Science.gov

Sample records for high energy sources

  1. High-Energy Neutrinos from Galactic Sources

    NASA Astrophysics Data System (ADS)

    Kappes, Alexander

    2011-10-01

    Even 100 years after the discovery of cosmic rays their origin remains a mystery. In recent years, TeV gamma-ray detectors have discovered and investigated many Galactic sources where particles are accelerated up to energies of 100 TeV. However, it has not been possible up to now to identify these sites unambiguously as sources of hadronic acceleration. The observation of cosmic high-energy neutrinos from these or other sources will be a smoking-gun evidence for the sites of the acceleration of cosmic rays.

  2. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1989-01-01

    Recent progress in the development of highly efficient coherent optical sources was reviewed. This work has focused on nonlinear frequency conversion of the highly coherent output of the non-planar ring laser oscillators developed earlier in the program, and includes high efficiency second harmonic generation and the operation of optical parametric oscillators for wavelength diversity and tunability.

  3. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1988-01-01

    Recent progress in the development of highly efficient coherent optical sources is reviewed. This work focusses on nonlinear frequency conversion of the highly coherent output of the Non-Planar Ring Laser Oscillators developed earlier in the program, and includes high efficiency second harmonic generation and the operation of optical parametric oscillators for wavelength diversity and tunability.

  4. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1987-01-01

    Investigations continue of diode-laser-pumped solid-state laser oscillators and nonlinear processes using them as sources. Diode laser array pumped Nd:YAG and Nd:glass lasers have been demonstrated. Theoretical studies of non-planar oscillators have been advanced, producing new designs which should be more resistant to feedback and offer better frequency stability. A monolithic, singly resonant Optical Parametric Oscillator in MgO:LiNbO3 has been operated.

  5. Very High-Energy Gamma-Ray Sources.

    ERIC Educational Resources Information Center

    Weekes, Trevor C.

    1986-01-01

    Discusses topics related to high-energy, gamma-ray astronomy (including cosmic radiation, gamma-ray detectors, high-energy gamma-ray sources, and others). Also considers motivation for the development of this field, the principal results to date, and future prospects. (JN)

  6. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1987-01-01

    Diode-laser-pumped solid-state laser oscillators and nonlinear processes were investigated. A new generation on nonplanar oscillator was fabricated, and it is anticipated that passive linewidths will be pushed to the kilohertz regime. A number of diode-pumped laser transitions were demonstrated in the rod configuration. Second-harmonic conversion efficiencies as high as 15% are routinely obtained in a servo-locked external resonant doubling crystal at 15 mW cw input power levels at 1064 nm.

  7. High-energy Neutrinos from Sources in Clusters of Galaxies

    NASA Astrophysics Data System (ADS)

    Fang, Ke; Olinto, Angela V.

    2016-09-01

    High-energy cosmic rays can be accelerated in clusters of galaxies, by mega-parsec scale shocks induced by the accretion of gas during the formation of large-scale structures, or by powerful sources harbored in clusters. Once accelerated, the highest energy particles leave the cluster via almost rectilinear trajectories, while lower energy ones can be confined by the cluster magnetic field up to cosmological time and interact with the intracluster gas. Using a realistic model of the baryon distribution and the turbulent magnetic field in clusters, we studied the propagation and hadronic interaction of high-energy protons in the intracluster medium. We report the cumulative cosmic-ray and neutrino spectra generated by galaxy clusters, including embedded sources, and demonstrate that clusters can contribute a significant fraction of the observed IceCube neutrinos above 30 TeV while remaining undetected in high-energy cosmic rays and γ rays for reasonable choices of parameters and source scenarios.

  8. ENERGY CONSERVATION THROUGH POINT SOURCE RECYCLE WITH HIGH TEMPERATURE HYPERFILTRATION

    EPA Science Inventory

    The report gives results of a study of energy conservation effects of point source recycle with high-temperature hyperfiltration (HF) in the textile industry. (HF and ultrafiltration (UF) are pressure-driven membrane processes which have potential for recycle of water, energy, an...

  9. Testing Special Relativity at High Energies with Astrophysical Sources

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    2007-01-01

    Since the group of Lorentz boosts is unbounded, there is a question as to whether Lorentz invariance (LI) holds to infinitely short distances. However, special and general relativity may break down at the Planck scale. Various quantum gravity scenarios such as loop quantum gravity, as well as some forms of string theory and extra dimension models may imply Lorentz violation (LV) at ultrahigh energies. The Gamma-Ray Large Area Space Telescope (GLAST), to be launched in mid-December, will measure the spectra of distant extragalactic sources of high energy gamma-rays, particularly active galactic nuclei and gamma-ray bursts. GLAST can look for energy-dependent gamma-ray propagation effects from such sources as a signal of Lorentz invariance violation. These sources may also exhibit the high energy cutoffs predicted to be the result of intergalactic annihilation interactions with low energy photons having a flux level as determined by various astronomical observations. With LV the threshold for such interactions can be significantly raised, changing the predicted absorption turnover in the observed spectrum of the sources. Stecker and Glashow have shown that the existence such absorption features in the spectra of extragalactic sources puts constraints on LV. Such constraints have important implications for some quantum gravity and large extra dimension models. Future spaceborne detectors dedicated to measuring gamma-ray polarization can look for birefringence effects as a possible signal of loop quantum gravity. A very small LV may also result in the modification or elimination of the GZK effect, thus modifying the spectrum of ultrahigh energy cosmic rays. This possibility can be explored with ground-based arrays such as Auger or with a space based detector system such as the proposed OWL satellite mission.

  10. High-energy diffraction microscopy at the advanced photon source

    SciTech Connect

    Lienert, U.; Li, S.; Hefferan, C.; Lind, J.; Suter, R.; Bernier, J.; Barton, N.; Brandes, M.; Mills, M.; Miller, M.; Jakobsen, B.; Pantleon, W.

    2012-02-28

    The status of the High Energy Diffraction Microscopy (HEDM) program at the 1-ID beam line of the Advanced Photon Source is reported. HEDM applies high energy synchrotron radiation for the grain and sub-grain scale structural and mechanical characterization of polycrystalline bulk materials in situ during thermomechanical loading. Case studies demonstrate the mapping of grain boundary topology, the evaluation of stress tensors of individual grains during tensile deformation and comparison to a finite element modeling simulation, and the characterization of evolving dislocation structure. Complementary information is obtained by post mortem electron microscopy on the same sample volume previously investigated by HEDM.

  11. Variable energy, high flux, ground-state atomic oxygen source

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Orient, Otto J. (Inventor)

    1987-01-01

    A variable energy, high flux atomic oxygen source is described which is comprised of a means for producing a high density beam of molecules which will emit O(-) ions when bombarded with electrons; a means of producing a high current stream of electrons at a low energy level passing through the high density beam of molecules to produce a combined stream of electrons and O(-) ions; means for accelerating the combined stream to a desired energy level; means for producing an intense magnetic field to confine the electrons and O(-) ions; means for directing a multiple pass laser beam through the combined stream to strip off the excess electrons from a plurality of the O(-) ions to produce ground-state O atoms within the combined stream; electrostatic deflection means for deflecting the path of the O(-) ions and the electrons in the combined stream; and, means for stopping the O(-) ions and the electrons and for allowing only the ground-state O atoms to continue as the source of the atoms of interest. The method and apparatus are also adaptable for producing other ground-state atoms and/or molecules.

  12. ULTRA-LOW-ENERGY HIGH-CURRENT ION SOURCE

    SciTech Connect

    Anders, Andre; Yushkov, Georgy Yu.; Baldwin, David A.

    2009-11-20

    The technical objective of the project was to develop an ultra-low-energy, high-intensity ion source (ULEHIIS) for materials processing in high-technology fields including semiconductors, micro-magnetics and optics/opto-electronics. In its primary application, this ion source can be incorporated into the 4Wave thin-film deposition technique called biased target ion-beam deposition (BTIBD), which is a deposition technique based on sputtering (without magnetic field, i.e., not the typical magnetron sputtering). It is a technological challenge because the laws of space charge limited current (Child-Langmuir) set strict limits of how much current can be extracted from a reservoir of ions, such as a suitable discharge plasma. The solution to the problem was an innovative dual-discharge system without the use of extraction grids.

  13. Development of a high-energy distributed energy source electromagnetic railgun with improved energy conversion efficiency

    SciTech Connect

    Tower, M.M.; Haight, C.H.

    1984-03-01

    Vought Corporation in cooperation with the Center for Electromechanics at the University of Texas (CEM-UT) has developed under sponsorship by the Defense Advanced Research Projects Agency (DARPA) and the Army Armament, Munitions, and Chemical Command (AMCCOM) a high-energy distributed energy source (DES) electromagnetic (EM) railgun accelerator. This paper discusses the development and current status of the DES railgun which has the design capability to launch projectile masses up to 60 grams to the 3-4 km/sec velocity regime with energy conversion efficiencies above 35 percent. These goals are being accomplished through utilization of scaled-energy CEM-UT railgun experiments for sequenced timing/staging and a full energy (575 kJ) design at Vought for high efficiency capability. The operational Vought single-pulse railgun forms the baseline for the full energy testing.

  14. Multiwavelength observations of unidentified high energy gamma ray sources

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.

    1993-01-01

    As was the case for COS B, the majority of high-energy (greater than 100 MeV) gamma-ray sources detected by the EGRET instrument on GRO are not immediately identifiable with cataloged objects at other wavelengths. These persistent gamma-ray sources are, next to the gamma-ray bursts, the least understood objects in the universe. Even a rudimentary understanding of their nature awaits identifications and follow-up work at other wavelengths to tell us what they are. The as yet unidentified sources are potentially the most interesting, since they may represent unrecognized new classes of astronomical objects, such as radio-quiet pulsars or new types of active galactic nuclei (AGN's). This two-year investigation is intended to support the analysis, correlation, and theoretical interpretation of data that we are obtaining at x ray, optical, and radio wavelengths in order to render the gamma-ray data interpretable. According to plan, in the first year concentration was on the identification and study of Geminga. The second year will be devoted to studies of similar unidentified gamma-ray sources which will become available in the first EGRET catalogs. The results obtained so far are presented in the two papers which are reproduced in the Appendix. In these papers, we discuss the pulse profiles of Geminga, the geometry and efficiency of the magnetospheric accelerator, the distance to Geminga, the implications for theories of polar cap heating, the effect of the magnetic field on the surface emission and environment of the neutron star, and possible interpretations of a radio-quiet Geminga. The implications of the other gamma-ray pulsars which were discovered to have high gamma-ray efficiency are also discussed, and the remaining unidentified COS B sources are attributed to a population of efficient gamma-ray sources, some of which may be radio quiet.

  15. Search for point sources of high energy neutrinos with Amanda

    SciTech Connect

    Ahrens, J.

    2002-08-01

    Report of search for likely point sources for neutrinos observed by the Amanda detector. Places intensity limits on observable point sources. This paper describes the search for astronomical sources of high-energy neutrinos using the AMANDA-B10 detector, an array of 302 photomultiplier tubes, used for the detection of Cherenkov light from upward traveling neutrino-induced muons, buried deep in ice at the South Pole. The absolute pointing accuracy and angular resolution were studied by using coincident events between the AMANDA detector and two independent telescopes on the surface, the GASP air Cherenkov telescope and the SPASE extensive air shower array. Using data collected from April to October of 1997 (130.1 days of livetime), a general survey of the northern hemisphere revealed no statistically significant excess of events from any direction. The sensitivity for a flux of muon neutrinos is based on the effective detection area for through-going muons. Averaged over the Northern sky, the effective detection area exceeds 10,000 m{sup 2} for E{sub {mu}} {approx} 10 TeV. Neutrinos generated in the atmosphere by cosmic ray interactions were used to verify the predicted performance of the detector. For a source with a differential energy spectrum proportional to E{sub {nu}}{sup -2} and declination larger than +40{sup o}, we obtain E{sup 2} (dN{sub {nu}}/dE) {le} 10{sup -6} GeV cm{sup -2} s{sup -1} for an energy threshold of 10 GeV.

  16. Progress in high-energy-class diode laser pump sources

    NASA Astrophysics Data System (ADS)

    Crump, P.; Frevert, C.; Bugge, F.; Knigge, S.; Erbert, G.; Tränkle, G.; Pietrzak, A.; Hüslewede, R.; Zorn, M.; Sebastian, J.; Lotz, J.; Fassbender, W.; Neukum, J.; Körner, J.; Hein, J.; Töpfer, T.

    2015-03-01

    A new generation of diode-pumped high-energy-class solid-state laser facilities is in development that generate multijoule pulse energies at around 10 Hz. Currently deployed quasi-continuous-wave (QCW) diode lasers deliver average inpulse pump powers of around 300 W per bar. Increased power-per-bar helps to reduce the system size, complexity and cost per Joule and the increased pump brilliance also enables more efficient operation of the solid state laser itself. It has been shown in recent studies, that optimized QCW diode laser bars centered at 940…980 nm can operate with an average in-pulse power of > 1000 W per bar, triple that of commercial sources. When operated at pulsed condition of 1 ms, 10 Hz, this corresponds to > 1 J/bar. We review here the status of these high-energy-class pump sources, showing how the highest powers are enabled by using long resonators (4…6 mm) for improved cooling and robustly passivated output facets for high reliability. Results are presented for prototype passively-cooled single bar assemblies and monolithic stacked QCW arrays. We confirm that 1 J/bar is sustained for fast-axis collimated stacks with a bar pitch of 1.7 mm, with narrow lateral far field angle (< 12° with 95% power) and spectral width (< 12 nm with 95% power). Such stacks are anticipated to enable Joule/bar pump densities to be used near-term in commercial high power diode laser systems. Finally, we briefly summarize the latest status of research into bars with higher efficiencies, including studies into operation at sub-zero temperatures (-70°C), which also enables higher powers and narrower far field and spectra.

  17. Non-ionic PAG behavior under high energy exposure sources

    NASA Astrophysics Data System (ADS)

    Lawson, Richard A.; Noga, David E.; Tolbert, Laren M.; Henderson, Clifford L.

    2009-03-01

    A series of non-ionic PAGs were synthesized and their acid generation efficiency measured under deep ultraviolet and electron beam exposures. The acid generation efficiency was determined with an on-wafer method that uses spectroscopic ellipsometry to measure the absorbance of an acid sensitive dye (Coumarin 6). Under DUV exposures, common ionic onium salt PAGs showed excellent photoacid generation efficiency, superior to most non-ionic PAGS tested in this work. In contrast, under 100 keV high energy e-beam exposures, almost all of the non-ionic PAGs showed significantly better acid generation performance than the ionic onium salt PAGs tested. In particular, one non-ionic PAG showed almost an order of magnitude improvement in the Dill C acid generation rate constant as compared to a triarylsulfonium PAG. The high energy acid generation efficiency was found to correlate well with the electron affinity of the PAGs, suggesting that improvements in PAG design can be predicted. Non-ionic PAGs merit further investigation as a means for producing higher sensitivity resists under high energy exposure sources.

  18. High Energy Density Science at the Linac Coherent Light Source

    SciTech Connect

    Lee, R W

    2007-10-19

    High energy density science (HEDS), as a discipline that has developed in the United States from National Nuclear Security Agency (NNSA)-sponsored laboratory research programs, is, and will remain, a major component of the NNSA science and technology strategy. Its scientific borders are not restricted to NNSA. 'Frontiers in High Energy Density Physics: The X-Games of Contemporary Science' identified numerous exciting scientific opportunities in this field, while pointing to the need for a overarching interagency plan for its evolution. Meanwhile, construction of the first x-ray free-electron laser, the Office-of-Science-funded Linear Coherent Light Source-LCLS: the world's first free electron x-ray laser, with 100-fsec time resolution, tunable x-ray energies, a high rep rate, and a 10 order-of-magnitude increase in brightness over any other x-ray source--led to the realization that the scientific needs of NNSA and the broader scientific community could be well served by an LCLS HEDS endstation employing both short-pulse and high-energy optical lasers. Development of this concept has been well received in the community. NNSA requested a workshop on the applicability of LCLS to its needs. 'High Energy Density Science at the LCLS: NNSA Defense Programs Mission Need' was held in December 2006. The workshop provided strong support for the relevance of the endstation to NNSA strategic requirements. The range of science that was addressed covered a wide swath of the vast HEDS phase space. The unique possibilities provided by the LCLS in areas of intense interest to NNSA Defense Programs were discussed. The areas of focus included warm dense matter and equations of state, hot dense matter, and behavior of high-pressure materials under conditions of high strain-rate and extreme dynamic loading. Development of new and advanced diagnostic techniques was also addressed. This report lays out the relevant science, as brief summaries (Ch. II), expanded descriptions (Ch. V), and a

  19. High energy mode locked fiber oscillators for high contrast, high energy petawatt laser seed sources

    SciTech Connect

    Dawson, J W; Messerly, M J; An, J; Kim, D; Barty, C J

    2006-06-15

    In a high-energy petawatt laser beam line the ASE pulse contrast is directly related to the total laser gain. Thus a more energetic input pulse will result in increased pulse contrast at the target. We have developed a mode-locked fiber laser with high quality pulses and energies exceeding 25nJ. We believe this 25nJ result is scalable to higher energies. This oscillator has no intra-cavity dispersion compensation, which yields an extremely simple, and elegant laser configuration. We will discuss the design of this laser, our most recent results and characterization of all the key parameters relevant to it use as a seed laser. Our oscillator is a ring cavity mode-locked fiber laser [1]. These lasers operate in a self-similar pulse propagation regime characterized by a spectrum that is almost square. This mode was found theoretically [2] to occur only in the positive dispersion regime. Further increasing positive dispersion should lead to increasing pulse energy [2]. We established that the positive dispersion required for high-energy operation was approximately that of 2m of fiber. To this end, we constructed a laser cavity similar to [1], but with no gratings and only 2m of fiber, which we cladding pumped in order to ensure sufficient pump power was available to achieve mode-locked operation. A schematic of the laser is shown in figure 1 below. This laser produced low noise 25nJ pulses with a broad self similar spectrum (figure 2) and pulses that could be de-chirped to <100fs (figure 3). Pulse contrast is important in peta-watt laser systems. A major contributor to pulse contrast is amplified spontaneous emission (ASE), which is proportional to the gain in the laser chain. As the oscillator strength is increased, the required gain to reach 1PW pulses is decreased, reducing ASE and improving pulse contrast. We believe these lasers can be scaled in a stable fashion to pulse energies as high as 100nJ and have in fact seen 60nJ briefly in our lab, which is work still

  20. Optimum target source term estimation for high energy electron accelerators

    NASA Astrophysics Data System (ADS)

    Nayak, M. K.; Sahu, T. K.; Nair, Haridas G.; Nandedkar, R. V.; Bandyopadhyay, Tapas; Tripathi, R. M.; Hannurkar, P. R.

    2016-05-01

    Optimum target for bremsstrahlung emission is defined as the thickness of the target material, which produces maximum bremsstrahlung yield, on interaction of electron with the target. The bremsstrahlung dose rate per unit electron beam power at a distance of 1 m from the target material gives the optimum target source term. In the present work, simulations were performed for three different electron energies, 450, 1000 and 2500 MeV using EGSnrc Monte-Carlo code to determine the optimum thickness. An empirical relation for optimum target as a function of electron energy and atomic number of the target materials is found out from results. Using the simulated optimum target thickness, experiments are conducted to determine the optimum target source term. For the experimental determination, two available electron energies, 450 MeV and 550 MeV from booster synchrotron of Indus facility is used. The optimum target source term for these two energies are also simulated. The experimental and simulated source term are found to be in very good agreement within ±3%. Based on the agreement of the simulated source term with the experimental source term at 450 MeV and 550 MeV, the same simulation methodology is used to simulate optimum target source term up to 2500 MeV. The paper describes the simulations and experiments carried out on optimum target bremsstrahlung source term and the results obtained.

  1. Active Galactic Nuclei:. Sources for Ultra High Energy Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Biermann, P. L.; Becker, J. K.; Caramete, L.; Gergely, L.; Mariş, I. C.; Meli, A.; de Souza, V.; Stanev, T.

    Ultra high energy cosmic ray events presently show a spectrum, which we interpret here as galactic cosmic rays due to a starburst, in the radio galaxy Cen A which is pushed up in energy by the shock of a relativistic jet. The knee feature and the particles with energy immediately higher in galactic cosmic rays then turn into the bulk of ultra high energy cosmic rays. This entails that all ultra high energy cosmic rays are heavy nuclei. This picture is viable if the majority of the observed ultra high energy events come from the radio galaxy Cen A, and are scattered by intergalactic magnetic fields across much of the sky.

  2. High-energy gamma-ray sources of cosmological origin

    NASA Astrophysics Data System (ADS)

    Brun, Pierre; Cohen-Tanugi, Johann

    2016-06-01

    The current generation of instruments in gamma-ray astrophysics launched a new era in the search for a dark matter signal in the high-energy sky. Such searches are said indirect, in the sense that the presence of a dark matter particle is inferred from the detection of products of its pair-annihilation or decay. They have recently started to probe the natural domain of existence for weakly interacting massive particles (WIMPs), the favorite dark matter candidates today. In this article, we review the basic framework for indirect searches and we present a status of current limits obtained with gamma-ray observations. We also devote a section to another possible class of cosmological gamma-ray sources, primordial black holes, also considered as a potential constituent of dark matter. xml:lang="fr"

  3. Energy Sources (Energy/Power). Industrial Arts, Senior High--Level II. North Dakota Senior High Industrial Arts Curriculum Guides.

