlt">LAT</span> Gamma-Ray Burst Catalog</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ackermann, M.; Ajello, M.; Asano, K.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20160005794'); toggleEditAbsImage('author_20160005794_show'); toggleEditAbsImage('author_20160005794_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20160005794_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20160005794_hide"></p> <p>2013-01-01</p> <p>In three years of observations since the beginning of nominal science operations in 2008 August, the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-Ray Space Telescope has observed high-energy great than (20 MeV) gamma-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 GRBs above approximately 20 MeV. The first Fermi-<span class="hlt">LAT</span> catalog of GRBs is a compilation of these detections and provides a systematic study of high-energy emission from GRBs for the first time. To generate the catalog, we examined 733 GRBs detected by the Gamma-Ray Burst Monitor (GBM) on Fermi and processed each of them using the same analysis sequence. Details of the methodology followed by the <span class="hlt">LAT</span> collaboration for the GRB analysis are provided. We summarize the temporal and spectral properties of the <span class="hlt">LAT</span>-detected GRBs. We also discuss characteristics of <span class="hlt">LAT</span>-detected emission such as its delayed onset and longer duration compared with emission detected by the GBM, its power-law temporal decay at late times, and the fact that it is dominated by a power-law spectral component that appears in addition to the usual Band model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170004000&hterms=Fisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DFisica','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170004000&hterms=Fisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DFisica"><span>Fermi-<span class="hlt">LAT</span> Observations of the LIGO Event GW150914</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ackermann, M.; Ajello, M.; Albert, A.; Anderson, B.; Arimoto, M.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170004000'); toggleEditAbsImage('author_20170004000_show'); toggleEditAbsImage('author_20170004000_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170004000_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170004000_hide"></p> <p>2016-01-01</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has an instantaneous field of view (FoV) covering 1 5 of the sky and it completes a survey of the entire sky in high-energy gamma-rays every 3 hr. It enables searches for transient phenomena over timescales from milliseconds to years. Among these phenomena could be electromagnetic counterparts to gravitational wave (GW) sources. In this paper, we present a detailed study of the <span class="hlt">LAT</span> observations relevant to Laser Interferometer Gravitational-wave Observatory (LIGO) event GW150914, which is the first direct detection of gravitational waves and has been interpreted as being due to the coalescence of two stellar-mass black holes. The localization region for GW150914 was outside the <span class="hlt">LAT</span> FoV at the time of the GW signal. However, as part of routine survey observations, the <span class="hlt">LAT</span> observed the entire LIGO localization region within approx. 70 minutes of the trigger and thus enabled a comprehensive search for a gamma-ray counterpart to GW150914.The study of the <span class="hlt">LAT</span> data presented here did not find any potential counterparts to GW150914, but it did provide limits on the presence of a transient counterpart above 100 MeV on timescales of hours to days over the entire GW150914 localization region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...823L...2A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...823L...2A"><span>Fermi-<span class="hlt">LAT</span> Observations of the LIGO Event GW150914</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ackermann, M.; Ajello, M.; Albert, A.; Anderson, B.; Arimoto, M.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Baring, M. G.; Bastieri, D.; Becerra Gonzalez, J.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Brandt, T. J.; Bregeon, J.; Britto, R. J.; Bruel, P.; Buehler, R.; Burnett, T. H.