    ERIC Educational Resources Information Center

    Lawrence, Allen; And Others

    This course guide for an energy sources course is one of four developed for the energy/power area in the North Dakota senior high industrial arts education program. (Eight other guides are available for two other areas of Industrial Arts--graphic communications and production.) Part 1 provides such introductory information as a definition and…

  4. HIGH INTENSITY LOW-ENERGY POSITRON SOURCE AT JEFFERSON

    SciTech Connect

    Serkan Golge, Bogdan Wojtsekhowski, Branislav Vlahovic

    2012-07-01

    We present a novel concept of a low-energy e{sup +} source with projected intensity on the order of 10{sup 10} slow e{sup +}/s. The key components of this concept are a continuous wave e{sup -} beam, a rotating positron-production target, a synchronized raster/anti-raster, a transport channel, and extraction of e{sup +} into a field-free area through a magnetic plug for moderation in a cryogenic solid. Components were designed in the framework of GEANT4-based (G4beamline) Monte Carlo simulation and TOSCA magnetic field calculation codes. Experimental data to demonstrate the effectiveness of the magnetic plug is presented.

  5. Axion-Like particles from extragalactic High Energy sources

    NASA Astrophysics Data System (ADS)

    Conrad, J.; Meyer, M.; Montanino, D.

    2016-05-01

    Background radiation fields (such as Extragalactic Background Light, EBL, or Cosmic Microwave Background, CMB) pervade the Universe. Above a certain energy any gamma ray flux emitted by an extragalactic source should be attenuated by the process γ+ γ(bgk) → e + + e - pair production. We have considered a scenario in which the photons are partly converted into light Axion Like Particles (ALPs) in the local magnetic field of an (extragalactic) source. Then, while the unconverted fraction of photons undergo absorption, the ALP component travel to our galaxy where is converted back to photons by the galactic magnetic field resulting in a sort of cosmic light shining through wall effect. In particular, we have considered two scenarios: 1) conversion in the turbulent magnetic field inside a galaxy cluster; and 2) conversion of photons in the coherent magnetic field at parsec scales in a Blazar jet. Afterwards, we have also analyzed mock data coming from a hypothetical Imaging Air Cherenkov Telescopes (IACT) array with characteristics similar to the Cherenkov Telescope Array (CTA) and we have investigated the dependence of the sensitivity to detect a gamma ray excess on the magnetic field parameters.

  6. Radioistopes to Solar to High Energy Accelerators - Chip-Scale Energy Sources

    NASA Astrophysics Data System (ADS)

    Lal, Amit

    2013-12-01

    This talk will present MEMS based power sources that utilize radioisotopes, solar energy, and potentially nuclear energy through advancements in integration of new structures and materials within MEMS. Micro power harvesters can harness power from vibration, radioisotopes, light, sound, and biology may provide pathways to minimize or even eliminate batteries in sensor nodes. In this talk work on radioisotope thin films for MEMS will be include the self-reciprocating cantilever, betavoltaic cells, and high DC voltages. The self-reciprocating cantilever energy harvester allows small commercially viable amounts of radioisotopes to generate mW to Watts of power so that very reliable power sources that last 100s of years are possible. The tradeoffs between reliability and potential stigma with radioisotopes allow one to span a useful design space with reliability as a key parameter. These power sources provide pulsed power at three different time scales using mechanical, RF, and static extraction of energy from collected charge. Multi-use capability, both harvesting radioisotope power and local vibration energy extends the reliability of micro-power sources further.

  7. Reliable pump sources for high-energy class lasers

    NASA Astrophysics Data System (ADS)

    Wölz, Martin; Pietrzak, Agnieszka; Kindsvater, Alex; Wolf, Jürgen; Meusel, Jens; Hülsewede, Ralf; Sebastian, Jürgen

    2015-05-01

    High-energy class laser systems operating at high average power are destined to serve fundamental research and commercial applications. System cost is becoming decisive, and JENOPTIK supports future developments with the new range of 500 W quasi-continuous wave (QCW) laser diode bars. In response to different strategies in implementing high-energy class laser systems, pump wavelengths of 880 nm and 940 nm are available. The higher power output per chip increases array irradiance and reduces the size of the optical system, lowering system cost. Reliability testing of the 880 nm laser diode bar has shown 1 Gshots at 500 W and 300 μs pulse duration, with insignificant degradation. Parallel operation in eight-bar diode stacks permits 4 kW pulse power operation. A new high-density QCW package is under development at JENOPTIK. Cost and reliability being the design criteria, the diode stacks are made by simultaneous soldering of submounts and insulating ceramic. The new QCW stack assembly technology permits an array irradiance of 12.5 kW/cm². We present the current state of the development, including laboratory data from prototypes using the new 500 W laser diode in dense packaging.

  8. Type IIn supernovae as sources of high energy astrophysical neutrinos

    NASA Astrophysics Data System (ADS)

    Zirakashvili, V. N.; Ptuskin, V. S.

    2016-05-01

    It is shown that high-energy astrophysical neutrinos observed in the IceCube experiment can be produced by protons accelerated in extragalactic Type IIn supernova remnants by shocks propagating in the dense circumstellar medium. The nonlinear diffusive shock acceleration model is used for description of particle acceleration. We calculate the neutrino spectrum produced by an individual Type IIn supernova and the spectrum of neutrino background produced by IIn supernovae in the expanding Universe. We also found that the arrival direction of one Icecube neutrino candidate (track event 47) is at 1.35° from Type IIn supernova 2005bx.

  9. Constraining sources of ultra high energy cosmic rays using high energy observations with the Fermi satellite

    SciTech Connect

    Pe'er, Asaf; Loeb, Abraham E-mail: aloeb@cfa.harvard.edu

    2012-03-01

    We analyze the conditions that enable acceleration of particles to ultra-high energies, ∼ 10{sup 20} eV (UHECRs). We show that broad band photon data recently provided by WMAP, ISOCAM, Swift and Fermi satellites, yield constraints on the ability of active galactic nuclei (AGN) to produce UHECRs. The high energy (MeV–GeV) photons are produced by Compton scattering of the emitted low energy photons and the cosmic microwave background or extra-galactic background light. The ratio of the luminosities at high and low photon energies can therefore be used as a probe of the physical conditions in the acceleration site. We find that existing data excludes core regions of nearby radio-loud AGN as possible acceleration sites of UHECR protons. However, we show that giant radio lobes are not excluded. We apply our method to Cen A, and show that acceleration of protons to ∼ 10{sup 20} eV can only occur at distances ∼>100 kpc from the core.

  10. High contrast Kr gas jet Kα x-ray source for high energy density physics experimentsa)

    NASA Astrophysics Data System (ADS)

    Kugland, N. L.; Neumayer, P.; Döppner, T.; Chung, H.-K.; Constantin, C. G.; Girard, F.; Glenzer, S. H.; Kemp, A.; Niemann, C.

    2008-10-01

    A high contrast 12.6keV Kr Kα source has been demonstrated on the petawatt-class Titan laser facility using strongly clustering Kr gas jet targets. The contrast ratio (Kα to continuum) is 65, with a competitive ultrashort pulse laser to x-ray conversion efficiency of 10-5. Filtered shadowgraphy indicates that the Kr Kα and Kβ x rays are emitted from a roughly 1×2mm2 emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70eV (i.e., mean ionization state 13-16), based on the observed ratio of Kα to Kβ. Kr gas jets provide a debris-free high energysource for time-resolved diagnosis of dense matter.

  11. High-energy sources before INTEGRAL. INTEGRAL reference catalog

    NASA Astrophysics Data System (ADS)

    Ebisawa, K.; Bourban, G.; Bodaghee, A.; Mowlavi, N.; Courvoisier, T. J.-L.

    2003-11-01

    We describe the INTEGRAL reference catalog which classifies previously known bright X-ray and gamma-ray sources before the launch of INTEGRAL. These sources are, or have been at least once, brighter than ~ 1 mCrab above 3 keV, and are expected to be detected by INTEGRAL. This catalog is being used in the INTEGRAL Quick Look Analysis to discover new sources or significantly variable sources. We compiled several published X-ray and gamma-ray catalogs, and surveyed recent publications for new sources. Consequently, there are 1122 sources in our INTEGRAL reference catalog. In addition to the source positions, we show an approximate spectral model and expected flux for each source, based on which we derive expected INTEGRAL counting rates. Assuming the default instrument performances and at least ~ 105 s exposure time for any part of the sky, we expect that INTEGRAL will detect at least ~ 700 sources below 10 keV and ~ 400 sources above 20 keV over the mission life. The Catalog is available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?/A+A/411/L59

  12. High fidelity nuclear energy system optimization towards an environmentally benign, sustainable, and secure energy source.

    SciTech Connect

    Tsvetkov, Pavel Valeryevich; Rodriguez, Salvador B.; Ames, David E., II; Rochau, Gary Eugene

    2009-09-01

    The impact associated with energy generation and utilization is immeasurable due to the immense, widespread, and myriad effects it has on the world and its inhabitants. The polar extremes are demonstrated on the one hand, by the high quality of life enjoyed by individuals with access to abundant reliable energy sources, and on the other hand by the global-scale environmental degradation attributed to the affects of energy production and use. Thus, nations strive to increase their energy generation, but are faced with the challenge of doing so with a minimal impact on the environment and in a manner that is self-reliant. Consequently, a revival of interest in nuclear energy has followed, with much focus placed on technologies for transmuting nuclear spent fuel. The performed research investigates nuclear energy systems that optimize the destruction of nuclear waste. In the context of this effort, nuclear energy system is defined as a configuration of nuclear reactors and corresponding fuel cycle components. The proposed system has unique characteristics that set it apart from other systems. Most notably the dedicated High-Energy External Source Transmuter (HEST), which is envisioned as an advanced incinerator used in combination with thermal reactors. The system is configured for examining environmentally benign fuel cycle options by focusing on minimization or elimination of high level waste inventories. Detailed high-fidelity exact-geometry models were developed for representative reactor configurations. They were used in preliminary calculations with Monte Carlo N-Particle eXtented (MCNPX) and Standardized Computer Analysis for Licensing Evaluation (SCALE) code systems. The reactor models have been benchmarked against existing experimental data and design data. Simulink{reg_sign}, an extension of MATLAB{reg_sign}, is envisioned as the interface environment for constructing the nuclear energy system model by linking the individual reactor and fuel component sub

  13. Thulium heat source for high-endurance and high-energy density power systems

    NASA Astrophysics Data System (ADS)

    Walter, C. E.; Kammeraad, J. E.; Vankonynenburg, R.; Vansant, J. H.

    1991-05-01

    We are studying the performance characteristics of radioisotope heat source designs for high-endurance and high-energy-density power systems that use thulium-170. Heat sources in the power range of 5 to 50 kW(sub th) coupled with a power conversion efficiency of approximately 30 percent, can easily satisfy current missions for autonomous underwater vehicles. New naval missions will be possible because thulium isotope power systems have a factor of one-to-two hundred higher endurance and energy density than chemical and electrochemical systems. Thulium-170 also has several other attractive features, including the fact that it decays to stable ytterbium-170 with a half-life of four months. For terrestrial applications, refueling on that time scale should be acceptable in view of the advantage of its benign decay. The heat source designs we are studying account for the requirements of isotope production, shielding, and integration with power conversion components. These requirements are driven by environmental and safety considerations. Thulium is present in the form of thin refractory thulia disks that allow power conversion at high peak temperature. We give estimates of power system state points, performance, mass, and volume characteristics. Monte Carlo radiation analysis provides a detailed assessment of shield requirements and heat transfer under normal and distressed conditions is also considered.

  14. Thulium heat source for high-endurance and high-energy density power systems

    SciTech Connect

    Walter, C.E.; Kammeraad, J.E.; Van Konynenburg, R.; VanSant, J.H.

    1991-05-01

    We are studying the performance characteristics of radioisotope heat source designs for high-endurance and high-energy-density power systems that use thulium-170. Heat sources in the power range of 5--50 kW{sub th} coupled with a power conversion efficiency of {approximately}30%, can easily satisfy current missions for autonomous underwater vehicles. New naval missions will be possible because thulium isotope power systems have a factor of one-to-two hundred higher endurance and energy density than chemical and electrochemical systems. Thulium-170 also has several other attractive features, including the fact that it decays to stable ytterbium-170 with a half-life of four months. For terrestrial applications, refueling on that time scale should be acceptable in view of the advantage of its benign decay. The heat source designs we are studying account for the requirements of isotope production, shielding, and integration with power conversion components. These requirements are driven by environmental and safety considerations. Thulium is present in the form of thin refractory thulia disks that allow power conversion at high peak temperature. We give estimates of power system state points, performance, mass, and volume characteristics. Monte Carlo radiation analysis provides a detailed assessment of shield requirements and heat transfer under normal and distressed conditions is also considered. 11 refs., 7 figs., 4 tabs.

  15. POLARIZED ION SOURCES FOR HIGH ENERGY ACCELERATORS AND COLLIDERS

    SciTech Connect

    ZELENSKI,A.N.

    2000-10-16

    The recent progress in polarized ion source development is reviewed. In dc operation a 1.0 mA polarized H{sup -} ion current is now available from the Optically-Pumped Polarized Ion Source (OPPIS) . In pulsed operation a 10 mA polarized H{sup -} ion current was demonstrated at the TRIUMF pulsed OPPIS test bench and a 3.5 mA peak current was obtained from an Atomic Beam Source (ABS) at the INR Moscow test bench. The possibilities for future improvements with both techniques are discussed. A new OPPIS for RHIC spin physics is described. The OPPIS reliably delivered polarized beam for the polarized run at RHIC. The results obtained with a new pulsed ABS injector for the IUCF Cooler Ring are also discussed.

  16. POLARIZED ION SOURCES FOR HIGH ENERGY ACCELERATORS AND COLLIDERS

    SciTech Connect

    ZELENSKI,A.N.

    2000-10-16

    The recent progress in polarized ion source development is reviewed. In dc operation a 1.0 mA polarized H{sup -} ion current is now available from the Optically-Pumped Polarized Ion Source (OPPIS). In pulsed operation a 10 mA polarized H{sup -} ion current was demonstrated at the TRIUMF pulsed OPPIS test bench and a 3.5 mA peak current was obtained from an Atomic Beam Source (ABS) at the INR Moscow test bench. The possibilities for future improvements with both techniques are discussed. A new OPPIS for RHIC spin physics is described. The OPPIS reliably delivered polarized beam for the polarized run at RHIC. The results obtained with a new pulsed ABS injector for the IUCF Cooler Ring are also discussed.

  17. Contribution from individual nearby sources to the spectrum of high-energy cosmic-ray electrons

    NASA Astrophysics Data System (ADS)

    Sedrati, R.; Attallah, R.

    2014-04-01

    In the last few years, very important data on high-energy cosmic-ray electrons and positrons from high-precision space-born and ground-based experiments have attracted a great deal of interest. These particles represent a unique probe for studying local comic-ray accelerators because they lose energy very rapidly. These energy losses reduce the lifetime so drastically that high-energy cosmic-ray electrons can attain the Earth only from rather local astrophysical sources. This work aims at calculating, by means of Monte Carlo simulation, the contribution from some known nearby astrophysical sources to the cosmic-ray electron/positron spectra at high energy (≥ 10 GeV). The background to the electron energy spectrum from distant sources is determined with the help of the GALPROP code. The obtained numerical results are compared with a set of experimental data.

  18. A search for cosmic sources of high energy neutrinos with small underground detectors

    NASA Technical Reports Server (NTRS)

    Berezinsky, V. S.; Castagnoli, C.; Galeotti, P.

    1985-01-01

    On the basis of standard source calculations of high energy neutrino fluxes, some models of astrophysical object (single stars and binary systems) are discussed from which a detectable muon flux is expected in small underground detectors.

  19. High fidelity nuclear energy system optimization towards an environmentally benign, sustainable, and secure energy source.

    SciTech Connect

    Tsvetkov, Pavel Valeryevich; Rodriguez, Salvador B.; Ames, David E., II; Rochau, Gary Eugene

    2010-10-01

    A new high-fidelity integrated system method and analysis approach was developed and implemented for consistent and comprehensive evaluations of advanced fuel cycles leading to minimized Transuranic (TRU) inventories. The method has been implemented in a developed code system integrating capabilities of Monte Carlo N - Particle Extended (MCNPX) for high-fidelity fuel cycle component simulations. In this report, a Nuclear Energy System (NES) configuration was developed to take advantage of used fuel recycling and transmutation capabilities in waste management scenarios leading to minimized TRU waste inventories, long-term activities, and radiotoxicities. The reactor systems and fuel cycle components that make up the NES were selected for their ability to perform in tandem to produce clean, safe, and dependable energy in an environmentally conscious manner. The diversity in performance and spectral characteristics were used to enhance TRU waste elimination while efficiently utilizing uranium resources and providing an abundant energy source. A computational modeling approach was developed for integrating the individual models of the NES. A general approach was utilized allowing for the Integrated System Model (ISM) to be modified in order to provide simulation for other systems with similar attributes. By utilizing this approach, the ISM is capable of performing system evaluations under many different design parameter options. Additionally, the predictive capabilities of the ISM and its computational time efficiency allow for system sensitivity/uncertainty analysis and the implementation of optimization techniques.

  20. High energy supercontinuum sources using tapered photonic crystal fibers for multispectral photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Bondu, Magalie; Brooks, Christopher; Jakobsen, Christian; Oakes, Keith; Moselund, Peter Morten; Leick, Lasse; Bang, Ole; Podoleanu, Adrian

    2016-06-01

    We demonstrate a record bandwidth high energy supercontinuum source suitable for multispectral photoacoustic microscopy. The source has more than 150 nJ/10 nm bandwidth over a spectral range of 500 to 1600 nm. This performance is achieved using a carefully designed fiber taper with large-core input for improved power handling and small-core output that provides the desired spectral range of the supercontinuum source.

  1. High energy supercontinuum sources using tapered photonic crystal fibers for multispectral photoacoustic microscopy.

    PubMed

    Bondu, Magalie; Brooks, Christopher; Jakobsen, Christian; Oakes, Keith; Moselund, Peter Morten; Leick, Lasse; Bang, Ole; Podoleanu, Adrian

    2016-06-01

    We demonstrate a record bandwidth high energy supercontinuum source suitable for multispectral photoacoustic microscopy. The source has more than 150  nJ/10  nm bandwidth over a spectral range of 500 to 1600 nm. This performance is achieved using a carefully designed fiber taper with large-core input for improved power handling and small-core output that provides the desired spectral range of the supercontinuum source. PMID:26836298

  2. CONSTRAINTS ON THE SOURCE OF ULTRA-HIGH-ENERGY COSMIC RAYS USING ANISOTROPY VERSUS CHEMICAL COMPOSITION

    SciTech Connect

    Liu, Ruo-Yu; Wang, Xiang-Yu; Taylor, Andrew M.; Lemoine, Martin; Waxman, Eli

    2013-10-20

    The joint analysis of anisotropy signals and chemical composition of ultra-high-energy cosmic rays offers strong potential for shedding light on the sources of these particles. Following up on an earlier idea, this paper studies the anisotropies produced by protons of energy >E/Z, assuming that anisotropies at energy >E have been produced by nuclei of charge Z, which share the same magnetic rigidity. We calculate the number of secondary protons produced through photodisintegration of the primary heavy nuclei. Making the extreme assumption that the source does not inject any proton, we find that the source(s) responsible for anisotropies such as reported by the Pierre Auger Observatory should lie closer than ∼20-30, 80-100, and 180-200 Mpc if the anisotropy signal is mainly composed of oxygen, silicon, and iron nuclei, respectively. A violation of this constraint would otherwise result in the secondary protons forming a more significant anisotropy signal at lower energies. Even if the source were located closer than this distance, it would require an extraordinary metallicity ∼> 120, 1600, and 1100 times solar metallicity in the acceleration zone of the source, for oxygen, silicon, and iron, respectively, to ensure that the concomitantly injected protons do not produce a more significant low-energy anisotropy. This offers interesting prospects for constraining the nature and the source of ultra-high-energy cosmic rays with the increase in statistics expected from next-generation detectors.

  3. Energy: Sources and Issues. Science Syllabus for Middle and Junior High Schools. Block I.

    ERIC Educational Resources Information Center

    Cappiello, Jane E.; O'Neil, Karen E.

    This syllabus provides a list of concepts and understandings related to four areas of energy. They are: (1) the nature of energy (an energy definition, basic categories of energy, forms of energy, laws of energy conversion, and measuring energy); (2) energy sources of the past and present (history of energy use and present major sources of…

  4. The HEAO 1 A-4 catalog of high-energy X-ray sources

    NASA Technical Reports Server (NTRS)

    Levine, A. M.; Lang, F. L.; Lewin, W. H. G.; Primini, F. A.; Dobson, C. A.; Doty, J. P.; Hoffman, J. A.; Howe, S. K.; Scheepmaker, A.; Wheaton, W. A.

    1984-01-01

    Results are reported from an all-sky survey carried out at high X-ray energies (13-180 keV) from August 1977 until January 1979 using data obtained with the UCSD/MIT Hard X-Ray and Low-Energy Gamma-Ray Instrument on the HEAO 1 satellite. Visual displays are presented which indicate qualitatively the location, intensities, and time variability of the detected high-energy X-ray sources. A model-dependent procedure for the quantitative analysis of the sky survey data is described. The results of this procedure are presented in tabular form and include fitted count rates in four broad energy bands for about 70 sources. All sources which were detected at a level of statistical significance of not less than about 6 sigma were clearly evident in the visual displays of sky survey data. The survey is therefore complete, except in regions of source confusion, down to an intensity level of about 1/75 of the Crab Nebula in the 13-80 keV band. Forty-four sources were detected in the 40-80 keV energy band, and 14 were detected in the 80-180 keV band. Although most of the detected sources are galactic, seven are extragalactic.

  5. Using the Virtual Observatory: multi-instrument, multi-wavelength study of high-energy sources

    NASA Astrophysics Data System (ADS)

    Derrière, S.; Goosmann, R. W.; Bot, C.; Bonnarel, F.

    2014-12-01

    This paper presents a tutorial explaining the use of Virtual Observatory tools in high energy astrophysics. Most of the tools used in this paper were developed at the Strasbourg astronomical Data Center and we show how they can be applied to conduct a multi-instrument, multi-wavelength analysis of sources detected by the High Energy Stereoscopic System and the Fermi Large Area Telescope. The analysis involves queries of different data catalogs, selection and cross-correlation techniques on multi-waveband images, and the construction of high energy color-color plots and multi-wavelength spectra. The tutorial is publicly available on the website of the European Virtual Observatory project.

  6. Evaluation of high-energy brachytherapy source electronic disequilibrium and dose from emitted electrons

    SciTech Connect

    Ballester, Facundo; Granero, Domingo; Perez-Calatayud, Jose; Melhus, Christopher S.; Rivard, Mark J.

    2009-09-15

    Purpose: The region of electronic disequilibrium near photon-emitting brachytherapy sources of high-energy radionuclides ({sup 60}Co, {sup 137}Cs, {sup 192}Ir, and {sup 169}Yb) and contributions to total dose from emitted electrons were studied using the GEANT4 and PENELOPE Monte Carlo codes. Methods: Hypothetical sources with active and capsule materials mimicking those of actual sources but with spherical shape were examined. Dose contributions due to source photons, x rays, and bremsstrahlung; source {beta}{sup -}, Auger electrons, and internal conversion electrons; and water collisional kerma were scored. To determine if conclusions obtained for electronic equilibrium conditions and electron dose contribution to total dose for the representative spherical sources could be applied to actual sources, the {sup 192}Ir mHDR-v2 source model (Nucletron B.V., Veenendaal, The Netherlands) was simulated for comparison to spherical source results and to published data. Results: Electronic equilibrium within 1% is reached for {sup 60}Co, {sup 137}Cs, {sup 192}Ir, and {sup 169}Yb at distances greater than 7, 3.5, 2, and 1 mm from the source center, respectively, in agreement with other published studies. At 1 mm from the source center, the electron contributions to total dose are 1.9% and 9.4% for {sup 60}Co and {sup 192}Ir, respectively. Electron emissions become important (i.e., >0.5%) within 3.3 mm of {sup 60}Co and 1.7 mm of {sup 192}Ir sources, yet are negligible over all distances for {sup 137}Cs and {sup 169}Yb. Electronic equilibrium conditions along the transversal source axis for the mHDR-v2 source are comparable to those of the spherical sources while electron dose to total dose contribution are quite different. Conclusions: Electronic equilibrium conditions obtained for spherical sources could be generalized to actual sources while electron contribution to total dose depends strongly on source dimensions, material composition, and electron spectra.

  7. Energy-harvesting power sources for very-high-G gun-fired munitions

    NASA Astrophysics Data System (ADS)

    Rastegar, J.; Murray, R.; Pereira, C.; Nguyen, H.-L.

    2010-04-01

    Several novel classes of piezoelectric-based energy-harvesting power sources are presented for very high-G gun-fired munitions (40,000 - 240,000 Gs). The power sources are designed to harvest energy from the firing acceleration and in certain applications also from in-flight vibrations. The harvested energy is converted to electrical energy for powering onboard electronics, and can provide enough energy to eliminate the need for batteries in applications such as fuzing. During the munitions firing, a spring-mass system undergoes deformation, thereby storing mechanical potential energy in the elastic element. After release, the spring-mass system is free to vibrate and energy is harvested using piezoelectric materials. Two distinct classes of systems are presented: First are systems where the spring-mass elements are loaded and released directly by the firing acceleration. Second are those which use intermediate mechanisms reacting to the firing acceleration to load and release the spring-mass system. Description and evaluation of various methods for loading and releasing the spring-mass system in the high-impact environment, as well as packaging for very-high-G survivability are discussed at length. Also included are methods for using the devices as hybrid generator-sensors, how the devices intrinsically provide augmented safety, and methods to increase the efficiency of such power sources for very high-G applications. Examples of a number of prototypes for complete high-G energy harvesting systems are presented. These power sources have been designed using extensive modeling, finite element analysis, and model validation testing. The results of laboratory, air-gun and firing tests are also presented.

  8. Hybrid high-energy high-power pulsewidth-tunable picosecond source.

    PubMed

    Pouysegur, Julien; Guichard, Florent; Zaouter, Yoann; Hanna, Marc; Druon, Frédéric; Hönninger, Clemens; Mottay, Eric; Georges, Patrick

    2015-11-15

    A hybrid ytterbium-doped fiber-bulk laser source allowing the generation of 3 ps, 350 μJ, 116 MW peak power Fourier transform-limited pulses at 50 kHz repetition rate and 1030 nm wavelength is described. Pulse duration tunability is provided by an adjustable spectral compression-based seeder system. Energy scaling capabilities of the architecture by use of the divided-pulse amplification method are investigated. This source provides a robust, compact, and versatile solution for applications such as RF photocathode guns, x- and γ-ray generation by inverse Compton scattering, and optical parametric chirped-pulse amplification pumping. PMID:26565830

  9. High Energy Cosmic Electrons: Messengers from Nearby Cosmic Ray Sources or Dark Matter?

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2011-01-01

    This slide presentation reviews the recent discoveries by the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-Ray Telescope in reference to high energy cosmic electrons, and whether their source is cosmic rays or dark matter. Specific interest is devoted to Cosmic Ray electrons anisotropy,

  10. Search for very high energy gamma rays from the galactic plane and other possible galactic sources

    NASA Astrophysics Data System (ADS)

    Morello, C.; Navarra, G.; Periale, L.; Vallania, P.

    An extensive air shower array is operating at the Plateau Rosa station (3.500 m.a.s.l.) since 1980 in the search for very high energy gamma-ray sources. The authors discuss the stability of the array and present the results obtained from Feb. 1982 to Aug. 1985, concerning D.C., periodic and sporadic emissions.

  11. Development of Ultra Small Shock Tube for High Energy Molecular Beam Source

    SciTech Connect

    Miyoshi, Nobuya; Nagata, Shuhei; Kinefuchi, Ikuya; Shimizu, Kazuya; Matsumoto, Yoichiro; Takagi, Shu

    2008-12-31

    A molecular beam source exploiting a small shock tube is described for potential generation of high energy beam in a range of 1-5 eV without any undesirable impurities. The performance of a non-diaphragm type shock tube with an inner diameter of 2 mm was evaluated by measuring the acceleration and attenuation process of shock waves. With this shock tube installed in a molecular beam source, we measured the time-of-flight distributions of shock-heated beams, which demonstrated the ability of controlling the beam energy with the initial pressure ratio of the shock tube.

  12. Development of Ultra Small Shock Tube for High Energy Molecular Beam Source

    NASA Astrophysics Data System (ADS)

    Miyoshi, Nobuya; Nagata, Shuhei; Kinefuchi, Ikuya; Shimizu, Kazuya; Takagi, Shu; Matsumoto, Yoichiro

    2008-12-01

    A molecular beam source exploiting a small shock tube is described for potential generation of high energy beam in a range of 1-5 eV without any undesirable impurities. The performance of a non-diaphragm type shock tube with an inner diameter of 2 mm was evaluated by measuring the acceleration and attenuation process of shock waves. With this shock tube installed in a molecular beam source, we measured the time-of-flight distributions of shock-heated beams, which demonstrated the ability of controlling the beam energy with the initial pressure ratio of the shock tube.

  13. A tunable low-energy photon source for high-resolution angle-resolved photoemission spectroscopy

    SciTech Connect

    Harter, John W.; Monkman, Eric J.; Shai, Daniel E.; Nie Yuefeng; Uchida, Masaki; Burganov, Bulat; Chatterjee, Shouvik; King, Philip D. C.; Shen, Kyle M.

    2012-11-15

    We describe a tunable low-energy photon source consisting of a laser-driven xenon plasma lamp coupled to a Czerny-Turner monochromator. The combined tunability, brightness, and narrow spectral bandwidth make this light source useful in laboratory-based high-resolution photoemission spectroscopy experiments. The source supplies photons with energies up to {approx}7 eV, delivering under typical conditions >10{sup 12} ph/s within a 10 meV spectral bandwidth, which is comparable to helium plasma lamps and many synchrotron beamlines. We first describe the lamp and monochromator system and then characterize its output, with attention to those parameters which are of interest for photoemission experiments. Finally, we present angle-resolved photoemission spectroscopy data using the light source and compare its performance to a conventional helium plasma lamp.

  14. Nonthermal processes around collapsed objects: High energy gamma ray sources in the radio sky

    NASA Technical Reports Server (NTRS)

    Helfand, David J.; Ruderman, Malvin; Applegate, James H.; Becker, Robert H.

    1993-01-01

    In our proposal responding to the initial Guest Observer NRA for the Compton Gamma Ray Observatory, 'Nonthermal Processes Around Collapsed Objects: High Energy Gamma Ray Sources in the Radio Sky', we stated that 'At high energies - the identity of the principal Galactic source population remains unknown' although the 'one certain source of high energy emission is young radio pulsars'. These two statements remain true, although at this writing, eighteen months after the beginning of the Compton allsky survey, much of the gamma-ray data required to greatly extend our knowledge of the Galaxy's high energy emission has been collected. The thrust of the program supported by our grant was to collect and analyze a complementary set of data on the Milky Way at radio wavelengths in order to help identify the dominant Pop 1 component of the Galaxy's gamma ray sources, and to pursue theoretical investigations on the origins and emission mechanisms of young pulsars, the one component of this population identified to date. We summarize here our accomplishments under the grant. In Section 2, we describe our VLA surveys of the Galactic Plane along with the current status of the radio source catalogs derived therefrom; unfortunately, owing to the TDRSS antenna problem and subsequent extension of the Sky Survey, we were not able to carry out a comparison with the EGRET data directly, although everything is now in place to do so as soon as it becomes available. In Section 2, we summarize our progress on the theoretical side, including the substantial completion of a dissertation on pulsar origins and work on the high energy emission mechanisms of isolated pulsars. We list the personnel supported by the grant in section 4 and provide a complete bibliography of publications supported in whole or in part by the grant in the final section.

  15. THE HIGH-ENERGY, ARCMINUTE-SCALE GALACTIC CENTER GAMMA-RAY SOURCE

    SciTech Connect

    Chernyakova, M.; Malyshev, D.; Aharonian, F. A.; Crocker, R. M.; Jones, D. I.

    2011-01-10

    Employing data collected during the first 25 months of observations by the Fermi-LAT, we describe and subsequently seek to model the very high energy (>300 MeV) emission from the central few parsecs of our Galaxy. We analyze the morphological, spectral, and temporal characteristics of the central source, 1FGL J1745.6-2900. The data show a clear, statistically significant signal at energies above 10 GeV, where the Fermi-LAT has angular resolution comparable to that of HESS at TeV energies. This makes a meaningful joint analysis of the data possible. Our analysis of the Fermi data (alone) does not uncover any statistically significant variability of 1FGL J1745.6-2900 at GeV energies on the month timescale. Using the combination of Fermi data on 1FGL J1745.6-2900 and HESS data on the coincident, TeV source HESS J1745-290, we show that the spectrum of the central gamma-ray source is inflected with a relatively steep spectral region matching between the flatter spectrum found at both low and high energies. We model the gamma-ray production in the inner 10 pc of the Galaxy and examine cosmic ray (CR) proton propagation scenarios that reproduce the observed spectrum of the central source. We show that a model that instantiates a transition from diffusive propagation of the CR protons at low energy to almost rectilinear propagation at high energies can explain well the spectral phenomenology. We find considerable degeneracy between different parameter choices which will only be broken with the addition of morphological information that gamma-ray telescopes cannot deliver given current angular resolution limits. We argue that a future analysis performed in combination with higher-resolution radio continuum data holds out the promise of breaking this degeneracy.

  16. Characteristics of High Energy Ka and Bremsstrahlung Sources Generated by Short Pulse Petawatt Lasers

    SciTech Connect

    Park, H; Izumi, N; Key, M H; Koch, J A; Landen, O L; Patel, P K; Phillips, T W; Zhang, B B

    2004-04-13

    We have measured the characteristics of high energy K{alpha} sources created with the Vulcan Petawatt laser at RAL and the JanUSP laser at LLNL. High energy x-ray backlighters will be essential for radiographing High-Energy-Density Experimental Science (HEDES) targets for NIF projects especially to probe implosions and high areal density planar samples. Hard K{alpha} x-ray photons are created through relativistic electron plasma interactions in the target material after irradiation by short pulse high intensity lasers. For our Vulcan experiment, we employed a CsI scintillator/CCD camera for imaging and a CCD camera for single photon counting. We measured the Ag K{alpha} source (22 keV) size using a pinhole array and the K{alpha} flux using a single photon counting method. We also radiographed a high Z target using the high energy broadband x-rays generated from these short pulse lasers. This paper will present results from these experiments.

  17. High homogeneity 25 cm low-energy rf ion source with inherent electron compensation

    NASA Astrophysics Data System (ADS)

    Dudin, S. V.; Rafalskyi, D. V.; Zykov, A. V.

    2010-08-01

    A 25 cm single-grid low-energy rf ion source with inherent electron compensation is described and characterized. Measurements were carried out using Ar and CF4 filling gas. The dependence of the ion beam current to the target as well as the current partition between the beam fast and slow ions on the rf discharge pressure for both filling gases is discussed. The unique ability of generation of coinciding ion and electron flows is demonstrated and the measured ion and electron energy distribution functions are presented as well. The developed broad ion beam source is able of providing 0.5-5 mA/cm2 current density in the low ion energy range of 50-250 eV, with possibility of independent current density and energy control. It is shown that complementing the rf plasma source with a profiling electrode allows for CF4 ion source operation attaining ±5% ion beam uniformity over 250 mm in diameter. The presented CF4 etching test results exhibit the possibility of highly directional anisotropic Si and SiO2 etching utilizing the developed single grid rf ion source.

  18. A New Method for Finding Point Sources in High-energy Neutrino Data

    NASA Astrophysics Data System (ADS)

    Fang, Ke; Miller, M. Coleman

    2016-08-01

    The IceCube collaboration has reported the first detection of high-energy astrophysical neutrinos, including ˜50 high-energy starting events, but no individual sources have been identified. It is therefore important to develop the most sensitive and efficient possible algorithms to identify the point sources of these neutrinos. The most popular current method works by exploring a dense grid of possible directions to individual sources, and identifying the single direction with the maximum probability of having produced multiple detected neutrinos. This method has numerous strengths, but it is computationally intensive and because it focuses on the single best location for a point source, additional point sources are not included in the evidence. We propose a new maximum likelihood method that uses the angular separations between all pairs of neutrinos in the data. Unlike existing autocorrelation methods for this type of analysis, which also use angular separations between neutrino pairs, our method incorporates information about the point-spread function and can identify individual point sources. We find that if the angular resolution is a few degrees or better, then this approach reduces both false positive and false negative errors compared to the current method, and is also more computationally efficient up to, potentially, hundreds of thousands of detected neutrinos.

  19. Dense Plasma Focus - From Alternative Fusion Source to Versatile High Energy Density Plasma Source for Plasma Nanotechnology

    NASA Astrophysics Data System (ADS)

    Rawat, R. S.

    2015-03-01

    The dense plasma focus (DPF), a coaxial plasma gun, utilizes pulsed high current electrical discharge to heat and compress the plasma to very high density and temperature with energy densities in the range of 1-10 × 1010 J/m3. The DPF device has always been in the company of several alternative magnetic fusion devices as it produces intense fusion neutrons. Several experiments conducted on many different DPF devices ranging over several order of storage energy have demonstrated that at higher storage energy the neutron production does not follow I4 scaling laws and deteriorate significantly raising concern about the device's capability and relevance for fusion energy. On the other hand, the high energy density pinch plasma in DPF device makes it a multiple radiation source of ions, electron, soft and hard x-rays, and neutrons, making it useful for several applications in many different fields such as lithography, radiography, imaging, activation analysis, radioisotopes production etc. Being a source of hot dense plasma, strong shockwave, intense energetic beams and radiation, etc, the DPF device, additionally, shows tremendous potential for applications in plasma nanoscience and plasma nanotechnology. In the present paper, the key features of plasma focus device are critically discussed to understand the novelties and opportunities that this device offers in processing and synthesis of nanophase materials using, both, the top-down and bottom-up approach. The results of recent key experimental investigations performed on (i) the processing and modification of bulk target substrates for phase change, surface reconstruction and nanostructurization, (ii) the nanostructurization of PLD grown magnetic thin films, and (iii) direct synthesis of nanostructured (nanowire, nanosheets and nanoflowers) materials using anode target material ablation, ablated plasma and background reactive gas based synthesis and purely gas phase synthesis of various different types of

  20. Are gamma-ray bursts the sources of ultra-high energy cosmic rays?

    NASA Astrophysics Data System (ADS)

    Baerwald, Philipp; Bustamante, Mauricio; Winter, Walter

    2015-03-01

    We reconsider the possibility that gamma-ray bursts (GRBs) are the sources of the ultra-high energy cosmic rays (UHECRs) within the internal shock model, assuming a pure proton composition of the UHECRs. For the first time, we combine the information from gamma-rays, cosmic rays, prompt neutrinos, and cosmogenic neutrinos quantitatively in a joint cosmic ray production and propagation model, and we show that the information on the cosmic energy budget can be obtained as a consequence. In addition to the neutron model, we consider alternative scenarios for the cosmic ray escape from the GRBs, i.e., that cosmic rays can leak from the sources. We find that the dip model, which describes the ankle in UHECR observations by the pair production dip, is strongly disfavored in combination with the internal shock model because (a) unrealistically high baryonic loadings (energy in protons versus energy in electrons/gamma-rays) are needed for the individual GRBs and (b) the prompt neutrino flux easily overshoots the corresponding neutrino bound. On the other hand, GRBs may account for the UHECRs in the ankle transition model if cosmic rays leak out from the source at the highest energies. In that case, we demonstrate that future neutrino observations can efficiently test most of the parameter space - unless the baryonic loading is much larger than previously anticipated.

  1. Hard X-Ray Flare Source Sizes Measured with the Ramaty High Energy Solar Spectroscopic Imager

    NASA Technical Reports Server (NTRS)

    Dennis, Brian R.; Pernak, Rick L.

    2009-01-01

    Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations of 18 double hard X-ray sources seen at energies above 25 keV are analyzed to determine the spatial extent of the most compact structures evident in each case. The following four image reconstruction algorithms were used: Clean, Pixon, and two routines using visibilities maximum entropy and forward fit (VFF). All have been adapted for this study to optimize their ability to provide reliable estimates of the sizes of the more compact sources. The source fluxes, sizes, and morphologies obtained with each method are cross-correlated and the similarities and disagreements are discussed. The full width at half-maximum (FWHM) of the major axes of the sources with assumed elliptical Gaussian shapes are generally well correlated between the four image reconstruction routines and vary between the RHESSI resolution limit of approximately 2" up to approximately 20" with most below 10". The FWHM of the minor axes are generally at or just above the RHESSI limit and hence should be considered as unresolved in most cases. The orientation angles of the elliptical sources are also well correlated. These results suggest that the elongated sources are generally aligned along a flare ribbon with the minor axis perpendicular to the ribbon. This is verified for the one flare in our list with coincident Transition Region and Coronal Explorer (TRACE) images. There is evidence for significant extra flux in many of the flares in addition to the two identified compact sources, thus rendering the VFF assumption of just two Gaussians inadequate. A more realistic approximation in many cases would be of two line sources with unresolved widths. Recommendations are given for optimizing the RHESSI imaging reconstruction process to ensure that the finest possible details of the source morphology become evident and that reliable estimates can be made of the source dimensions.

  2. The Third EGRET Catalog of High-Energy Gamma-Ray Sources

    NASA Technical Reports Server (NTRS)

    Hartman, R. C.; Bertsch, D. L.; Bloom, S. D.; Chen, A. W.; Deines-Jones, P.; Esposito, J. A.; Fichtel, C. E.; Friedlander, D. P.; Hunter, S. D.; McDonald, L. M.; Sreekumar, P.; Thompson, D. J.; Jones, B. B.; Lin, Y. C.; Michelson, P. F.; Nolan, P. L.; Tompkins, W. F.; Kanbach, G.; Mayer-Hasselwander, H. A.; Muecke, A.