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caputo, R.; Caragiulo, M.; Caraveo, P. A.; Casandjian, J. M.; Cavazzuti, E.; Charles, E.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Cohen-Tanugi, J.; Cominsky, L. R.; Condon, B.; Costanza, F.; Cuoco, A.; Cutini, S.; D'Ammando, F.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Domínguez, A.; Drell, P. S.; Dubois, R.; Dumora, D.; Favuzzi, C.; Fegan, S. J.; Ferrara, E. C.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Giglietto, N.; Giomi, M.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Gomez-Vargas, G. A.; Granot, J.; Green, D.; Grenier, I. A.; Grondin, M.-H.; Grove, J. E.; Guillemot, L.; Guiriec, S.; Hadasch, D.; Harding, A. K.; Hays, E.; Hewitt, J. W.; Hill, A. B.; Horan, D.; Jogler, T.; Jóhannesson, G.; Kamae, T.; Kensei, S.; Kocevski, D.; Kuss, M.; La Mura, G.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Madejski, G. M.; Magill, J.; Maldera, S.; Manfreda, A.; Marelli, M.; Mayer, M.; Mazziotta, M. N.; McEnery, J. E.; Meyer, M.; Michelson, P. F.; Mirabal, N.; Mizuno, T.; Moiseev, A. A.; Monzani, M. E.; Moretti, E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Negro, M.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Racusin, J. L.; Rainò, S.; Rando, R.; Razzaque, S.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; Rochester, L. S.; Romani, R. W.; Saz Parkinson, P. M.; Sgrò, C.; Simone, D.; Siskind, E. J.; Smith, D. A.; Spada, F.; Spandre, G.; Spinelli, P.; Suson, D. J.; Tajima, H.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Torres, D. F.; Troja, E.; Uchiyama, Y.; Venters, T. M.; Vianello, G.; Wood, K. S.; Wood, M.; Zaharijas, G.; Zhu, S.; Zimmer, S.</p> <p>2016-05-01</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has an instantaneous field of view (FoV) covering ˜ 1/5 of the sky and it completes a survey of the entire sky in high-energy gamma-rays every 3 hr. It enables searches for transient phenomena over timescales from milliseconds to years. Among these phenomena could be electromagnetic counterparts to gravitational wave (GW) sources. In this paper, we present a detailed study of the <span class="hlt">LAT</span> observations relevant to Laser Interferometer Gravitational-wave Observatory (LIGO) event GW150914, which is the first direct detection of gravitational waves and has been interpreted as being due to the coalescence of two stellar-mass black holes. The localization region for GW150914 was outside the <span class="hlt">LAT</span> FoV at the time of the GW signal. However, as part of routine survey observations, the <span class="hlt">LAT</span> observed the entire LIGO localization region within ˜70 minutes of the trigger and thus enabled a comprehensive search for a γ-ray counterpart to GW150914. The study of the <span class="hlt">LAT</span> data presented here did not find any potential counterparts to GW150914, but it did provide limits on the presence of a transient counterpart above 100 MeV on timescales of hours to days over the entire GW150914 localization region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1356559-first-fermi-lat-gamma-ray-burst-catalog','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1356559-first-fermi-lat-gamma-ray-burst-catalog"><span>The first Fermi-<span class="hlt">LAT</span> Gamma-Ray burst catalog</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ackermann, M.; Ajello, M.; Asano, K.; ...</p> <p>2013-10-23</p> <p>In three years of observations since the beginning of nominal science operations in 2008 August, the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-Ray Space Telescope has observed high-energy (gsim 20 MeV) γ-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 GRBs above ~20 MeV. The first Fermi-<span class="hlt">LAT</span> catalog of GRBs is a compilation of these detections and provides a systematic study of high-energy emission from GRBs for the first time. To generate the catalog, we examined 733 GRBs detected by the Gamma-Ray Burst Monitor (GBM) on Fermi andmore » processed each of them using the same analysis sequence. Details of the methodology followed by the <span class="hlt">LAT</span> collaboration for the GRB analysis are provided. Here, we summarize the temporal and spectral properties of the <span class="hlt">LAT</span>-detected GRBs. We also discuss characteristics of <span class="hlt">LAT</span>-detected emission such as its delayed onset and longer duration compared with emission detected by the GBM, its power-law temporal decay at late times, and the fact that it is dominated by a power-law spectral component that appears in addition to the usual Band model.