    1998-01-01

    The third catalog of high-energy gamma-ray sources detected by the EGRET telescope on the Compton Gamma Ray Observatory includes data from 1991 April 22 to 1995 October 3 (Cycles 1, 2, 3, and 4 of the mission). In addition to including more data than the second EGRET catalog (Thompson et al. 1995) and its supplement (Thompson et al. 1996), this catalog uses completely reprocessed data (to correct a number of mostly minimal errors and problems). The 271 sources (E greater than 100 MeV) in the catalog include the single 1991 solar flare bright enough to be detected as a source, the Large Magellanic Cloud, five pulsars, one probable radio galaxy detection (Cen A), and 66 high-confidence identifications of blazars (BL Lac objects, flat-spectrum radio quasars, or unidentified flat-spectrum radio sources). In addition, 27 lower-confidence potential blazar identifications are noted. Finally, the catalog contains 170 sources not yet identified firmly with known objects, although potential identifications have been suggested for a number of those. A figure is presented that gives approximate upper limits for gamma-ray sources at any point in the sky, as well as information about sources listed in the second catalog and its supplement which do not appear in this catalog.

  3. The Third EGRET Catalog of High-Energy Gamma-Ray Sources

    NASA Technical Reports Server (NTRS)

    Hartman, R. C.; Bertsch, D. L.; Bloom, S. D.; Chen, A. W.; Deines-Jones, P.; Esposito, J. A.; Fichtel, C. E.; Friedlander, D. P.; Hunter, S. D.; McDonald, L. M.; Sreekumar, P.; Thompson, D. J.; Jones, B. B.; Lin, Y. C.; Michelson, P. F.; Nolan, P. L.; Tompkins, W. F.; Kanbach, G.; Mayer-Hasselwander, A.; Muecke, A.

    1998-01-01

    The third catalog of high-energy gamma-ray sources detected by the EGRET telescope on the Compton Gamma Ray Observatory includes data from 1991 April 22 to 1995 October 3 (Cycles 1, 2, 3, and 4 of the mission). In addition to including more data than the second EGRET catalog and its supplement, this catalog uses completely reprocessed data (to correct a number of mostly minimal errors and problems). The 271 sources (E greater than 100 MeV) in the catalog include the single 1991 solar flare bright enough to be detected as a source, the Large Magellanic Cloud, five pulsars, one probable radio galaxy detection (Cen A), and 66 high-confidence identifications of blazars (BL Lac objects, flat-spectrum radio quasars, or unidentified flat-spectrum radio sources). In addition, 27 lower-confidence potential blazar identifications are noted. Finally, the catalog contains 170 sources not yet identified firmly with known objects, although potential identifications have been suggested for a number of those. A figure is presented that gives approximate upper limits for gamma-ray sources at any point in the sky, as well as information about sources listed in the second catalog and its supplement which do not appear in this catalog.

  4. Liquid lithium target as a high intensity, high energy neutron source

    DOEpatents

    Parkin, Don M.; Dudey, Norman D.

    1976-01-01

    This invention provides a target jet for charged particles. In one embodiment the charged particles are high energy deuterons that bombard the target jet to produce high intensity, high energy neutrons. To this end, deuterons in a vacuum container bombard an endlessly circulating, free-falling, sheet-shaped, copiously flowing, liquid lithium jet that gushes by gravity from a rectangular cross-section vent on the inside of the container means to form a moving web in contact with the inside wall of the vacuum container. The neutrons are produced via break-up of the beam in the target by stripping, spallation and compound nuclear reactions in which the projectiles (deuterons) interact with the target (Li) to produce excited nuclei, which then "boil off" or evaporate a neutron.

  5. Search for ultra-high energy emission from Geminga and five unidentified EGRET sources

    SciTech Connect

    Not Available

    1993-01-01

    Data from the CYGNUS extensive air shower array were searched for continuous ultra-high energy (UHE) gamma radiation from five unidentified EGRET sources and from the Geminga pulsar. No evidence for continuous emission from any of these objects was found. Data in the Geminga source bin were also searched for pulsed emission using the recent EGRET ephemeris (237 ms period). No evidence of a periodic signal was found. The 90% confidence level upper limit on the continuous gamma-ray flux above 80 TeV for Geminga is 7.9 [times] 10[sup [minus]14] cm[sup [minus]2] s[sup [minus]1].

  6. Search for ultra-high energy emission from Geminga and five unidentified EGRET sources

    SciTech Connect

    The CYGNUS Collaboration

    1993-05-01

    Data from the CYGNUS extensive air shower array were searched for continuous ultra-high energy (UHE) gamma radiation from five unidentified EGRET sources and from the Geminga pulsar. No evidence for continuous emission from any of these objects was found. Data in the Geminga source bin were also searched for pulsed emission using the recent EGRET ephemeris (237 ms period). No evidence of a periodic signal was found. The 90% confidence level upper limit on the continuous gamma-ray flux above 80 TeV for Geminga is 7.9 {times} 10{sup {minus}14} cm{sup {minus}2} s{sup {minus}1}.

  7. Localization, time histories, and energy spectra of a new type of recurrent high-energy transient source

    NASA Technical Reports Server (NTRS)

    Atteia, J.-L.; Boer, M.; Hurley, K.; Niel, M.; Vedrenne, G.; Fenimore, E. E.; Klebesadel, R. W.; Laros, J. G.; Kuznetsov, A. V.; Kouveliotou, C.

    1987-01-01

    The detection of a recurrent high-energy transient source which is neither a classical X-ray nor a gamma-ray burster, but whose properties are intermediate between the two, is reported. The energy spectra of 12 recurrent events are found to be soft, characterized by kT's of 34-56 keV. The time histories are short with rise and fall times as fast as about 10 ms. The source location is a 0.12 sq deg region about 10 deg from the Galactic center.

  8. High energy X-ray observations of Sco-like sources with Ariel V

    NASA Technical Reports Server (NTRS)

    Greenhill, J. G.; Coe, M. J.; Burnell, S. J. B.; Strong, K. T.; Carpenter, G. F.

    1979-01-01

    Results are reported for observations of Sco X-1 and the similar sources 4U 1702-36 (GX 349+2, Sco X-2), 4U 1813-14 (GX 17+2), and 4U 1758-25 (GX 5-1) by several of the X-ray telescopes aboard the Ariel 5 satellite over the energy range from 2 to approximately 100 keV. The results confirm the existence of a high-energy tail in the spectrum of Sco X-1, demonstrate that 4U 1702-36 has a similar spectrum, and provide evidence for a variation of the 26-56-keV flux from 4U 1702-36 by more than a factor of four with no related change in the 2.9-7.6-keV flux. The high-energy emission from Sco X-1 is found to be one to two orders of magnitude above the extrapolated low-energy emission. Observed X-ray, radio, and optical properties of these four sources, as well as two additional Sco-like sources, are summarized.

  9. High-flux source of low-energy neutral beams using reflection of ions from metals

    NASA Technical Reports Server (NTRS)

    Cuthbertson, John W.; Motley, Robert W.; Langer, William D.

    1992-01-01

    Reflection of low-energy ions from surfaces can be applied as a method of producing high-flux beams of low-energy neutral particles, and is an important effect in several areas of plasma technology, such as in the edge region of fusion devices. We have developed a beam source based on acceleration and reflection of ions from a magnetically confined coaxial RF plasma source. The beam provides a large enough flux to allow the energy distribution of the reflected neutrals to be measured despite the inefficiency of detection, by means of an electrostatic cylindrical mirror analyzer coupled with a quadrupole mass spectrometer. Energy distributions have been measured for oxygen, nitrogen, and inert gas ions incident with from 15 to 70 eV reflected from amorphous metal surfaces of several compositions. For ions of lighter atomic mass than the reflecting metal, reflected beams have peaked energy distributions; beams with the peak at 4-32 eV have been measured. The energy and mass dependences of the energy distributions as well as measurements of absolute flux, and angular distribution and divergence are reported. Applications of the neutral beams produced are described.

  10. High Energy Laboratory Astrophysics Experiments using electron beam ion traps and advanced light sources

    NASA Astrophysics Data System (ADS)

    Brown, Gregory V.; Beiersdorfer, Peter; Bernitt, Sven; Eberle, Sita; Hell, Natalie; Kilbourne, Caroline; Kelley, Rich; Leutenegger, Maurice; Porter, F. Scott; Rudolph, Jan; Steinbrugge, Rene; Traebert, Elmar; Crespo-Lopez-Urritia, Jose R.

    2015-08-01

    We have used the Lawrence Livermore National Laboratory's EBIT-I electron beam ion trap coupled with a NASA/GSFC microcalorimeter spectrometer instrument to systematically address problems found in the analysis of high resolution X-ray spectra from celestial sources, and to benchmark atomic physics codes employed by high resolution spectral modeling packages. Our results include laboratory measurements of transition energies, absolute and relative electron impact excitation cross sections, charge exchange cross sections, and dielectronic recombination resonance strengths. More recently, we have coupled to the Max-Plank Institute for Nuclear Physics-Heidelberg's FLASH-EBIT electron beam ion trap to third and fourth generation advanced light sources to measure photoexcitation and photoionization cross sections, as well as, natural line widths of X-ray transitions in highly charged iron ions. Selected results will be presented.

  11. Axion-Like Particle Imprint in Cosmological Very-High-Energy Sources

    SciTech Connect

    Dominguez, A.; Sanchez-Conde, M.A.; Prada, F.; /IAA, Granada

    2012-06-13

    Discoveries of very high energy (VHE) photons from distant blazars suggest that, after correction by extragalactic background light (EBL) absorption, there is a flatness or even a turn-up in their spectra at the highest energies that cannot be easily explained by the standard framework. Here, it is shown that a possible solution to this problem is achieved by assuming the existence of axion-like particles (ALPs) with masses {approx} 1 neV. The ALP scenario is tested making use of observations of the highest redshift blazars known in the VHE energy regime, namely 3C 279, 3C 66A, PKS 1222+216 and PG 1553+113. In all cases, better fits to the observed spectra are found when including ALPs rather than considering EBL only. Interestingly, quite similar critical energies for photon/ALP conversions are also derived, independently of the source considered.

  12. Some evidence for high energy gamma-ray sources at large galactic latitudes

    NASA Technical Reports Server (NTRS)

    Stamenov, J. N.; Karakula, S.; Tkaczyk, W.

    1985-01-01

    The arrival directions of the gamma-quanta with energies of about 10 to 15th power eV which were registrated by Tien Shan experiment were compared with COS-B observations. On the basis of the Monte Carlo simulations it was shown with low probability that arrival directions of Tien Shan gamma-quanta initiated showers are not uniformly distributed. It is shown that in the region not seen by COS-B mission, the high energy gamma-ray sources should be located at position of 90 deg. 1 sup 11 130 deg and b sup 11 or = 50 deg. The integral intensity of these sources should be I ( 10 to the 15th power eV) = 4.8 + or - 1.7).10 to the 13th power/sq cm/s/str. There is no coincidence between the gamma-quanta registrated by Tien Shan experiment with Geminga intense COS-B gamma source. So it is shown that the integral photon spectrum of Geminga (I(e) approx E sup-Beta, where Beta = 0.8 for E 1 GeV) becomes steeper (Beta 1.2) in high energy region with probability 99.9.%.

  13. High-energy sources at low radio frequency: the Murchison Widefield Array view of Fermi blazars

    NASA Astrophysics Data System (ADS)

    Giroletti, M.; Massaro, F.; D'Abrusco, R.; Lico, R.; Burlon, D.; Hurley-Walker, N.; Johnston-Hollitt, M.; Morgan, J.; Pavlidou, V.; Bell, M.; Bernardi, G.; Bhat, R.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Ewall-Rice, A.; Emrich, D.; Gaensler, B. M.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Hindson, L.; Kaplan, D. L.; Kasper, J. C.; Kratzenberg, E.; Feng, L.; Jacobs, D.; Kudryavtseva, N.; Lenc, E.; Lonsdale, C. J.; Lynch, M. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Offringa, A. R.; Ord, S. M.; Pindor, B.; Prabu, T.; Procopio, P.; Riding, J.; Rogers, A. E. E.; Roshi, A.; Udaya Shankar, N.; Srivani, K. S.; Subrahmanyan, R.; Tingay, S. J.; Waterson, M.; Wayth, R. B.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L.

    2016-04-01

    Context. Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at low radio frequencies. Aims: We characterize the spectral properties of the blazar population at low radio frequency, compare the radio and high-energy properties of the gamma-ray blazar population, and search for radio counterparts of unidentified gamma-ray sources. Methods: We cross-correlated the 6100 deg2 Murchison Widefield Array Commissioning Survey catalogue with the Roma blazar catalogue, the third catalogue of active galactic nuclei detected by Fermi-LAT, and the unidentified members of the entire third catalogue of gamma-ray sources detected by Fermi-LAT. When available, we also added high-frequency radio data from the Australia Telescope 20 GHz catalogue. Results: We find low-frequency counterparts for 186 out of 517 (36%) blazars, 79 out of 174 (45%) gamma-ray blazars, and 8 out of 73 (11%) gamma-ray blazar candidates. The mean low-frequency (120-180 MHz) blazar spectral index is ⟨αlow⟩ = 0.57 ± 0.02: blazar spectra are flatter than the rest of the population of low-frequency sources, but are steeper than at ~GHz frequencies. Low-frequency radio flux density and gamma-ray energy flux display a mildly significant and broadly scattered correlation. Ten unidentified gamma-ray sources have a (probably fortuitous) positional match with low radio frequency sources. Conclusions: Low-frequency radio astronomy provides important information about sources with a flat radio spectrum and high energy. However, the relatively low sensitivity of the present surveys still misses a significant fraction of these objects. Upcoming deeper surveys, such as the GaLactic and Extragalactic All-Sky MWA (GLEAM) survey, will provide further insight into this population. Tables 5-7 are only available at the CDS via anonymous ftp to http

  14. Locating very high energy gamma ray sources with arc minute accuracy

    NASA Technical Reports Server (NTRS)

    Akerlof, C. W.; Cawley, M. F.; Chantell, M.; Fegan, D. J.; Harris, K.; Hillas, A. M.; Jennings, D. G.; Lamb, R. C.; Lawrence, M. A.; Lang, M. J.

    1992-01-01

    The angular accuracy of gamma-ray detectors is intrinsically limited by the physical processes involved in photon detection. Although a number of point-like sources were detected by the COS-B satellite, only two were unambiguously identified by time signature with counterparts at longer wavelengths. By taking advantage of the extended longitudinal structure of Very High Energy gamma-ray showers, measurements in the TeV energy range can pinpoint source coordinates to arc minute accuracy. This was demonstrated using Cerenkov air shower imaging techniques. With two telescopes in coincidence, the individual event circular probable error will be 0.13 deg. The half-cone angle of the field of view is effectively 1 deg.

  15. Radio Monitoring of High Energy Sources by the Green Bank Interferometer

    NASA Astrophysics Data System (ADS)

    Hjellming, Robert

    The environments of accretion disks produce both X-rays and highly- variable radio emission. Satellites like RXTE are providing unprecedented data on the X-ray variability of such sources; the only parallel radio observations, in terms of the number of objects studied, the frequency with which they are observed, and the instantaneous public availability of the data, come from the Green Bank Interferometer (GBI). The high-energy photons observed by RXTE must be related to the high-energy electrons traced by the GBI, and the interpretation of the results from the one instrument is aided immeasurably by the observations of the other. Unfortunately the GBI is now in danger of being shut down due to lack of continuing funding. Here we request such financial support from RXTE.

  16. Galactic PeVatrons: modeling the new sources of high-energy cosmic rays.

    NASA Astrophysics Data System (ADS)

    Gladilin, Petr; Bykov, Andrey; Osipov, Sergey

    Recent observations (experiments Tunka, KASCADE, etc.) indicate that the spectrum of galactic cosmic rays in the energy range of 10(14) - 10(16) eV has notable features (fluctuations) against the background of a general power law. There are breaks in the spectrum and the spectral index varies from 2.93 to 3.21 on them. A possible explanation for this behavior of the spectrum is the imposition of particle spectra from the sources with different spectral indices of accelerated particles. One of these sources could be the systems of two colliding shocks. Such systems can often occur, for example, in active starforming regions near the Galactic Center or in stellar clusters. Special attention is paid to the regions where the shock of the expanding supernova remnant approaches the stellar wind of nearby massive star (or stars). The number of these systems is estimated as 10 systems per Galaxy. Using the non-linear time-dependent model of charged particle acceleration in two shocks colliding system we have shown that these systems have a set of important features and can make a significant contribution to the total flux of galactic cosmic rays in the high energy range 10(12) - 10(16) eV. Numerical calculations showed that the particles accelerated in the system have very hard spectral energy distribution with the index gamma=1. Maximal energies of the proton component accelerated via two-shocks systems extend well above the “knee” and can reach up to 10(15)-10({17)) eV depending on the magnitude of the amplified magnetic field, flows velocities and the system’s size. Hard spectrum of the particles on these energies and high proton intensity (up to 10(36) erg/s) make these sources possibly responsible for the fluctuations in the galactic cosmic rays spectrum.

  17. Dense Plasma Focus With High Energy Helium Beams for Radiological Source Replacement

    NASA Astrophysics Data System (ADS)

    Schmidt, Andrea; Ellsworth, Jennifer; Falabella, Steve; Link, Anthony; Rusnak, Brian; Sears, Jason; Tang, Vincent

    2014-10-01

    A dense plasma focus (DPF) is a compact accelerator that can produce intense high energy ion beams (multiple MeV). It could be used in place of americium-beryllium (AmBe) neutron sources in applications such as oil well logging if optimized to produce high energy helium beams. AmBe sources produce neutrons when 5.5 MeV alphas emitted from the Am interact with the Be. However, due to the very small alpha-Be cross section for alphas <2 MeV, an AmBe source replacement would have to accelerate ~0.15 μC of He to 2 + MeV in order to produce 107 neutrons per pulse. We are using our particle in cell (PIC) model in LSP of a 4 kJ dense plasma focus discharge to guide the optimization of a compact DPF for the production of high-energy helium beam. This model is fluid for the run-down phase, and then transitions to fully kinetic prior to the pinch in order to include kinetic effects such as ion beam formation and anomalous resistivity. An external pulsed-power driver circuit is used at the anode-cathode boundary. Simulations will be benchmarked to He beam measurements using filtered and time-of-flight Faraday cup diagnostics. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work supported by US DOE/NA-22 Office of Non-proliferation Research and Development. Computing support for this work came from the LLNL Institutional Computing Grand Challenge program.

  18. Physical basis for signal separation for remote sensing of multiple high energy radiation sources

    NASA Astrophysics Data System (ADS)

    Richards, J.; Jain, V. K.

    2015-08-01

    In `radiation remote sensing' multiple unknown high energy sources are generally involved. The detectors, upon sensing the corresponding mixed signals, must separate their contributions blindly for further analysis. A practical way to perform this separation could be through the Independent Component Analysis algorithm. However, the challenge faced is that theoretically there is no correlation among events, even those arising from the same source - thereby disabling meaningful ICA analysis. We overcome this hurdle by use of a thin barrier and by providing wide detector pulses. The radiation events that interact with the barrier take a longer time to reach the detector due to their increased path length. They also lose some energy, which makes them increasingly prone to capture in the barrier once they have scattered. These observations are confirmed through Monte-Carlo simulations upon Gamma-ray sources. Normalized crosscovariance up to 0.22 was found, but is actually controllable through appropriate selection of the detector shaping-pulse width. Experiments on a physical setup confirm these findings. Finally, the application of the ICA approach is demonstrated to demix, or separate, the individual contributions of the sources to the observed detector signals.

  19. A New Type of Transient High-Energy Source in the Direction of the Galactic Centre

    NASA Technical Reports Server (NTRS)

    Kouveliotou, C.; VanParadijs, J.; Fishman, G. J.; Briggs, M. S.; Kommers, J.; Harmon, B. A.; Meegan, C. A.; Lewin, W. H. G.

    1996-01-01

    Sources of high-energy (greater than 20 keV) bursts fall into two distinct types: the non-repeating gamma-ray bursters, several thousand of which have been detected but whose origin remains unknown, and the soft gamma-ray repeaters (SGRs), of which there are only three. The SGRs are known to be associated with supernova remnants, suggesting that the burst events most probably originate from young neutron stars. Here we report the detection of a third type of transient high-energy source. On 2 December 1995, we observed the onset of a sequence of hard X-ray bursts from a direction close to that of the Galactic Center. The interval between bursts was initially several minutes, but after two days, the burst rate had dropped to about one per hour and has been largely unchanged since then. More than 1,000 bursts have now been detected, with remarkably similar light curves and intensities; this behaviour is unprecendented among transient X-ray and gamma-ray sources. We suggest that the origin of these bursts might be related to the spasmodic accretion of material onto a neutron star.

  20. On the Evolution of and High-Energy Emission from GHz-Peaked-Spectrum Sources

    SciTech Connect

    Stawarz, L.; Ostorero, L.; Begelman, M.C.; Moderski, R.; Kataoka, J.; Wagner, S.

    2007-12-18

    Here we discuss evolution and broad-band emission of compact (< kpc) lobes in young radio sources. We propose a simple dynamical description for these objects, consisting of a relativistic jet propagating into a uniform gaseous medium in the central parts of an elliptical host. In the framework of the proposed model, we follow the evolution of ultrarelativistic electrons injected from a terminal hotspot of a jet to expanding lobes, taking into account their adiabatic energy losses as well as radiative cooling. This allows us to discuss the broad-band lobe emission of young radio sources. In particular, we argue that the observed spectral turnover in the radio synchrotron spectra of these objects cannot originate from the synchrotron self-absorption process but is most likely due to free-free absorption effects connected with neutral clouds of interstellar medium engulfed by the expanding lobes and photoionized by active centers. We also find a relatively strong and complex high-energy emission component produced by inverse-Compton up-scattering of various surrounding photon fields by the lobes electrons. We argue that such high energy radiation is strong enough to account for several observed properties of GHz-peaked-spectrum (GPS) radio galaxies at UV and X-ray frequencies. In addition, this emission is expected to extend up to GeV (or possibly even TeV) photon energies and can thus be probed by several modern {gamma}-ray instruments. In particular, we suggest that GPS radio galaxies should constitute a relatively numerous class of extragalactic sources detected by GLAST.

  1. Characterization of spatially resolved high resolution x-ray spectrometers for high energy density physics and light source experiments

    SciTech Connect

    Hill, K. W. Bitter, M.; Delgado-Aparacio, L.; Efthimion, P.; Pablant, N. A.; Lu, J.; Beiersdorfer, P.; Chen, H.; Magee, E.

    2014-11-15

    A high resolution 1D imaging x-ray spectrometer concept comprising a spherically bent crystal and a 2D pixelated detector is being optimized for diagnostics of small sources such as high energy density physics (HEDP) and synchrotron radiation or x-ray free electron laser experiments. This instrument is used on tokamak experiments for Doppler measurements of ion temperature and plasma flow velocity profiles. Laboratory measurements demonstrate a resolving power, E/ΔE of order 10 000 and spatial resolution better than 10 μm. Initial tests of the high resolution instrument on HEDP plasmas are being performed.

  2. Automatic Quenching of High Energy gamma-ray Sources by Synchrotron Photons

    SciTech Connect

    Stawarz, Lukasz; Kirk, John; /Heidelberg, Max Planck Inst.

    2007-02-02

    Here we investigate evolution of a magnetized system, in which continuously produced high energy emission undergoes annihilation on a soft photon field, such that the synchrotron radiation of the created electron-positron pairs increases number density of the soft photons. This situation is important in high energy astrophysics, because, for an extremely wide range of magnetic field strengths (nano to mega Gauss), it involves {gamma}-ray photons with energies between 0.3GeV and 30TeV. We derive and analyze the conditions for which the system is unstable to runaway production of soft photons and ultrarelativistic electrons, and for which it can reach a steady state with an optical depth to photon-photon annihilation larger than unity, as well those for which efficient pair loading of the emitting volume takes place. We also discuss the application of our analysis to a realistic situation involving astrophysical sources of a broad-band {gamma}-ray emission and briefly consider the particular case of sources close to active supermassive black holes.

  3. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    NASA Astrophysics Data System (ADS)

    Aloisio, R.; Berezinsky, V.; Blasi, P.

    2014-10-01

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate Xmax(E) and dispersion σ(Xmax) as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must be very hard, ~ E-γ with γ~ 1- 1.6; b) the maximum energy of nuclei of charge Z in the sources must be ~ 5Z× 1018 eV, thereby not requiring acceleration to extremely high energies; c) the fit to the Auger spectrum can be obtained only at the price of adding an ad hoc light extragalactic component with a steep injection spectrum ~ E-2.7). In this sense, at the ankle EA≈ 5× 1018 eV) all the components are of extragalactic origin, thereby suggesting that the transition from Galactic to extragalactic cosmic rays occurs below the ankle. Interestingly, the additional light extragalactic component postulated above compares well, in terms of spectrum and normalization, with the one recently measured by KASCADE-Grande.

  4. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    SciTech Connect

    Aloisio, R.; Blasi, P.

    2014-10-01

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate X{sub max}(E) and dispersion σ(X{sub max}) as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must be very hard, ∼ E{sup -γ} with γ∼ 1- 1.6; b) the maximum energy of nuclei of charge Z in the sources must be ∼ 5Z× 10{sup 18} eV, thereby not requiring acceleration to extremely high energies; c) the fit to the Auger spectrum can be obtained only at the price of adding an ad hoc light extragalactic component with a steep injection spectrum ∼ E{sup -2.7}). In this sense, at the ankle E{sub A}≈ 5× 10{sup 18} eV) all the components are of extragalactic origin, thereby suggesting that the transition from Galactic to extragalactic cosmic rays occurs below the ankle. Interestingly, the additional light extragalactic component postulated above compares well, in terms of spectrum and normalization, with the one recently measured by KASCADE-Grande.

  5. Coded apertures allow high-energy x-ray phase contrast imaging with laboratory sources

    NASA Astrophysics Data System (ADS)

    Ignatyev, K.; Munro, P. R. T.; Chana, D.; Speller, R. D.; Olivo, A.

    2011-07-01

    This work analyzes the performance of the coded-aperture based x-ray phase contrast imaging approach, showing that it can be used at high x-ray energies with acceptable exposure times. Due to limitations in the used source, we show images acquired at tube voltages of up to 100 kVp, however, no intrinsic reason indicates that the method could not be extended to even higher energies. In particular, we show quantitative agreement between the contrast extracted from the experimental x-ray images and the theoretical one, determined by the behavior of the material's refractive index as a function of energy. This proves that all energies in the used spectrum contribute to the image formation, and also that there are no additional factors affecting image contrast as the x-ray energy is increased. We also discuss the method flexibility by displaying and analyzing the first set of images obtained while varying the relative displacement between coded-aperture sets, which leads to image variations to some extent similar to those observed when changing the crystal angle in analyzer-based imaging. Finally, we discuss the method's possible advantages in terms of simplification of the set-up, scalability, reduced exposure times, and complete achromaticity. We believe this would helpful in applications requiring the imaging of highly absorbing samples, e.g., material science and security inspection, and, in the way of example, we demonstrate a possible application in the latter.

  6. SAS-2 observations of high energy gamma rays from discrete sources

    NASA Technical Reports Server (NTRS)

    Kniffen, D. A.; Fichtel, C. E.; Hartman, R. C.; Lamb, R. C.; Thompson, D. J.

    1977-01-01

    The SAS-2 identified six localized high energy (greater than 35 MeV) gamma ray sources. Four of these are the radio pulsars, PSR 0531+21, PSR 0833-45, PSR 1818-04, and PSR 1717-46 discovered in a search of 75 radio pulsars. The fact that only one of these is observed in X-rays, and the significant differences in pulse profiles in the gamma ray and radio observations, leads to the speculation that different mechanisms are involved.

  7. A search for sources of ultra high energy gamma rays at air shower energies with Ooty EAS array

    NASA Technical Reports Server (NTRS)

    Gopalakrishnan, N. V.; Sreekantan, B. V.; Tonwar, S. C.

    1985-01-01

    A 24 detector extensive air shower array is being operated at Ootacamund (2200 m altitude, 11.4 deg N latitude) in southern India to search for sources of Cosmic gamma rays of energies greater then 5 x 10 to the 13th power eV. The angular resolution of the array has been experimentally estimated to be better than about 2 deg. Since June '84, nearly 2.5 million showers have been collected and their arrival directions determined. These showers are being studied to search for very high energy gamma ray emission from interesting astrophysical objects such as Cygnus X-3, Crab pulsar and Geminga.

  8. The development of the high intensity electron cyclotron resonance ion source at China Institute of Atomic Energy.

    PubMed

    Tang, B; Ma, R; Ma, Y; Chen, L; Huang, Q; Liang, H; Cui, B; Jiang, W

    2014-02-01

    High-current microwave ion source has been under development over 15 years for accelerator driven sub-critical system research at China Institute of Atomic Energy, and the beam intensity higher than 140 mA proton beam is produced by this ion source with long lifetime and high reliability. The emittance of high intensity continue-wave and pulse beam is measured on a test-bench in the laboratory. Based on the good performance of this proton ion source, a new 120 mA deuterium ion source is proposed for a high intensity neutron generator. The ion source details and status will be presented. PMID:24593490

  9. First Search for Point Sources of High-energy Cosmic Neutrinos with the ANTARES Neutrino Telescope

    NASA Astrophysics Data System (ADS)

    Adrián-Martínez, S.; Aguilar, J. A.; Samarai, I. Al; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Cârloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, Ph.; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Curtil, C.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhöfer, A.; Ernenwein, J.-P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatà, S.; Gay, P.; Giacomelli, G.; Giordano, V.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lefèvre, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martínez-Mora, J. A.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Palioselitis, D.; Păvălaş, G. E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Richardt, C.; Richter, R.; Rivière, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Salesa, F.; Samtleben, D. F. E.; Sapienza, P.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Seitz, T.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Sánchez-Losa, A.; Taiuti, M.; Tamburini, C.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wagner, S.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.

    2011-12-01

    Results are presented of a search for cosmic sources of high-energy neutrinos with the ANTARES neutrino telescope. The data were collected during 2007 and 2008 using detector configurations containing between 5 and 12 detection lines. The integrated live time of the analyzed data is 304 days. Muon tracks are reconstructed using a likelihood-based algorithm. Studies of the detector timing indicate a median angular resolution of 0.5 ± 0.1 deg. The neutrino flux sensitivity is 7.5 × 10-8(E ν/ GeV)-2 GeV-1 s-1 cm-2 for the part of the sky that is always visible (δ < -48 deg), which is better than limits obtained by previous experiments. No cosmic neutrino sources have been observed. We dedicate this Letter to the memory of our colleague and friend Luciano Moscoso, who passed away during the preparation of this Letter.

  10. ESRF-type lattice design and optimization for the High Energy Photon Source

    NASA Astrophysics Data System (ADS)

    Xu, Gang; Jiao, Yi; Peng, Yue-Mei

    2016-02-01

    A new generation of storage ring-based light sources, called diffraction-limited storage rings (DLSRs), with emittance approaching the diffraction limit for multi-keV photons by means of multi-bend achromat lattices, has attracted extensive studies worldwide. Among various DLSR proposals, the hybrid multi-bend achromat concept developed at the European Synchrotron Radiation Facility (ESRF) predicts an effective way of minimizing the emittance while keeping the required chromatic sextupole strengths to an achievable level. For the High Energy Photon Source planned to be built in Beijing, an ESRF-type lattice design consisting of 48 hybrid seven-bend achromats is proposed to reach emittance as low as 60 pm·rad with a circumference of about 1296 m. Sufficient dynamic aperture, allowing vertical on-axis injection, and moderate momentum acceptance are achieved simultaneously for a promising ring performance. Supported by NSFC (11475202, 11405187) and Youth Innovation Promotion Association CAS (2015009)

  11. Constraining Very High-Energy Gamma Ray Sources Using IceCube Neutrino Observations

    NASA Astrophysics Data System (ADS)

    Vance, Gregory; Feintzeig, J.; Karle, A.; IceCube Collaboration

    2014-01-01

    Modern gamma ray astronomy has revealed the most violent, energetic objects in the known universe, from nearby supernova remnants to distant active galactic nuclei. In an effort to discover more about the fundamental nature of such objects, we present searches for astrophysical neutrinos in coincidence with known gamma ray sources. Searches were conducted using data from IceCube Neutrino Observatory, a cubic-kilometer neutrino detector that is sensitive to astrophysical particles with energies above 1 TeV. The detector is situated at the South Pole, and uses more than 5,000 photomultiplier tubes to detect Cherenkov light from the interactions of particles within the ice. Existing models of proton-proton interactions allow us to link gamma ray fluxes to the production of high-energy neutrinos, so neutrino data from IceCube can be used to constrain the mechanisms by which gamma ray sources create such energetic photons. For a few particularly bright sources, such as the blazar Markarian 421, IceCube is beginning to reach the point where actual constraints can be made. As more years of data are analyzed, the limits will improve and stronger constraints will become possible. This work was supported in part by the National Science Foundation's REU Program through NSF Award AST-1004881 to the University of Wisconsin-Madison.

  12. Galactic sources of high energy neutrinos: Expectation from gamma-ray data

    NASA Astrophysics Data System (ADS)

    Sahakyan, N.

    2016-07-01

    The recent results from ground based γ-ray detectors (HESS, MAGIC, VERITAS) provide a population of TeV galactic γ-ray sources which are potential sources of High Energy (HE) neutrinos. Since the γ-rays and ν-s are produced from decays of neutral and charged pions, the flux of TeV γ-rays can be used to estimate the upper limit of ν flux and vice versa; the detectability of ν flux implies a minimum flux of the accompanying γ-rays (assuming the internal and the external absorption of γ-rays is negligible). Using this minimum flux, it is possible to find the sources which can be detected with cubic-kilometer telescopes. I will discuss the possibility to detect HE neutrinos from powerful galactic accelerators, such as Supernova Remnants (SNRs) and Pulsar Wind Nebulae (PWNe) and show that likely only RX J1713.7-3946, RX J0852.0-4622 and Vela X can be detected by current generation of instruments (IceCube and Km3Net). It will be shown also, that galactic binary systems could be promising sources of HE ν-s. In particular, ν-s and γ-rays from Cygnus X-3 will be discussed during recent gamma-ray activity, showing that in the future such kind of activities could produce detectable flux of HE ν-s.

  13. High-Energy Density science at the Linac Coherent Light Source

    NASA Astrophysics Data System (ADS)

    Glenzer, S. H.; Fletcher, L. B.; Hastings, J. B.

    2016-03-01

    The Matter in Extreme Conditions end station at the Linac Coherent Light Source holds great promise for novel pump-probe experiments to make new discoveries in high- energy density science. In recent experiments we have demonstrated the first spectrally- resolved measurements of plasmons using a seeded 8-keV x-ray laser beam. Forward x-ray Thomson scattering spectra from isochorically heated solid aluminum show a well-resolved plasmon feature that is down-shifted in energy by 19 eV from the incident 8 keV elastic scattering feature. In this spectral range, the simultaneously measured backscatter spectrum shows no spectral features indicating observation of collective plasmon oscillations on a scattering length comparable to the screening length. This technique is a prerequisite for Thomson scattering measurements in compressed matter where the plasmon shift is a sensitive function of the free electron density and where the plasmon intensity provides information on temperature.

  14. HIGH VOLTAGE ION SOURCE

    DOEpatents

    Luce, J.S.

    1960-04-19

    A device is described for providing a source of molecular ions having a large output current and with an accelerated energy of the order of 600 kv. Ions are produced in an ion source which is provided with a water-cooled source grid of metal to effect maximum recombination of atomic ions to molecular ions. A very high accelerating voltage is applied to withdraw and accelerate the molecular ions from the source, and means are provided for dumping the excess electrons at the lowest possible potentials. An accelerating grid is placed adjacent to the source grid and a slotted, grounded accelerating electrode is placed adjacent to the accelerating grid. A potential of about 35 kv is maintained between the source grid and accelerating grid, and a potential of about 600 kv is maintained between the accelerating grid and accelerating electrode. In order to keep at a minimum the large number of oscillating electrons which are created when such high voltages are employed in the vicinity of a strong magnetic field, a plurality of high voltage cascaded shields are employed with a conventional electron dumping system being employed between each shield so as to dump the electrons at the lowest possible potential rather than at 600 kv.

  15. Sources of High-Energy Emission in the Green Pea Galaxies: New Constraints from Magellan Spectra

    NASA Astrophysics Data System (ADS)

    Carroll, Derek Alexander

    2016-01-01

    The recently discovered Green Pea galaxies display extreme starburst activity and may be some of the only possible Lyman continuum emitting galaxies at low redshift. Green Peas are characterized by their unusually high [O III]/[O II] ratios, similar to the ratios observed in high-redshift galaxies. In addition, the presence of the high-energy He II 4686 line shows that the Green Peas are highly ionized. However, the origin of the He II emission in the Green Peas, and many other starburst galaxies, is still an open question. We analyze IMACS and MagE spectra from the Magellan telescopes in order to evaluate the most probable cause of this He II emission. We also analyze other properties like dust content, temperature and density, and kinematic components. Our IMACS spectra show no Wolf-Rayet (WR) features. We set upper limits on the WR populations in our sample and conclude that Wolf-Rayet stars are not a likely candidate for the He II emission. With deeper MagE spectra we investigate energetic shocks as a possible source of the He II, and move one step closer to uncovering the origin of high-energy photons in these unique starbursts.

  16. Mesoscale Science with High Energy X-ray Diffraction Microscopy at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Suter, Robert

    2014-03-01

    Spatially resolved diffraction of monochromatic high energy (> 50 keV) x-rays is used to map microstructural quantities inside of bulk polycrystalline materials. The non-destructive nature of High Energy Diffraction Microscopy (HEDM) measurements allows tracking of responses as samples undergo thermo-mechanical or other treatments. Volumes of the order of a cubic millimeter are probed with micron scale spatial resolution. Data sets allow direct comparisons to computational models of responses that frequently involve long-ranged, multi-grain interactions; such direct comparisons have only become possible with the development of HEDM and other high energy x-ray methods. Near-field measurements map the crystallographic orientation field within and between grains using a computational reconstruction method that simulates the experimental geometry and matches orientations in micron sized volume elements to experimental data containing projected grain images in large numbers of Bragg peaks. Far-field measurements yield elastic strain tensors through indexing schemes that sort observed diffraction peaks into sets associated with individual crystals and detect small radial motions in large numbers of such peaks. Combined measurements, facilitated by a new end station hutch at Advanced Photon Source beamline 1-ID, are mutually beneficial and result in accelerated data reduction. Further, absorption tomography yields density contrast that locates secondary phases, void clusters, and cracks, and tracks sample shape during deformation. A collaboration led by the Air Force Research Laboratory and including the Advanced Photon Source, Lawrence Livermore National Laboratory, Carnegie Mellon University, Petra-III, and Cornell University and CHESS is developing software and hardware for combined measurements. Examples of these capabilities include tracking of grain boundary migrations during thermal annealing, tensile deformation of zirconium, and combined measurements of nickel

  17. The impact of networks of robotic telescopes in continuous monitoring of high energy cosmic sources

    NASA Astrophysics Data System (ADS)

    Giovannelli, Franco; Sabau-Graziati, Lola

    High energy (HE) cosmic sources are characterized by emissions in a wide range of the electromagnetic spectrum. In order to clarify their behavior and understand the involved physics it is necessary to perform simultaneous measurements in a range of energy as wide as possible. This makes it necessary to use different techniques and instrumentation both space- and ground-based. Simultaneous observations are in general very difficult to be performed because they need the involvement of many instruments that belong to many experiments under the control of many groups and countries. However, since the importance of multifrequency measurements is now universally recognized, many efforts are made in order to obtain such measurements. Our group has been a pioneer in such a kind of measurements since middle of 1970s. We will briefly discuss the impact of such measurements in different class of HE cosmic sources, such as T Tauri stars (TTSs), active galactic nuclei (AGNs), gamma-ray bursts (GRBs), X-ray binary systems (XRBs), and cataclysmic variables (CVs). This discussion is mainly based on the review paper "The impact of the space experiments on our knowledge of the physics of the universe" tep{GiovannelliSabauGraziati2004} and subsequent revisions. We will also discuss the importance of having a network of robotic telescopes that can provide long term optical monitoring of the classes of HE sources already discussed. Such measurements will provide fundamental data for understanding many problems that are still open, such as the physics of the outbursts in flaring systems, the search of rotational periods of white dwarfs in CVs and orbital periods of those systems, rotational periods and periodicities of flare-like events of TTSs, correlations between optical and X-ray flares in X-ray/Be systems, fluctuations in the light curves of AGNs and their correlations with the HE emission in order to test the validity of current models, etc.

  18. PEPX-type lattice design and optimization for the High Energy Photon Source

    NASA Astrophysics Data System (ADS)

    Jiao, Yi; Xu, Gang

    2015-06-01

    A new generation of storage ring-based light sources, called diffraction-limited storage rings (DLSR), with emittance approaching the diffraction limit for multi-keV photons by using multi-bend achromat lattice, has attracted worldwide and extensive studies of several laboratories, and been seriously considered as a means of upgrading existing facilities in the imminent future. Among various DLSR proposals, the PEPX design demonstrated that it is feasible to achieve sufficient ring acceptance for off-axis injection in a DLSR, by designing the lattice based on the ‘third-order achromat’ concept and with a special high-beta injection section. For the High Energy Photon Source (HEPS) planned to be built in Beijing, a PEPX-type lattice has been designed and continuously improved. In this paper, we report the evolution of the PEPX-type design for HEPS, and discuss the main issues relevant to the linear optics design and nonlinear optimization. Supported by NSFC (11475202, 11405187) and Youth Innovation Association of Chinese Academy of Sciences (2015009)

  19. Search for ultra high energy gamma-rays from various sources

    NASA Technical Reports Server (NTRS)

    Dzikowski, T.; Gawin, J.; Korejwo, J.; Grochalska, B.; Wdowczyk, J.

    1985-01-01

    The hypothesis that there exists an excess of showers from the Galactic plane on the level 1 to 2% at energies just above 10 to the 16th power eV is explored. The excess shower from the Galactic plane seems to be very similar in properties to excess showers from the point sources/flat spectrum, deficit of low energy muons. Those facts suggest that the excess from the Galactic plane are probably due to summing up of the contribution from individual point sources. That in turn suggest that those sources are rather numerous.