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355694-fermi-lat-observations-ligo-event-gw150914','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355694-fermi-lat-observations-ligo-event-gw150914"><span>Fermi-<span class="hlt">LAT</span> Observations of the LIGO Event GW150914</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ackermann, M.; Ajello, M.; Albert, A.; ...</p> <p>2016-05-12</p> <p>The Fermi Large Area Telescope (<span class="hlt">LAT</span>) has an instantaneous field of view (FoV) covering ~1/5 of the sky and it completes a survey of the entire sky in high-energy gamma-rays every 3 hr. It enables searches for transient phenomena over timescales from milliseconds to years. Among these phenomena could be electromagnetic counterparts to gravitational wave (GW) sources. In this study, we present a detailed study of the <span class="hlt">LAT</span> observations relevant to Laser Interferometer Gravitational-wave Observatory (LIGO) event GW150914, which is the first direct detection of gravitational waves and has been interpreted as being due to the coalescence of two stellar-massmore » black holes. The localization region for GW150914 was outside the <span class="hlt">LAT</span> FoV at the time of the GW signal. However, as part of routine survey observations, the <span class="hlt">LAT</span> observed the entire LIGO localization region within ~70 minutes of the trigger and thus enabled a comprehensive search for a γ-ray counterpart to GW150914. Finally, the study of the <span class="hlt">LAT</span> data presented here did not find any potential counterparts to GW150914, but it did provide limits on the presence of a transient counterpart above 100 MeV on timescales of hours to days over the entire GW150914 localization region.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160005794&hterms=Fisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DFisica','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160005794&hterms=Fisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DFisica"><span>The First FERMI-<span class="hlt">LAT</span> Gamma-Ray Burst Catalog</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ackermann, M.; Ajello, M.; Asano, K.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Bhat, P. N.; Bissaldi, E.; Bloom, E. D.; Bonamente, E.; Bonnell, J.; Bouvier, A.; Brandt, T. J.; Bregeon, J.; Brigida, M.; Bruel, P.; Burgess, J. Michael; Buson, S.; Byrne, D.; Caliandro, G. A.; Ferrara, E. C.; Gehrels, N.; Guiriec, S.; McEnery, J. E.; Nemmen, R.; Perkins, J. S.; Racusin, J. L.; Thompson, D. J.; Kouveliotou, C.</p> <p>2013-01-01</p> <p>In three years of observations since the beginning of nominal science operations in 2008 August, the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-Ray Space Telescope has observed high-energy great than (20 MeV) gamma-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 GRBs above approximately 20 MeV. The first Fermi-<span class="hlt">LAT</span> catalog of GRBs is a compilation of these detections and provides a systematic study of high-energy emission from GRBs for the first time. To generate the catalog, we examined 733 GRBs detected by the Gamma-Ray Burst Monitor (GBM) on Fermi and processed each of them using the same analysis sequence. Details of the methodology followed by the <span class="hlt">LAT</span> collaboration for the GRB analysis are provided. We summarize the temporal and spectral properties of the <span class="hlt">LAT</span>-detected GRBs. We also discuss characteristics of <span class="hlt">LAT</span>-detected emission such as its delayed onset and longer duration compared with emission detected by the GBM, its power-law temporal decay at late times, and the fact that it is dominated by a power-law spectral component that appears in addition to the usual Band model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22273269','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22273269"><span>THE FIRST FERMI-<span class="hlt">LAT</span> GAMMA-RAY BURST CATALOG</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ackermann, M.; Ajello, M.; Asano, K.; Axelsson, M.; Baldini, L.; Ballet, J.; Bastieri, D.; Bechtol, K.; Bloom, E. D.; Bellazzini, R.; Bregeon, J.; Bhat, P. N.; Bissaldi, E.; Bonamente, E.; Bonnell, J.; Brandt, T. J.; Bouvier, A. E-mail: giacomov@slac.stanford.edu; and others</p> <p>2013-11-01</p> <p>In three years of observations since the beginning of nominal science operations in 2008 August, the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-Ray Space Telescope has observed high-energy (∼> 20 MeV) γ-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 GRBs above ∼20 MeV. The first Fermi-<span class="hlt">LAT</span> catalog of GRBs is a compilation of these detections and provides a systematic study of high-energy emission from GRBs for the first time. To generate the catalog, we examined 733 GRBs detected by the Gamma-Ray Burst Monitor (GBM) on Fermi and processed each of them using the same analysis sequence. Details of the methodology followed by the <span class="hlt">LAT</span> collaboration for the GRB analysis are provided. We summarize the temporal and spectral properties of the <span class="hlt">LAT</span>-detected GRBs. We also discuss characteristics of <span class="hlt">LAT</span>-detected emission such as its delayed onset and longer duration compared with emission detected by the GBM, its power-law temporal decay at late times, and the fact that it is dominated by a power-law spectral component that appears in addition to the usual Band model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ApJS..209...11A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ApJS..209...11A"><span>The First Fermi-<span class="hlt">LAT</span> Gamma-Ray Burst Catalog</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ackermann, M.; Ajello, M.; Asano, K.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Bhat, P. N.; Bissaldi, E.; Bloom, E. D.; Bonamente, E.; Bonnell, J.; Bouvier, A.; Brandt, T. J.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Burgess, J. Michael; Buson, S.; Byrne, D.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cecchi, C.; Charles, E.; Chaves, R. C. G.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Connaughton, V.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Dermer, C. D.; Desiante, R.; Digel, S. W.; Dingus, B. L.; Di Venere, L.; Drell, P. S.; Drlica-Wagner, A.; Dubois, R.; Favuzzi, C.; Ferrara, E. C.; Fitzpatrick, G.; Foley, S.; Franckowiak, A.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Goldstein, A.; Granot, J.; Grenier, I. A.; Grove, J. E.; Gruber, D.; Guiriec, S.; Hadasch, D.; Hanabata, Y.; Hayashida, M.; Horan, D.; Hou, X.; Hughes, R. E.; Inoue, Y.; Jackson, M. S.; Jogler, T.; Jóhannesson, G.; Johnson, A. S.; Johnson, W. N.; Kamae, T.; Kataoka, J.; Kawano, T.; Kippen, R. M.; Knödlseder, J.; Kocevski, D.; Kouveliotou, C.; Kuss, M.; Lande, J.; Larsson, S.; Latronico, L.; Lee, S.-H.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Massaro, F.; Mayer, M.; Mazziotta, M. N.; McBreen, S.; McEnery, J. E.; McGlynn, S.; Michelson, P. F.; Mizuno, T.; Moiseev, A. A.; Monte, C.; Monzani, M. E.; Moretti, E.; Morselli, A.; Murgia, S.; Nemmen, R.; Nuss, E.; Nymark, T.; Ohno, M.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Paciesas, W. S.; Paneque, D.; Panetta, J. H.; Pelassa, V.; Perkins, J. S.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T. A.; Preece, R.; Racusin, J. L.; Rainò, S.; Rando, R.; Rau, A.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; Romoli, C.; Roth, M.; Ryde, F.; Saz Parkinson, P. M.; Schalk, T. L.; Sgrò, C.; Siskind, E. J.; Sonbas, E.; Spandre, G.; Spinelli, P.; Suson, D. J.; Tajima, H.; Takahashi, H.; Takeuchi, Y.; Tanaka, Y.; Thayer, J. G.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Tierney, D.; Tinivella, M.; Torres, D. F.; Tosti, G.; Troja, E.; Tronconi, V.; Usher, T. L.; Vandenbroucke, J.; van der Horst, A. J.; Vasileiou, V.; Vianello, G.; Vitale, V.; von Kienlin, A.; Winer, B. L.; Wood, K. S.; Wood, M.; Xiong, S.; Yang, Z.