  20. Energy Sources and Development.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with energy sources and development. Its objective is for the student to be able to discuss energy sources and development related to the historical perspective, biological development, current aspects, and future expectations…

  1. Complex carbohydrates as a possible source of high energy to formulate functional feeds.

    PubMed

    Ochoa, Leonel; Paniagua Michel, José de Jesús; Olmos-Soto, Jorge

    2014-01-01

    Carbohydrates (CHOs) are the most abundant organic compounds found in living organisms and are a great source of metabolic energy, both for plants and animals. Besides of CHOs great potential to solve animal's energy requirements and diminishing high feed cost, we first must to understand its digestibility and assimilation to avoid several inconvenients. Today, CHOs feed animal inclusions are of great concern about cost-benefits, animal's health status, and environmental pollution. In this chapter, we make a brief description about sugars (DP1-2), oligosaccharides (DP3-9), polysaccharides (DP ≥10), and their essential characteristics to understand the role of marine and terrestrial CHOs in animal nutrition. Subsequently, we talk about basic concepts, CHOs functional benefits, suggestions about their application and successful cases. This information will contribute to produce a new generation of high-quality and energetic functional feed formulations for livestock and aquaculture farms; which must be of low cost, healthy, and environmentally friendly, with the inclusion of prebiotics and probiotics. PMID:25300550

  2. Two source energy balance model:Refinements and lysimeter tests in the Southern High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A thermal two-source energy balance model (TSM) was evaluated for predicting daily evapotranspiration (ET) of alfalfa, corn, cotton, grain sorghum, soybean, and wheat in a semiarid, advective environment. Crop ET was measured with large, monolythic weighing lysimeters. The TSM solved the energy budg...

  3. Two source energy balance model-refinements and lysimeter tests in the Southern High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A thermal two-source energy balance model (TSM) was evaluated for predicting daily evapotranspiration (ET) of alfalfa, corn, cotton, grain sorghum, soybean, and wheat in a semiarid, advective environment. Crop ET was measured with large, monolythic weighing lysimeters. The TSM solved the energy budg...

  4. On the possibility of observing cosmic ray sources in high energy gamma rays

    NASA Technical Reports Server (NTRS)

    Ormes, J. F.

    1987-01-01

    If cosmic rays are accelerated by strong shocks, then cosmic ray sources should be characterized by spectra, dN/dE alpha E exp -(2.0-2.2), reflecting the strength of those shocks. This is expected from the 'standard leaky box' model of cosmic ray propagation in which the source spectra are harder than the observed spectra because higher energy particles have shorter residence times in the galactic magnetic fields. Furthermore, data on cosmic ray nucleons suggest that these sources might be surrounded by material. If the latter is true, such sources should be observable in gamma rays at energies beyond 1 GeV where the angular resolution of gamma-ray telescopes is optimized and the background is significantly reduced. For identified sources, the source location accuracy can be shown to improve with increasing energy in spite of the decreasing statistics, as long as the gamma-ray spectrum is harder than dN/dE alpha E exp -gamma. A Monte Carlo model is used to predict the photon spectra which would be expected from cosmic ray sources under varying assumptions about the strength of the shocks in the acceleration region.

  5. Z-pinches as intense x-ray sources for high energy density physics application

    SciTech Connect

    Matzen, M.K.

    1997-02-01

    Fast z-pinch implosions can convert more than 10% of the stored electrical energy in a pulsed-power accelerator into x rays. These x rays are produced when an imploding cylindrical plasma, driven by the magnetic field pressure associated with very large axial currents, stagnates upon the cylindrical axis of symmetry. On the Saturn pulsed-power accelerator at Sandia National Laboratories, for example, currents of 6 to 8 MA with a risetime of less than 50 ns are driven through cylindrically-symmetric loads, producing implosions velocities as high as 100 cm/{mu}s and x-ray energies as high as 500 kJ. The keV component of the resulting x-ray spectrum has been used for many years 8 a radiation source for material response studies. Alternatively, the x-ray output can be thermalized into a near-Planckian x-ray source by containing it within a large cylindrical radiation case. These large volume, long-lived radiation sources have recently been used for ICF-relevant ablator physics experiments as well as astrophysical opacity and radiation-material interaction experiments. Hydromagnetic Rayleigh-Taylor instabilities and cylindrical load symmetry are critical, limiting factors in determining the assembled plasma densities and temperatures, and thus in the x-ray pulse widths that can be produced on these accelerators. In recent experiments on the Saturn accelerator, these implosion nonuniformities have been minimized by using uniform-fill gas puff loads or by using wire arrays with as many a 192 wires. These techniques produced significant improvements in the pinched plasma quality, Zn reproducibility, and x-ray output power. X-ray pulse widths of less than 5 ns and peak powers of 75{+-}10 TW have been achieved with arrays of 120 tungsten wires. These powers represent greater than a factor of three in power amplification over the electrical power of the Saturn n accelerator, and are a record for x-ray powers in the laboratory.

  6. Optimizing the operation of a high resolution vertical Johann spectrometer using a high energy fluorescer x-ray source

    SciTech Connect

    Haugh, Michael; Stewart, Richard

    2010-10-15

    This paper describes the operation and testing for a vertical Johann spectrometer (VJS) operating in the 13 keV range. The spectrometer is designed to use thin curved mica crystals or thick germanium crystals. The VJS must have a resolution of E/{Delta}E=3000 or better to measure the Doppler broadening of highly ionized krypton and operate at a small x-ray angle in order to be used as a diagnostic in a laser plasma target chamber. The VJS was aligned, tested, and optimized using a fluorescer type high energy x-ray (HEX) source located at National Security Technologies (NSTec), LLC, in Livermore, CA. The HEX uses a 160 kV x-ray tube to excite fluorescence from various targets. Both rubidium and bismuth fluorescers were used for this effort. This presentation describes the NSTec HEX system and the methods used to optimize and characterize the VJS performance.

  7. High-Energy Density science at the Linac Coherent Light Source

    DOE PAGESBeta

    Glenzer, S. H.; Fletcher, L. B.; Hastings, J. B.

    2016-03-01

    The Matter in Extreme Conditions end station at the Linac Coherent Light Source holds great promise for novel pump-probe experiments to make new discoveries in high- energy density science. Recently, our experiments have demonstrated the first spectrally- resolved measurements of plasmons using a seeded 8-keV x-ray laser beam. Forward x-ray Thomson scattering spectra from isochorically heated solid aluminum show a well-resolved plasmon feature that is down-shifted in energy by 19 eV from the incident 8 keV elastic scattering feature. In this spectral range, the simultaneously measured backscatter spectrum shows no spectral features indicating observation of collective plasmon oscillations on amore » scattering length comparable to the screening length. Moreover, this technique is a prerequisite for Thomson scattering measurements in compressed matter where the plasmon shift is a sensitive function of the free electron density and where the plasmon intensity provides information on temperature.« less

  8. High-Energy Cosmic Ray Self-Confinement Close to Extra-Galactic Sources

    NASA Astrophysics Data System (ADS)

    Blasi, Pasquale; Amato, Elena; D'Angelo, Marta

    2015-09-01

    The ultrahigh-energy cosmic rays observed on the Earth are most likely accelerated in extra-Galactic sources. For the typical luminosities invoked for such sources, the electric current associated to the flux of cosmic rays that leave them is large. The associated plasma instabilities create magnetic fluctuations that can efficiently scatter particles. We argue that this phenomenon forces cosmic rays to be self-confined in the source proximity for energies E sources for energies E source luminosity in units of 1044 erg /s .

  9. High-Energy Cosmic Ray Self-Confinement Close to Extra-Galactic Sources.

    PubMed

    Blasi, Pasquale; Amato, Elena; D'Angelo, Marta

    2015-09-18

    The ultrahigh-energy cosmic rays observed on the Earth are most likely accelerated in extra-Galactic sources. For the typical luminosities invoked for such sources, the electric current associated to the flux of cosmic rays that leave them is large. The associated plasma instabilities create magnetic fluctuations that can efficiently scatter particles. We argue that this phenomenon forces cosmic rays to be self-confined in the source proximity for energies Esources for energies Esource luminosity in units of 10^{44} erg/s. PMID:26430978

  10. Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory

    SciTech Connect

    Collaboration: Pierre Auger Collaboration

    2013-05-01

    We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The density of uniformly distributed sources of equal intrinsic intensity was found to be larger than ∼ (0.06−5) × 10{sup −4} Mpc{sup −3} at 95% CL, depending on the magnitude of the magnetic deflections. Similar bounds, in the range (0.2−7) × 10{sup −4} Mpc{sup −3}, were obtained for sources following the local matter distribution.

  11. Time correlations between low and high energy gamma rays from discrete sources

    NASA Technical Reports Server (NTRS)

    Ellsworth, R. W.

    1995-01-01

    Activities covered the following areas: (1) continuing analysis of the Cygnus Experiment data on the shadowing of cosmic rays by the moon and sun, which led to a direct confirmation of the angular resolution of the CYGNUS EAS array; and (2) development of analysis methods for the daily search overlapping with EGRET targets. To date, no steady emission of ultrahigh energy (UHE) gamma rays from any source has been detected by the Cygnus Experiment, but some evidence for sporadic emission had been found. Upper limits on steady fluxes from 49 sources in the northern hemisphere have been published. In addition, a daily search of 51 possible sources over the interval April 1986 to June 1992 found no evidence for emission. From these source lists, four candidates were selected for comparison with EGRET data.

  12. In-source resonance ionization spectroscopy of high lying energy levels in atomic uranium

    NASA Astrophysics Data System (ADS)

    Raeder, Sebastian; Fies, Silke; Gottwald, Tina; Mattolat, Christoph; Rothe, Sebastian; Wendt, Klaus

    2010-02-01

    In-source resonance ionization spectroscopy of uranium has been carried out as preparation for the analysis of low contaminations of nuclear material in environmental samples via laser mass spectrometry. Using three-step resonance ionization spectroscopy, 86 levels of odd parity in the energy range from 37,200-38,650 cm - 1 were studied, 51 of these levels were previously unknown. Suitable excitation schemes for analytic applications are discussed.

  13. Effect of high energy electrons on H- production and destruction in a high current DC negative ion source for cyclotron

    NASA Astrophysics Data System (ADS)

    Onai, M.; Etoh, H.; Aoki, Y.; Shibata, T.; Mattei, S.; Fujita, S.; Hatayama, A.; Lettry, J.

    2016-02-01

    Recently, a filament driven multi-cusp negative ion source has been developed for proton cyclotrons in medical applications. In this study, numerical modeling of the filament arc-discharge source plasma has been done with kinetic modeling of electrons in the ion source plasmas by the multi-cusp arc-discharge code and zero dimensional rate equations for hydrogen molecules and negative ions. In this paper, main focus is placed on the effects of the arc-discharge power on the electron energy distribution function and the resultant H- production. The modelling results reasonably explains the dependence of the H- extraction current on the arc-discharge power in the experiments.

  14. High brightness electron sources

    SciTech Connect

    Sheffield, R.L.

    1995-07-01

    High energy physics accelerators and free electron lasers put increased demands on the electron beam sources. This paper describes the present research on attaining intense bright electron beams using photoinjectors. Recent results from the experimental programs will be given. The performance advantages and difficulties presently faced by researchers will be discussed, and the following topics will be covered. Progress has been made in photocathode materials, both in lifetime and quantum efficiency. Cesium telluride has demonstrated significantly longer lifetimes than cesium antimonide at 10{sup {minus}8} torr. However, the laser system is more difficult because cesium telluride requires quadrupled YLF instead of the doubled YLF required for cesium antimonide. The difficulty in using photoinjectors is primarily the drive laser, in particular the amplitude stability. Finally, emittance measurements of photoinjector systems can be complicated by the non-thermal nature of the electron beam. An example of the difficulty in measuring beam emittance is given.

  15. A liquid metal ion source in a high energy microprobe setup

    NASA Astrophysics Data System (ADS)

    Adamczewski, J.; Stephan, A.; Meijer, J.; Becker, H. W.; Bukow, H. H.; Rolfs, C.

    1999-10-01

    We describe first experiments with a new arrangement of the Bochum superconducting solenoid microprobe using a single ended electrostatic accelerator and the implementation of a high brightness Ga liquid metal ion source. In this setup the accelerator and the microprobe components are mounted on a common optical bench which is mechanically decoupled from the laboratory building via a separate basement. Care had to be taken of the ion optical adaptation of the source to the accelerator tube in order to preserve the source brightness in the entire experimental setup. The emittance characteristic of the Ga ion beam was determined directly at the location of the microprobe via automatic emittance scanning using the computer controlled slit system of the setup. By this means the parameters of the unfocused beam could be measured for both the accelerated case (315 keV) and the unaccelerated case (30 keV). It could be shown that the observed brightness of the source behind the extraction optics is about three orders of magnitude less than values quoted in the literature (˜10 6 A m -2 rad -2 eV -1) which were deduced from the virtual source size and the angular current density of the ion beam at the source tip. The parameters of the focused beam are presented.

  16. Identification of High Energy Gamma-Ray Sources And Source Populations in the Era of Deep All-Sky Coverage

    SciTech Connect

    Reimer, Olaf; Torres, Diego F.; /ICREA, Barcelona /Barcelona, IEEC

    2007-04-17

    A large fraction of the anticipated source detections by the Gamma-ray Large Area Space Telescope (GLAST-LAT) will initially be unidentified. We argue that traditional approaches to identify individuals and/or populations of gamma ray sources will encounter procedural limitations. Those limitations are discussed on the background of source identifications from EGRET observations. Generally, our ability to classify (faint) source populations in the anticipated GLAST dataset with the required degree of statistical confidence will be hampered by sheer source wealth. A new paradigm for achieving the classification of gamma ray source populations is discussed.

  17. Quightness: A proposed figure of merit for sources of low-energy, high-charge-state ions

    NASA Astrophysics Data System (ADS)

    Schmieder, Robert W.

    1990-03-01

    A variety of ion sources, including the EBIS and ECRIS, are distinguished by their ability to produce low-energy ions of very high charge state. It would be useful to have some figure of merit that is particularly sensitive to this performance. I propose here such a quantity, called ``Quightness,'' which is related to brightness but which enhances the contrast between sources supplying multicharged ions of low energy. The rationale for introducing this quantity, its etymology and relationship to other figures of merit, and some representative values are presented.

  18. High-energy, efficient, 30-Hz ultraviolet laser sources for airborne ozone-lidar systems.

    PubMed

    Elsayed, Khaled A; Chen, Songsheng; Petway, Larry B; Meadows, Byron L; Marsh, Waverly D; Edwards, William C; Barnes, James C; DeYoung, Russell J

    2002-05-20

    Two compact, high-pulse-energy, injection-seeded, 30-Hz frequency-doubled Nd:YAG-laser-pumped Ti: sapphire lasers were developed and operated at infrared wavelengths of 867 and 900 nm. Beams with laser pulse energy >30 mJ at ultraviolet wavelengths of 289 and 300 nm were generated through a tripling of the frequencies of these Ti:sapphire lasers. This work is directed at the replacement of dye lasers for use in an airborne ozone differential absorption lidar system. The ultraviolet pulse energy at 289 and 300 nm had 27% and 31% absolute optical energy conversion efficiencies from input pulse energies at 867 and 900 nm, respectively. PMID:12027160

  19. Locating very high energy gamma-ray sources with arcminute accuracy

    NASA Technical Reports Server (NTRS)

    Akerlof, C. W.; Cawley, M. F.; Chantell, M.; Harris, K.; Lawrence, M. A.; Fegan, D. J.; Lang, M. J.; Hillas, A. M.; Jennings, D. G.; Lamb, R. C.

    1991-01-01

    The angular accuracy of gamma-ray detectors is intrinsically limited by the physical processes involved in photon detection. Although a number of pointlike sources were detected by the COS B satellite, only two have been unambiguously identified by time signature with counterparts at longer wavelengths. By taking advantage of the extended longitudinal structure of VHE gamma-ray showers, measurements in the TeV energy range can pinpoint source coordinates to arcminute accuracy. This has now been demonstrated with new data analysis procedures applied to observations of the Crab Nebula using Cherenkov air shower imaging techniques. With two telescopes in coincidence, the individual event circular probable error will be 0.13 deg. The half-cone angle of the field of view is effectively 1 deg.

  20. A Bright Source of High-Energy X-rays: Final Report on LDRD Project 04-FS-007

    SciTech Connect

    Colvin, J D; Felter, T E; Searson, P C; Chen, M

    2005-02-03

    We have demonstrated the feasibility of fabricating pure-metal foams via a novel four-step technique based upon ion beam lithography. In this report we discuss why and how such foams are useful as bright, high-photon-energy x-ray sources; the details of the fabrication technique we employed to make such foams; the results obtained; and what we plan to do in the future to improve the technique and turn the foams so fabricated into real laser targets for high-brightness, high-energy back lighting.

  1. Counter-facing plasma focus system as a repetitive and/or long-pulse high energy density plasma source

    NASA Astrophysics Data System (ADS)

    Aoyama, Yutaka; Nakajima, Mitsuo; Horioka, Kazuhiko

    2009-11-01

    A plasma focus system composed of a pair of counter-facing coaxial plasma guns is proposed as a long-pulse and/or repetitive high energy density plasma source. A proof-of-concept experiment demonstrated that with an assist of breakdown and outer electrode connections, current sheets evolved into a configuration for stable plasma confinement at the center of the electrodes. The current sheets could successively compress and confine the high energy density plasma every half period of the discharge current, enabling highly repetitive light emissions in extreme ultraviolet region with time durations in at least ten microseconds.

  2. A high resolution gas scintillation proportional counter for studying low energy cosmic X-ray sources

    NASA Technical Reports Server (NTRS)

    Hamilton, T. T.; Hailey, C. J.; Ku, W. H.-M.; Novick, R.

    1980-01-01

    In recent years much effort has been devoted to the development of large area gas scintillation proportional counters (GSPCs) suitable for use in X-ray astronomy. The paper deals with a low-energy GSPC for use in detecting sub-keV X-rays from cosmic sources. This instrument has a measured energy resolution of 85 eV (FWHM) at 149 eV over a sensitive area of 5 sq cm. The development of imaging capability for this instrument is discussed. Tests are performed on the feasibility of using an arrangement of several phototubes placed adjacent to one another to determine event locations in a large flat counter. A simple prototype has been constructed and successfully operated.

  3. [Feasibility of Developing Post High School Technician Programs for Emerging Energy Sources in Southwestern United States.] Policies and Manpower Needs Related to Emerging Energy Sources in Arizona and New Mexico. Final Report.

    ERIC Educational Resources Information Center

    Edington, Everett; And Others

    The energy manpower research project was established to review the process used to identify skills needed in emerging energy sources and to discover any new occupations for which additional post-high school, vocational/technical training would be needed. A supplemental part of the project was the development of a solar energy instructional module.…

  4. Electron beam effective source surface distances for a high energy linear accelerator.

    PubMed

    Sharma, S C; Johnson, M W

    1991-06-01

    The design of the Varian Clinac 1800 linear accelerator electron applicator system does not allow clearance for all head and neck patients to be treated at the standard calibration distance of 100 cm. Discrepancies have been found between dose calculations using the inverse square law for extended distances and their measured data. A 4 X 4 cm2 applicator at an energy of 9 MeV, for example, had dose differences of 13 and 23% at distances of 105 and 110 cm SSD. Because of these discrepancies, effective source surface distances (SSDeff) were determined for all the standard electron energies and applicators of a Clinac 1800. These effective source surface distances ranged from 41.6 cm to 92.6 cm for the 4 X 4 cm2 cone/6 MeV electron beam through the 25 X 25 cm2 cone/20 MeV electron beam. A summary of these distances and an analysis of the clinical use of both a best fit SSDeff and a common SSDeff for patient dosimetry calculations is presented. PMID:1907830

  5. Effect of high energy electrons on H⁻ production and destruction in a high current DC negative ion source for cyclotron.

    PubMed

    Onai, M; Etoh, H; Aoki, Y; Shibata, T; Mattei, S; Fujita, S; Hatayama, A; Lettry, J

    2016-02-01

    Recently, a filament driven multi-cusp negative ion source has been developed for proton cyclotrons in medical applications. In this study, numerical modeling of the filament arc-discharge source plasma has been done with kinetic modeling of electrons in the ion source plasmas by the multi-cusp arc-discharge code and zero dimensional rate equations for hydrogen molecules and negative ions. In this paper, main focus is placed on the effects of the arc-discharge power on the electron energy distribution function and the resultant H(-) production. The modelling results reasonably explains the dependence of the H(-) extraction current on the arc-discharge power in the experiments. PMID:26932009

  6. Measurement of the high energy component of the x-ray spectra in the VENUS electron cyclotron resonance ion source

    SciTech Connect

    Leitner, D.; Benitez, J. Y.; Lyneis, C. M.; Todd, D. S.; Ropponen, T.; Ropponen, J.; Koivisto, H.; Gammino, S.

    2008-03-15

    High performance electron cyclotron resonance (ECR) ion sources, such as VENUS (Versatile ECR for NUclear Science), produce large amounts of x-rays. By studying their energy spectra, conclusions can be drawn about the electron heating process and the electron confinement. In addition, the bremsstrahlung from the plasma chamber is partly absorbed by the cold mass of the superconducting magnet, adding an extra heat load to the cryostat. Germanium or NaI detectors are generally used for x-ray measurements. Due to the high x-ray flux from the source, the experimental setup to measure bremsstrahlung spectra from ECR ion sources is somewhat different from that for the traditional nuclear physics measurements these detectors are generally used for. In particular, the collimation and background shielding can be problematic. In this paper, we will discuss the experimental setup for such a measurement, the energy calibration and background reduction, the shielding of the detector, and collimation of the x-ray flux. We will present x-ray energy spectra and cryostat heating rates depending on various ion source parameters, such as confinement fields, minimum B-field, rf power, and heating frequency.

  7. MEASUREMENT OF THE HIGH ENERGY COMPONENT OF THE X-RAY SPECTRA INTHE VENUS ECR ION SOURCE

    SciTech Connect

    Leitner, Daniela; Benitez, Janilee Y.; Lyneis, Claude M.; Todd,Damon S.; Ropponen,Tommi; Ropponen,Janne; Koivisto, Hannu; Gammino, Santo

    2007-11-15

    High performance electron cyclotron resonance (ECR) ion sources, such as VENUS (Versatile ECR for Nuclear Science), produce large amounts of x-rays. By studying their energy spectra, conclusions can be drawn about the electron heating process and the electron confinement. In addition, the bremsstrahlung from the plasma chamber is partly absorbed by the cold mass of the superconducting magnet adding an extra heat load to the cryostat. Germanium or NaI detectors are generally used for x-ray measurements. Due to the high x-ray flux from the source, the experimental set-up to measure bremsstrahlung spectra from ECR ion sources is somewhat different than for the traditional nuclear physics measurements these detectors are generally used for. In particular the collimation and background shielding can be problematic. In this paper we will discuss the experimental set-up for such a measurement, the energy calibration and background reduction, the correction for detector efficiency, the shielding of the detector and collimation of the x-ray flux. We will present x-ray energy spectra and cryostat heating rates in dependence of various ion source parameters such as confinement fields, minimum B-field, rf power and heating frequency.

  8. High energy neutron radiography

    SciTech Connect

    Gavron, A.; Morley, K.; Morris, C.; Seestrom, S.; Ullmann, J.; Yates, G.; Zumbro, J.

    1996-06-01

    High-energy spallation neutron sources are now being considered in the US and elsewhere as a replacement for neutron beams produced by reactors. High-energy and high intensity neutron beams, produced by unmoderated spallation sources, open potential new vistas of neutron radiography. The authors discuss the basic advantages and disadvantages of high-energy neutron radiography, and consider some experimental results obtained at the Weapons Neutron Research (WNR) facility at Los Alamos.

  9. Development of Compact Electron Cyclotron Resonance Ion Source with Permanent Magnets for High-Energy Carbon-Ion Therapy

    NASA Astrophysics Data System (ADS)

    Muramatsu, M.; Kitagawa, A.; Iwata, Y.; Hojo, S.; Sakamoto, Y.; Sato, S.; Ogawa, Hirotsugu; Yamada, S.; Ogawa, Hiroyuki; Yoshida, Y.; Ueda, T.; Miyazaki, H.; Drentje, A. G.

    2008-11-01

    Heavy-ion cancer treatment is being carried out at the Heavy Ion Medical Accelerator in Chiba (HIMAC) with 140 to 400 MeV/n carbon ions at National Institute of Radiological Sciences (NIRS) since 1994. At NIRS, more than 4,000 patients have been treated, and the clinical efficiency of carbon ion radiotherapy has been demonstrated for many diseases. A more compact accelerator facility for cancer therapy is now being constricted at the Gunma University. In order to reduce the size of the injector (consists of ion source, low-energy beam transport and post-accelerator Linac include these power supply and cooling system), an ion source requires production of highly charged carbon ions, lower electric power for easy installation of the source on a high-voltage platform, long lifetime and easy operation. A compact Electron Cyclotron Resonance Ion Source (ECRIS) with all permanent magnets is one of the best types for this purpose. An ECRIS has advantage for production of highly charged ions. A permanent magnet is suitable for reduce the electric power and cooling system. For this, a 10 GHz compact ECRIS with all permanent magnets (Kei2-source) was developed. The maximum mirror magnetic fields on the beam axis are 0.59 T at the extraction side and 0.87 T at the gas-injection side, while the minimum B strength is 0.25 T. These parameters have been optimized for the production of C4+ based on experience at the 10 GHz NIRS-ECR ion source. The Kei2-source has a diameter of 320 mm and a length of 295 mm. The beam intensity of C4+ was obtained to be 618 eμA under an extraction voltage of 30 kV. Outline of the heavy ion therapy and development of the compact ion source for new facility are described in this paper.

  10. Development of Compact Electron Cyclotron Resonance Ion Source with Permanent Magnets for High-Energy Carbon-Ion Therapy

    SciTech Connect

    Muramatsu, M.; Kitagawa, A.; Iwata, Y.; Hojo, S.; Sakamoto, Y.; Sato, S.; Ogawa, Hirotsugu; Yamada, S.; Ogawa, Hiroyuki; Yoshida, Y.; Ueda, T.; Miyazaki, H.; Drentje, A. G.

    2008-11-03

    Heavy-ion cancer treatment is being carried out at the Heavy Ion Medical Accelerator in Chiba (HIMAC) with 140 to 400 MeV/n carbon ions at National Institute of Radiological Sciences (NIRS) since 1994. At NIRS, more than 4,000 patients have been treated, and the clinical efficiency of carbon ion radiotherapy has been demonstrated for many diseases. A more compact accelerator facility for cancer therapy is now being constricted at the Gunma University. In order to reduce the size of the injector (consists of ion source, low-energy beam transport and post-accelerator Linac include these power supply and cooling system), an ion source requires production of highly charged carbon ions, lower electric power for easy installation of the source on a high-voltage platform, long lifetime and easy operation. A compact Electron Cyclotron Resonance Ion Source (ECRIS) with all permanent magnets is one of the best types for this purpose. An ECRIS has advantage for production of highly charged ions. A permanent magnet is suitable for reduce the electric power and cooling system. For this, a 10 GHz compact ECRIS with all permanent magnets (Kei2-source) was developed. The maximum mirror magnetic fields on the beam axis are 0.59 T at the extraction side and 0.87 T at the gas-injection side, while the minimum B strength is 0.25 T. These parameters have been optimized for the production of C{sup 4+} based on experience at the 10 GHz NIRS-ECR ion source. The Kei2-source has a diameter of 320 mm and a length of 295 mm. The beam intensity of C{sup 4+} was obtained to be 618 e{mu}A under an extraction voltage of 30 kV. Outline of the heavy ion therapy and development of the compact ion source for new facility are described in this paper.

  11. Embedded star clusters as sources of high-energy cosmic rays . Modelling and constraints

    NASA Astrophysics Data System (ADS)

    Maurin, G.; Marcowith, A.; Komin, N.; Krayzel, F.; Lamanna, G.

    2016-06-01

    Context. Massive stars are mainly found in stellar associations. These massive star clusters occur in the heart of giant molecular clouds. The strong stellar wind activity in these objects generates large bubbles and induces collective effects that could accelerate particles up to high energy and produce γ-rays. The best way to input an acceleration origin to the stellar wind interaction in massive stellar cluster is to observe young massive star clusters in which no supernova explosion has occurred yet. Aims: This work aims to constrain the part of stellar wind mechanical energy that is converted into energetic particles using the sensitivity of the ongoing Fermi-LAT instrument. This work further provides detailed predictions of expected γ-ray fluxes in the view of the on-set of the next generation of imaging atmospheric Cherenkov telescopes. Methods: A one-zone model where energetic particles are accelerated by repeated interactions with strong supersonic shocks occurring in massive star clusters was developed. The particle escape from the star cluster and subsequent interaction with the surrounding dense material and magnetic fields of the HII region was computed. We applied this model to a selection of eight embedded star clusters constricted by existing observations. We evaluated the γ-ray signal from each object, combining both leptonic and hadronic contributions. We searched for these emissions in the Fermi-LAT observations in the energy range from 3 to 300 GeV and compared them to the sensitivity of the Cherenkov Telescope Array (CTA). Results: No significant γ-ray emission from these star clusters has been found. Less than 10% of stellar wind luminosities are supplied to the relativistic particles. Some clusters even show acceleration efficiency of less than 1%. The CTA would be able to detect γ-ray emission from several clusters in the case of an acceleration efficiency of close to one percent.

  12. High energy metal ion implantation using `Magis`, a novel, broad-beam, Marx-generator-based ion source

    SciTech Connect

    Anders, A.; Brown, I.G.; Dickinson, M.R.; MacGill, R.A.

    1996-08-01

    Ion energy of the beam formed by an ion source is proportional to extractor voltage and ion charge state. Increasing the voltage is difficult and costly for extraction voltage over 100 kV. Here we explore the possibility of increasing the charge states of metal ions to facilitate high-energy, broad beam ion implantation at a moderate voltage level. Strategies to enhance the ion charge state include operating in the regimes of high-current vacuum sparks and short pulses. Using a time-of-flight technique we have measured charge states as high as 7+ (73 kA vacuum spark discharge) and 4+ (14 kA short pulse arc discharge), both for copper, with the mean ion charge states about 6.0 and 2.5, respectively. Pulsed discharges can conveniently be driven by a modified Marx generator, allowing operation of ``Magis`` with a single power supply (at ground potential) for both plasma production and ion extraction.

  13. Applying high frame-rate digital radiography and dual-energy distributed-sources for advanced tomosynthesis

    NASA Astrophysics Data System (ADS)

    Travish, Gil; Rangel, Felix J.; Evans, Mark A.; Schmiedehausen, Kristin

    2013-09-01

    Conventional radiography uses a single point x-ray source with a fan or cone beam to visualize various areas of the human body. An imager records the transmitted photons—historically film and now increasingly digital radiography (DR) flat panel detectors—followed by optional image post-processing. Some post-processing techniques of particular interest are tomosynthesis, and dual energy subtraction. Tomosynthesis adds the ability to recreate quasi-3D images from a series of 2D projections. These exposures are typically taken along an arc or other path; and, tomosynthesis reconstruction is used to form a three-dimensional representation of the area of interest. Dual-energy radiography adds the ability to enhance or "eliminate" structures based on their different attenuation of well-separated end-point energies in two exposures. These advanced capabilities come at a high cost in terms of complexity, imaging time, capital equipment, space, and potentially reduced image quality due to motion blur if acquired sequentially. Recently, the prospect of creating x-ray sources, which are composed of arrays of micro-emitters, has been put forward. These arrays offer a flat-panel geometry and may afford advantages in fabrication methodology, size and cost. They also facilitate the use of the dual energy technology. Here we examine the possibility of using such an array of x-ray sources combined with high frame-rate (~kHz) DR detectors to produce advanced medical images without the need for moving gantries or other complex motion systems. Combining the advantages of dual energy imaging with the ability to determine the relative depth location of anatomical structures or pathological findings from imaging procedures should prove to be a powerful diagnostic tool. We also present use cases that would benefit from the capabilities of this modality.

  14. On the high-energy gamma-ray signature of cosmic-ray sources

    NASA Technical Reports Server (NTRS)

    Ormes, J. F.; Ozel, M. E.; Morris, D. J.

    1988-01-01

    Monte Carlo simulations of the gamma-ray emission from hypothetical cosmic-ray sources are performed. Sources which might correspond to acceleration by supernova shocks in 'average' interstellar conditions and deep within giant molecular clouds are considered. The consequences of dropping the common assumption that the cosmic-ray spectrum at the sources is the same as that observed at earth are examined. Spectral effects which can be related to the depth of the material shroud and the population of accelerated particles are explored using these simulations and are described. The results are compared with the COS B catalog of gamma-ray sources, and the implications for the underlying particle populations and source mechanisms are discussed.

  15. The long-term Swift observations of the high-energy peaked BL Lacertae source 1ES 1959+650

    NASA Astrophysics Data System (ADS)

    Kapanadze, B.; Romano, P.; Vercellone, S.; Kapanadze, S.; Mdzinarishvili, T.; Kharshiladze, G.

    2016-03-01

    We present the results based on the monitoring of the high-energy peaked BL Lacertae object 1ES 1959+650 by the Swift satellite during 2005-2014. Our timing study shows that the source was highly variable on longer (weeks-to-months) time-scales with the 0.3-10 keV fluxes ranging by a factor of 8. It sometimes showed a significant intra-day variability in the course of ˜1 ks, detected mainly in the epochs of higher brightness states. The flux variability exhibited an erratic character and no signatures of periodic variations are revealed. The X-ray spectra were mainly curved with broad ranges of photon index, curvature parameter, hardness ratio, synchrotron spectral energy distribution (SED) peak location which exhibited a significant variability with the flux at different time-scales. Our study of multi-wavelength cross-correlations shows that the one-zone synchrotron self-Compton scenario was not always valid for 1ES 1959+650. The X-ray flares were sometimes not accompanied with an increasing activity in the γ-ray or lower-energy parts of the spectrum and vice versa. Similar to the prominent `orphan' TeV event in 2002, significant flares in the high-energy and very high energy bands in 2009 May and 2012 May were not accompanied by those in the synchrotron part of the spectrum. Similar to other TeV-detected high-energy peaked BLLs, the stochastic acceleration of the electrons from the magnetic turbulence close to the shock front may be more important for our target compared to other scenarios since it showed mainly broader synchrotron SEDs during the X-ray flares expected when the stochastic mechanism is more efficient.

  16. The effect of high energy concentration source irradiation on structure and properties of Fe-based bulk metallic glass

    NASA Astrophysics Data System (ADS)

    Pilarczyk, Wirginia

    2016-06-01

    Metallic glasses exhibit metastable structure and maintain this relatively stable amorphous state within certain temperature range. High intensity laser beam was used for the surface irradiation of Fe-Co-B-Si-Nb bulk metallic glasses. The variable parameter was laser beam pulse energy. For the analysis of structure and properties of bulk metallic glasses and their surface after laser remelting the X-ray analysis, microscopic observation and test of mechanical properties were carried out. Examination of the nanostructure of amorphous materials obtained by high pressure copper mold casting method and the irradiated with the use of TITAN 80-300 HRTEM was carried out. Nanohardness and reduced Young's modulus of particular amorphous and amorphous-crystalline material zone of the laser beam were examined with the use of Hysitron TI950 Triboindenter nanoindenter and with the use of Berkovich's indenter. The XRD and microscopic analysis showed that the test material is amorphous in its structure before irradiation. Microstructure observation with electron transmission microscopy gave information about alloy crystallization in the irradiated process. Identification of given crystal phases allows to determine the kind of crystal phases created in the first place and also further changes of phase composition of alloy. The main value of the nanohardness of the surface prepared by laser beam has the order of magnitude similar to bulk metallic glasses formed by casting process irrespective of the laser beam energy used. Research results analysis showed that the area between parent material and fusion zone is characterized by extraordinarily interesting structure which is and will be the subject of further analysis in the scope of bulk metallic glasses amorphous structure and high energy concentration source. The main goal of this work is the results' presentation of structure and chosen properties of the selected bulk metallic glasses after casting process and after irradiation

  17. High-Brightness Beam Generation and Characterization at the Advanced Photon Source Low-Energy Undulator Test Line Linac*

    NASA Astrophysics Data System (ADS)

    Lewellen, John; Biedron, Sandra; Borland, Michael; Hahne, Michael; Harkay, Katherine; Lumpkin, Alex; Milton, Stephen; Sereno, Nicholas; Travish, Gil

    2000-04-01

    Improvements to the Advanced Photon Source injector linac have been made to allow for the production and characterization of high-brightness beams in support of fourth-generation light source research. In particular, effort has been directed at generating beams suitable for use in the low-energy undulator test line (LEUTL) free-electron laser (FEL). We describe the enhancements to the linac operational and diagnostic capabilities that enabled self-amplified spontaneous emission (SASE) operation of the FEL at 530 nm. Electron beam measurement techniques and recent results will be discussed. Beam properties are measured under the same operational conditions as those used for FEL studies. The nominal FEL beam parameters are as follows: 217 MeV beam energy; less than 0.15 mm-mrad normalized emittance; 100 A peak current from a 0.7-nC charge at a 7-psec bunch. * Work supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. W-31-109-ENG-38

  18. Tentative study on high-photon-energy quasi-x-ray laser generator by forming plasma x-ray source

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Hayasi, Yasuomi; Ichimaru, Toshio; Mori, Hidezo; Tanaka, Etsuro; Ojima, Hidenori; Takayama, Kazuyoshi; Usuki, Tatsumi; Sato, Koetsu; Sakamaki, Kimio; Tamakawa, Yoshiharu

    2001-04-01

    Tentative study on high-photon-energy quasi-x-ray-laser generator by forming plasma x-ray source is described. The generator employs a high-voltage power supply, a low-impedance coaxial transmission line, a high-voltage condenser with a capacity of about 200 nF, a turbo-molecular pump, a thyristor pulse generator as a trigger device, and a flash x-ray tube. The high-voltage main condenser is charged up to 60 kV by the power supply, and the electric charges in the condenser are discharged to the tube after triggering the cathode electrode. The flash x-rays are then produced. The x-ray tube is of a demountable triode that is connected to the turbo molecular pump with a pressure of approximately 1 mPa. As the electron flows from the cathode electrode are roughly converged to the copper target by the electric field in the tube, the plasma x- ray source, which consists of metal ions and electrons, forms by the target evaporating. Both the tube voltage and current displayed damped oscillations, and their peak values increased according to increases in the charging voltage. In the present work, the peak tube voltage was much higher than the initial charging voltage of the main condenser, and the peak current was about 25 kA with a charging voltage of 60 kV. When the charging voltage was increased, the plasma x-ray source formed, and the characteristic x-ray intensities of K-series lines increased. When the plate target was employed, we observed high-intensity characteristic x-rays from the axial direction of the linear plasma x-ray source. In the case where the rod target was employed, we detected higher-intensity characteristic x-rays.

  19. Compact high-power/high-energy 2 μm and mid-infrared laser sources for OCM

    NASA Astrophysics Data System (ADS)

    Kieleck, C.; Hildenbrand, A.; Schellhorn, M.; Stoeppler, G.; Eichhorn, M.

    2013-10-01

    The paper describes two laser prototypes devoted to the jamming or the damaging of heat-seeking missiles for use in field trials. The semi-ruggedized compact jamming prototype is based either on an OP-GaAs or a ZnGeP2 (ZGP) OPO directly pumped by a 2.09 μm Q-switched Ho3+:YAG laser with up to 20 W of average power around 2.1 μm and an M2 of less than 1.1. For jamming in band II, up to 3.5 W of average power were obtained and repetition rates from 20 kHz to 100 kHz were achieved. For 3.5 W of averaged output power, the M2 of the signal and idler beams were estimated to be less than 1.2. The destruction laser consists of a Ho3+:LLF MOPA laser system which is used to pump a ZGP OPO. The maximum pulse energy of the Ho3+:LLF MOPA was 82 mJ at a repetition rate of 100 Hz. The pump beam quality was measured to M2x = 1.01 and M2y = 1.03 at a wavelength of 2053 nm. The total 3-5 μm energy obtained for destruction was 23.4 mJ, corresponding to an optical-to-optical conversion efficiency of 51 %. The M2 values of the signal were M2x = 1.81 and M2y = 1.98. The M2 values of the corresponding idler beam were M2x = 1.91 and M2y = 1.94, respectively. ISL is also currently working on new laser sources and non linear conversion setups for proposing new versions that should be more compact, more efficient and more integrable.

  20. Advances in the Two Source Energy Balance (TSEB) model using very high resolution remote sensing data in vineyards

    NASA Astrophysics Data System (ADS)

    Nieto Solana, H.; Kustas, W. P.; Torres-Rua, A. F.; ELarab, M.; Song, L.; Alfieri, J. G.; Prueger, J. H.; McKee, L.; Anderson, M. C.; Alsina, M. M.; Jensen, A.; McKee, M.

    2015-12-01

    The thermal-based Two Source Energy Balance (TSEB) model partitions the water and energy fluxes from vegetation and soil components providing thus the ability for estimating soil evaporation (E) and canopy transpiration (T) separately. However, it is crucial for ET partitioning to retrieve reliable estimates of canopy and soil temperatures as well as the net radiation partitioning (ΔRn), as the latter determines the available energy for water and heat exchange from soil and canopy sources. These two factors become especially relevant in agricultural areas, with vegetation clumped along rows and hence only partially covering the soil surface for much of the growing season. The effects on radiation and temperature partitioning is extreme for vineyards and orchards, where there is often significant separation between plants, resulting in strongly clumped vegetation with significant fraction of bare soil/substrate. To better understand the effects of strongly clumped vegetation on radiation and Land Surface Temperature (LST) partitioning very high spatial resolution remote sensing data acquired from an Unmanned Aerial System (UAS) were collected over vineyards in Califronia, as part of the Grape Remote sensing and Atmospheric Profile and Evapotranspiration eXperiment (GRAPEX).The multi-temporal observations from the UAS and very high pixel resolution permitted the estimation of reliable soil and leaf temperatures using a contextual algorithm based on the inverse relationship between LST and a vegetation index. An improvement in the algorithm estimating the effective leaf area index explicitly developed for vine rows and ΔRn using the 4SAIL Radiative Transfer Model is as well developed. The revisions to the TSEB model are evaluated with in situ measurements of energy fluxes and transmitted solar radiation. Results show that the modifications to the TSEB resulted in closer agreement with the flux tower measurements compared to the original TSEB model formulations. The

  1. Potential of renewable and alternative energy sources

    NASA Astrophysics Data System (ADS)

    Konovalov, V.; Pogharnitskaya, O.; Rostovshchikova, A.; Matveenko, I.