</p> <p>2013-11-01</p> <p>In three years of observations since the beginning of nominal science operations in 2008 August, the Large Area Telescope (<span class="hlt">LAT</span>) on board the Fermi Gamma-Ray Space Telescope has observed high-energy (gsim 20 MeV) γ-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 GRBs above ~20 MeV. The first Fermi-<span class="hlt">LAT</span> catalog of GRBs is a compilation of these detections and provides a systematic study of high-energy emission from GRBs for the first time. To generate the catalog, we examined 733 GRBs detected by the Gamma-Ray Burst Monitor (GBM) on Fermi and processed each of them using the same analysis sequence. Details of the methodology followed by the <span class="hlt">LAT</span> collaboration for the GRB analysis are provided. We summarize the temporal and spectral properties of the <span class="hlt">LAT</span>-detected GRBs. We also discuss characteristics of <span class="hlt">LAT</span>-detected emission such as its delayed onset and longer duration compared with emission detected by the GBM, its power-law temporal decay at late times, and the fact that it is dominated by a power-law spectral component that appears in addition to the usual Band model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSM51A4236K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSM51A4236K"><span>Relationship between Relativistic <span class="hlt">Electron</span> <span class="hlt">Flux</span> in the Inner Magnetosphere and ULF Pulsation on the Ground Associated with Long-term Variations of Solar Wind</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kitamura, K.; Nagatsuma, T.; Troshichev, O. A.; Obara, T.; Koshiishi, H.; Saita, S.; Yoshikawa, A.; Yumoto, K.</p> <p>2014-12-01</p> <p>In the present study the relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> (0.59-1.18MeV) measured by Standard Dose Monitor (SDOM) onboard DRTS (KODAMA) satellite at the Geostationary Earth Orbit (GEO) is analyzed to investigate the long term (from 2002 to 2014) variations of the <span class="hlt">electron</span> <span class="hlt">flux</span> enhancement (REF) during the passage of Corotating Interaction Regions (CIRs) and/or Coronal Mass Ejection (CMEs). The long term variations of the REF clearly shows the 27-days period associated with the high speed solar wind velocity caused by the CIRs, whereas it is very few that the enhancement of REF lasts for several days after passage of CMEs. The 27-days period enhancement of REF represents the quite strong peak in 2003 when the high speed stream of the solar wind were quit active. We also conducted the same analysis for the Pc5 pulsations observed on the ground. The ground magnetic variations data globally observed by National Institute of Information and Communications Technology (NICT) and International Center for Space Weather Science and Education (ICSWSE) Kyushu University are used to investigate the long term variations of Pc5 power. The same signature in the REF variations is shown in the time variability of the Pc5 power on the ground. These results indicate that the solar wind condition strongly affects the acceleration process of the relativistic <span class="hlt">electron</span> <span class="hlt">flux</span> by the ULF wave. In particular the dependence of the REF and Pc5 variations on the sector structures and their seasonal variations strongly suggest that the relationship between Pc5 and REF variations could be controlled by the Russell-McPherron effect.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1355739-fermi-lat-observations-high-energy-behind-limb-solar-flares','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1355739-fermi-lat-observations-high-energy-behind-limb-solar-flares"><span>Fermi-<span class="hlt">LAT</span> Observations of High-energy Behind-the-limb Solar Flares</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ackermann, M.; Allafort, A.; Baldini, L.; ...</p> <p>2017-01-31</p> <p>In this paper, we report on the Fermi-<span class="hlt">LAT</span> detection of high-energy emission from the behind-the-limb (BTL) solar flares that occurred on 2013 October 11, and 2014 January 6 and September 1. The Fermi-<span class="hlt">LAT</span> observations are associated with flares from active regions originating behind both the eastern and western limbs, as determined by STEREO. All three flares are associated with very fast coronal mass ejections (CMEs) and strong solar energetic particle events. We present updated localizations of the >100 MeV photon emission, hard X-ray (HXR) and EUV images, and broadband spectra from 10 keV to 10 GeV, as well as microwavemore » spectra. We also provide a comparison of the BTL flares detected by Fermi-<span class="hlt">LAT</span> with three on-disk flares and present a study of some of the significant quantities of these flares as an attempt to better understand the acceleration mechanisms at work during these occulted flares. We interpret the HXR emission to be due to <span class="hlt">electron</span> bremsstrahlung from a coronal thin-target loop top with the accelerated <span class="hlt">electron</span> spectra steepening at semirelativistic energies. The >100 MeV gamma-rays are best described by a pion-decay model resulting from the interaction of protons (and other ions) in a thick-target photospheric source. In conclusion, the protons are believed to have been accelerated (to energies >10 GeV) in the CME environment and precipitate down to the photosphere from the downstream side of the CME shock and landed on the front side of the Sun, away from the original flare site and the HXR emission.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...835..219A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...835..219A"><span>Fermi-<span class="hlt">LAT</span> Observations of High-energy Behind-the-limb Solar Flares</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ackermann, M.; Allafort, A.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bissaldi, E.; Bonino, R.; Bottacini, E.; Bregeon, J.; Bruel, P.; Buehler, R.; Cameron, R. A.; Caragiulo, M.; Caraveo, P. A.; Cavazzuti, E.; Cecchi, C.; Charles, E.; Ciprini, S.; Costanza, F.; Cutini, S.; D’Ammando, F.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Drell, P. S.; Favuzzi, C.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Giglietto, N.; Giordano, F.; Giroletti, M.; Grenier, I. A.; Guillemot, L.; Guiriec, S.; Jogler, T.; Jóhannesson, G.; Kashapova, L.; Krucker, S.; Kuss, M.; La Mura, G.; Larsson, S.; Latronico, L.; Li, J.; Liu, W.; Longo, F.; Loparco, F.; Lubrano, P.; Magill, J. D.; Maldera, S.; Manfreda, A.; Mazziotta, M. N.; Mitthumsiri, W.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Negro, M.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; Pal’shin, V.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Petrosian, V.; Piron, F.; Principe, G.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, O.; Rubio da Costa, F.; Sgrò, C.; Simone, D.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Tajima, H.; Thayer, J. B.; Torres, D. F.; Troja, E.; Vianello, G.</p> <p>2017-02-01</p> <p>We report on the Fermi-<span class="hlt">LAT</span> detection of high-energy emission from the behind-the-limb (BTL) solar flares that occurred on 2013 October 11, and 2014 January 6 and September 1. The Fermi-<span class="hlt">LAT</span> observations are associated with flares from active regions originating behind both the eastern and western limbs, as determined by STEREO. All three flares are associated with very fast coronal mass ejections (CMEs) and strong solar energetic particle events. We present updated localizations of the >100 MeV photon emission, hard X-ray (HXR) and EUV images, and broadband spectra from 10 keV to 10 GeV, as well as microwave spectra. We also provide a comparison of the BTL flares detected by Fermi-<span class="hlt">LAT</span> with three on-disk flares and present a study of some of the significant quantities of these flares as an attempt to better understand the acceleration mechanisms at work during these occulted flares. We interpret the HXR emission to be due to <span class="hlt">electron</span> bremsstrahlung from a coronal thin-target loop top with the accelerated <span class="hlt">electron</span> spectra steepening at semirelativistic energies. The >100 MeV gamma-rays are best described by a pion-decay model resulting from the interaction of protons (and other ions) in a thick-target photospheric source. The protons are believed to have been accelerated (to energies >10 GeV) in the CME environment and precipitate down to the photosphere from the downstream side of the CME shock and landed on the front side of the Sun, away from the original flare site and the HXR emission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21694036','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21694036"><span>Signatures of the Dirac <span class="hlt">electron</span> in the <span class="hlt">flux</span> dependence of total persistent currents in isolated Aharonov-Bohm rings.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cotaescu, I I; Papp, E</p> <p>2007-0