    2015-11-01

    The article deals with application potential of clean alternative renewable energy sources. By means of system analysis the forecast for consumption of electrical energy in Tomsk Oblast as well as main energy sources of existing energy system have been studied up to 2018. Engineering potential of renewable and alternative energy sources is evaluated. Besides, ranking in the order of their efficiency descending is performed. It is concluded that Tomsk Oblast has high potential of alternative and renewable energy sources, among which the most promising development perspective is implementation of gasification stations to save fuel consumed by diesel power stations as well as building wind-power plants.

  2. Non-conventional energy sources

    SciTech Connect

    Furlan, G.; Rodriguez, H.; Violini, G.

    1982-01-01

    This book presents the papers given at a conference on renewable energy sources. Topics considered at the conference included the estimate of global and diffuse radiation, thin films in photothermal solar energy conversion, solar collectors, prospects for photovoltaic products in the developing countries, passive energy systems in buildings, hydrogen fuels, geothermal energy, wind energy, tidal energy, and wave energy in developing countries.

  3. Talbot-Lau based Moiré deflectometry with non-coherent sources as potential High Energy Density plasma diagnostic

    NASA Astrophysics Data System (ADS)

    Valdivia, M. P.; Stutman, D.; Finkenthal, M.

    2013-10-01

    X-ray phase-contrast radiography could better characterize highly localized density gradients expected in High Energy Density (HED) plasma experiments than conventional attenuation radiography. In particular, the Talbot-Lau (TL) grating interferometer, which works with extended and polychromatic x-ray sources, is a potentially attractive HED diagnostic due to its high sensitivity. For HED characterization the TL setup and imaging techniques must be changed from the recently studied medical system. The object magnification must be increased greatly in order to resolve μm scale gradients while the Talbot magnification must be increased in order to keep the gratings away from the plasma. Additionally, techniques for retrieving the density profile from a single plasma image must be developed. We thus study the performance of high magnification TL interferometers, in conjunction with Moiré fringe deflectometry for single image phase retrieval. The results show a very good interferometer contrast (≤30%) at high magnification. The Moiré technique enables measuring both sharp and mild density gradients with good accuracy and spatial resolution. Both the laboratory and simulation studies indicate that the TL based Moiré deflectometry is more sensitive than the propagation phase-contrast method when utilizing an extended x-ray source (˜80 μm). In HED experiments this would allow for less demanding X-ray backlighters than those used at present.

  4. Talbot-Lau based Moiré deflectometry with non-coherent sources as potential High Energy Density plasma diagnostic

    SciTech Connect

    Valdivia, M. P.; Stutman, D.; Finkenthal, M.

    2013-10-28

    X-ray phase-contrast radiography could better characterize highly localized density gradients expected in High Energy Density (HED) plasma experiments than conventional attenuation radiography. In particular, the Talbot-Lau (TL) grating interferometer, which works with extended and polychromatic x-ray sources, is a potentially attractive HED diagnostic due to its high sensitivity. For HED characterization the TL setup and imaging techniques must be changed from the recently studied medical system. The object magnification must be increased greatly in order to resolve μm scale gradients while the Talbot magnification must be increased in order to keep the gratings away from the plasma. Additionally, techniques for retrieving the density profile from a single plasma image must be developed. We thus study the performance of high magnification TL interferometers, in conjunction with Moiré fringe deflectometry for single image phase retrieval. The results show a very good interferometer contrast (≤30%) at high magnification. The Moiré technique enables measuring both sharp and mild density gradients with good accuracy and spatial resolution. Both the laboratory and simulation studies indicate that the TL based Moiré deflectometry is more sensitive than the propagation phase-contrast method when utilizing an extended x-ray source (∼80 μm). In HED experiments this would allow for less demanding X-ray backlighters than those used at present.

  5. Modeling surface energy fluxes over Texas High Plains using Two-Source Model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evapotranspiration (ET) is an essential component of the water balance and a major consumptive use of irrigation water and precipitation on cropland. In this study, we applied the Two-Source Model (TSM) to estimate hourly and daily ET from the Landsat Thematic Mapper (TM) data for the semi-arid Texa...

  6. Exploring the nature of the unidentified very-high-energy gamma-ray source HESS J1507-622

    NASA Astrophysics Data System (ADS)

    Domainko, W.; Ohm, S.

    2012-09-01

    Context. Several extended sources of very-high-energy (VHE; E > 100 GeV) gamma rays have been found that lack counterparts belonging to an established class of VHE gamma-ray emitters. Aims: The nature of the first unidentified VHE gamma-ray source with significant angular offset from the Galactic plane of 3.5°, HESS J1507-622, is explored. Methods.Fermi-LAT data in the high-energy (HE, 100 MeV < E < 100 GeV) gamma-ray range collected over 34 month are used to describe the spectral energy distribution (SED) of the source. Additionally, implications of the off-plane location of the source for a leptonic and hadronic gamma-ray emission model are investigated. Results: HESS J1507-622 is detected in the Fermi energy range and its spectrum is best described by a power law in energy with Γ = 1.7 ± 0.1stat ± 0.2sys and integral flux between (0.3-300) GeV of F = (2.0 ± 0.5stat ± 1.0sys) × 10-9 cm-2 s-1. The SED constructed from the Fermi and H.E.S.S. data for this source does not support a smooth power-law continuation from the VHE to the HE gamma-ray range. With the available data it is not possible to discriminate between a hadronic and a leptonic scenario for HESS J1507-622. The location and compactness of the source indicate a considerable physical offset from the Galactic plane for this object. In case of a multiple-kpc distance, this challenges a pulsar wind nebula (PWN) origin for HESS J1507-622 since the time of travel for a pulsar born in the Galactic disk to reach such a location would exceed the inverse Compton (IC) cooling time of electrons that are energetic enough to produce VHE gamma-rays. However, an origin of this gamma-ray source connected to a pulsar that was born off the Galactic plane in the explosion of a hypervelocity star cannot be excluded. Conclusions: The nature of HESS J1507-622 is still unknown to date, and a PWN scenario cannot be ruled out in general. On the contrary HESS J1507-622 could be the first discovered representative of a

  7. Systematic search for molecular clouds near supernova remnants as sources of very-high-energy γ-ray emission

    NASA Astrophysics Data System (ADS)

    Häffner, Stephanie; Stegmann, Christian; Jung-Richardt, Ira

    2015-12-01

    Supernova remnants accelerate particles up to energies of at least 100 TeV as established by observations in very-high-energy γ-ray astronomy. Molecular clouds in their vicinity provide an increased amount of target material for proton-proton interaction and subsequent neutral pion decay into γ-rays of accelerated hadrons escaping the remnant. Therefore, these molecular clouds are potential γ-ray sources. The γ-ray emission from these clouds provides a unique environment to derive information on the propagation of very-high-energy particles through the interstellar medium as well as on the acceleration of hadrons in supernova remnants. Current Imaging Atmospheric Cherenkov Telescope systems are suitable to explore a large parameter space of the propagation properties depending on the age of the supernova remnant and the distance between the remnant and the nearby molecular cloud. In this paper we present our strategy and results of a systematic search for γ-ray emitting molecular clouds near supernova remnants which are potentially detectable with current experiments in the TeV energy range and explore the prospects of future experiments.

  8. Energy sources for Nigeria

    SciTech Connect

    Okoroji, C.E.I.

    1982-09-01

    A public consensus has developed on the need for national energy policies and better planning in the utilization of energy resources in Nigeria. A look at Nigeria's energy future is timely as a period of rapid technological growth and industrial development begins. At the present time, Nigeria exports a relatively high percentage (92%) of the petroleum produced annually. In addition, about 95% of all produced natural gas is flared. Only a relatively minor fraction of the coal produced is used and the rest exported to West African countries. Water power in Nigeria is not yet fully developed. Although the deposits of uranium and oil sand may be substantial, the reserves are not currently known. The proportions in which mineral fuels are used are not related to their relative abundance. Based on present production rates, domestic reserves of petroleum will last 20 years, those of natural gas 63 years, and those of coal 1503 years. Nigeria is not currently and is not likely to become self-sufficient in terms of energy requirements. During the past decade, Nigeria's population has increased by 28.4%. Of vital concern for the immediate future in Nigeria are the demands on energy consumption and mineral resources resulting from increasing population pressure.

  9. Development of A Semiconductor Laser Based High Temperature Fine Thermal Energy Source in an Optical Fiber Tip for Clinical Applications

    NASA Astrophysics Data System (ADS)

    Fujimoto, Takahiro; Imai, Yusuke; Tei, Kazuyoku; Yamaguchi, Shigeru

    2013-05-01

    A new technique for generating high temperatures on the surface of an optical fiber is developed for medical applications using lower-power semiconductor lasers with output powers lower than 10 W. Using a power level of 4-6 W semiconductor laser with a pulse duration of 180 ms at a wavelength of 980 nm, a laser-coupled fiber tip was once processed to contain a certain amount of Ti with a depth of 100 µm from the tip surface so that the laser energy could be efficiently absorbed to be transferred to thermal energy. With consecutive laser pulse irradiation, the tip processed fiber (TP fiber) served as a reproducible fine heat source whose temperature was measured to be in excess 3100 K based on two-color thermometry. Processing of ceramic and niobium plate, which are hardly ablated with direct low power (6 W) irradiation, was successfully demonstrated by contacting the TP fiber excited with the same power.

  10. A high-energy, high-flux source of gamma-rays from all-optical non-linear Thomson scattering

    NASA Astrophysics Data System (ADS)

    Corvan, D. J.; Zepf, M.; Sarri, G.

    2016-09-01

    γ-Ray sources are among the most fundamental experimental tools currently available to modern physics. As well as the obvious benefits to fundamental research, an ultra-bright source of γ-rays could form the foundation of scanning of shipping containers for special nuclear materials and provide the bases for new types of cancer therapy. However, for these applications to prove viable, γ-ray sources must become compact and relatively cheap to manufacture. In recent years, advances in laser technology have formed the cornerstone of optical sources of high energy electrons which already have been used to generate synchrotron radiation on a compact scale. Exploiting the scattering induced by a second laser, one can further enhance the energy and number of photons produced provided the problems of synchronisation and compact γ-ray detection are solved. Here, we report on the work that has been done in developing an all-optical and hence, compact non-linear Thomson scattering source, including the new methods of synchronisation and compact γ-ray detection. We present evidence of the generation of multi-MeV (maximum 16-18 MeV) and ultra-high brilliance (exceeding 1020 photons s-1mm-2mrad-2 0.1% BW at 15 MeV) γ-ray beams. These characteristics are appealing for the paramount practical applications mentioned above.

  11. Vacuum insulation of the high energy negative ion source for fusion application.

    PubMed

    Kojima, A; Hanada, M; Hilmi, A; Inoue, T; Watanabe, K; Taniguchi, M; Kashiwagi, M; Umeda, N; Tobari, H; Kobayashi, S; Yamano, Y; Grisham, L R

    2012-02-01

    Vacuum insulation on a large size negative ion accelerator with multiple extraction apertures and acceleration grids for fusion application was experimentally examined and designed. In the experiment, vacuum insulation characteristics were investigated in the JT-60 negative ion source with >1000 apertures on the grid with the surface area of ∼2 m(2). The sustainable voltages varied with a square root of the gap lengths between the grids, and decreased with number of the apertures and with the surface area of the grids. Based on the obtained results, the JT-60SA (super advanced) negative ion source is designed to produce 22 A, 500 keV D(-) ion beams for 100 s. PMID:22380274

  12. Vacuum insulation of the high energy negative ion source for fusion application

    SciTech Connect

    Kojima, A.; Hanada, M.; Inoue, T.; Watanabe, K.; Taniguchi, M.; Kashiwagi, M.; Umeda, N.; Tobari, H.; Hilmi, A.; Kobayashi, S.; Yamano, Y.; Grisham, L. R.

    2012-02-15

    Vacuum insulation on a large size negative ion accelerator with multiple extraction apertures and acceleration grids for fusion application was experimentally examined and designed. In the experiment, vacuum insulation characteristics were investigated in the JT-60 negative ion source with >1000 apertures on the grid with the surface area of {approx}2 m{sup 2}. The sustainable voltages varied with a square root of the gap lengths between the grids, and decreased with number of the apertures and with the surface area of the grids. Based on the obtained results, the JT-60SA (super advanced) negative ion source is designed to produce 22 A, 500 keV D{sup -} ion beams for 100 s.

  13. A New Paradigm for Identification of Classes of High Energy Gamma-Ray Sources

    SciTech Connect

    Torres, D F; Reimer, O

    2005-04-08

    A large fraction of the expected number of source detections of the forthcoming observatory Gamma-ray Large Area Space Telescope (GLAST) will be initially unidentified. We argue that traditional methodological approaches to identify individual detections and/or populations of gamma-ray sources present procedural limitations. These limitations will hamper our ability to classify the populations lying in the anticipated dataset with the required degree of confidence, in particular for those for which no member has yet been detected convincingly with the predecessor experiment EGRET. Here we suggest a new paradigm for achieving the classification of gamma-ray source populations that is based on implementing an a priori protocol to search for theoretically-motivated candidates. It is essential that such paradigm will be defined before the data is unblinded, in order to protect the discovery potential of the sample. Key to the new procedure is a quantitative assessment of the confidence level by which new populations can be claimed to have been discovered. When needed, small number statistics is applied for population studies in gamma-ray astronomy. Although we refer here explicitly only to the case of GLAST, the scheme we present can certainly be adapted to other experiments confronted with a similar combination of problems.

  14. A new array for the study of ultra high energy gamma-ray sources

    NASA Technical Reports Server (NTRS)

    Brooke, G.; Lambert, A.; Ogden, P. A.; Reid, R. J. O.; Patel, M.; Ferrett, J. C.; Watson, A. A.; West, A. A.

    1985-01-01

    The design and operation of a 32 x 1 10 to the 15th power sq m array of scintillation detectors for the detection of 10 to the 15th power eV cosmic rays is described with an expected angular resolution of 1 deg, thus improving the present signal/background ratio for gamma ray sources. Data are recorded on a hybrid CAMAC, an in-house system which uses a laser and Pockel-Cell arrangement to routinely calibrate the timing stability of the detectors.

  15. Broadband High-Energy Observations of the Superluminal Jet Source GRO J1655-40 During an Outburst

    NASA Technical Reports Server (NTRS)

    Zhang, S. N.; Ebisawa, K.; Sunyaev, R.; Ueda, Y.; Harmon, B. A.; Sazonov, S.; Fishman, G. J.; Inoue, H.; Paciesas, W. S.; Takahash, T.

    1997-01-01

    The X-ray/radio transient superluminal jet source GRO J1655-40 was recently suggested to contain a black hole from optical observations. Because it is a relatively close-by system (d approximately 3.2 kpc), it can likely provide us with rich information about the physics operating in both Galactic and extragalactic jet sources. We present the first simultaneous broadband high-energy observations of GRO J1655-40 during the 1995 July-August outburst by three instruments: ASCA, WATCH/Granat, and BATSE/CGRO, in the energy band from 1 keV to 2 MeV. Our observations strengthen the interpretation that GRO J1655-40 contains a black hole. We detected a two-component energy spectrum, commonly seen from other Galactic black hole binaries, but never detected from a neutron star system. Combining our results with the mass limits derived from optical radial velocity and orbital period measurements, we further constrain the mass of the central object to be between 3.3 and 5.8 solar mass, above the well-established mass upper limit of 3.2 solar mass for a neutron star (the optical mass function for GRO J1655-40 is 3.16 + 0.2 solar mass). This system is therefore the first Galactic superluminal jet source for which there is strong evidence that the system contains a stellar mass black hole. The inclination angle of the binary system is constrained to be between 76 deg and 87 deg, consistent with estimates obtained from optical light curves and radio jet kinematics.

  16. Optimizing the Operation of a Vertical Johann Spectrometer Using a High Energy Fluorescer X-ray Source

    SciTech Connect

    Haugh, Michael; Stewart, Richard

    2010-10-01

    This paper describes the operation and testing for a Vertical Johann Spectrometer (VJS) operating in the 13 keV range. The spectrometer is designed to use thin curved mica crystals or thick germanium crystals. The VJS must have a resolution E/ΔE=3000 or better to measure Doppler broadening of highly ionized krypton and operate at a small X-ray angle in order to be used as a diagnostic in a laser plasma target chamber. The VJS was aligned, tested, and optimized using a fluorescer type high energy X-ray (HEX) source located at National Security Technologies, LLC (NSTec), in Livermore, California. The HEX uses a 160 kV X-ray tube to excite fluorescence from various targets. Both rubidium and bismuth fluorescers were used for this effort. This presentation describes the NSTec HEX system and the methods used to optimize and characterize the VJS performance.

  17. Detection of spatially extended sources in high energy astrophysics with special application to lunar occultation

    NASA Astrophysics Data System (ADS)

    Jenke, Peter Alexander

    2009-01-01

    Occultation is a technique that enables image reconstruction and source identification with a non-imaging detector. Such an approach is well suited for a future survey mission in nuclear astrophysics. In particular, the Lunar Occultation Technique (LOT) utilizes the Moon as an occulting object and is the basis of a new gamma-ray survey mission concept, the Lunar OCcultation Observer (LOCO). Techniques utilizing the LOT to detect spatially extended emission, from the Galactic plane or Galactic Center region, have been developed. Given knowledge of detector position in lunar orbit, combined with lunar ephemeris and relevant coordinate transformations, occultation time series can be used to reconstruct skymaps of these extended Galactic emitters. Monte-Carlo Markov Chains (MCMC), incorporating the Metropolis-Hastings algorithm for parametric model testing, form the basis of the technique. Performance of the imaging methodology, and its application to nuclear astrophysics will be presented.

  18. Development of a Position Sensitive Neutron Detector with High Efficiency and Energy Resolution for Use at High-Flux Beam Sources

    PubMed Central

    Markoff, Diane M.; Cianciolo, Vince; Britton, Chuck L.; Cooper, Ronald G.; Greene, Geoff L.

    2005-01-01

    We are developing a high-efficiency neutron detector with 1 cm position resolution and coarse energy resolution for use at high-flux neutron source facilities currently proposed or under construction. The detector concept integrates a segmented 3He ionization chamber with the position sensitive, charged particle collection methods of a MicroMegas detector. Neutron absorption on the helium produces protons and tritons that ionize the fill gas. The charge is amplified in the field region around a wire mesh and subsequently detected in current mode by wire strips mounted on a substrate. One module consisting of a high-voltage plate, a field-shaping high-voltage plate, a grid and wire strips defines a detection region. For 100 % efficiency, detector modules are consecutively placed along the beam axis. Analysis over several regions with alternating wire strip orientation provides a two-dimensional beam profile. By using 3He, a 1/v absorption gas, each axial region captures neutrons of a different energy range, providing an energy-sensitive detection scheme especially useful at continuous beam sources. PMID:27308166

  19. Development of a Position Sensitive Neutron Detector with High Efficiency and Energy Resolution for Use at High-Flux Beam Sources.

    PubMed

    Markoff, Diane M; Cianciolo, Vince; Britton, Chuck L; Cooper, Ronald G; Greene, Geoff L

    2005-01-01

    We are developing a high-efficiency neutron detector with 1 cm position resolution and coarse energy resolution for use at high-flux neutron source facilities currently proposed or under construction. The detector concept integrates a segmented (3)He ionization chamber with the position sensitive, charged particle collection methods of a MicroMegas detector. Neutron absorption on the helium produces protons and tritons that ionize the fill gas. The charge is amplified in the field region around a wire mesh and subsequently detected in current mode by wire strips mounted on a substrate. One module consisting of a high-voltage plate, a field-shaping high-voltage plate, a grid and wire strips defines a detection region. For 100 % efficiency, detector modules are consecutively placed along the beam axis. Analysis over several regions with alternating wire strip orientation provides a two-dimensional beam profile. By using (3)He, a 1/v absorption gas, each axial region captures neutrons of a different energy range, providing an energy-sensitive detection scheme especially useful at continuous beam sources. PMID:27308166

  20. Suzaku Observation of the Unidentified Very High Energy Gamma-Ray Source HESS J1702-420

    NASA Astrophysics Data System (ADS)

    Fujinaga, Takahisa; Bamba, Aya; Dotani, Tadayasu; Ozaki, Masanobu; Pü:Hlhofer, Gerd; Wagner, Stefan; Reimer, Olaf; Funk, Stefan; Hinton, Jim

    2011-11-01

    A deep X-ray observation of the unidentified very high energy (VHE) gamma-ray source HESS J1702-420, for the first time, was carried out by Suzaku. No bright sources were detected in the XIS field of view (FOV), except for two faint point-like sources. The two sources, however, are considered not to be related to HESS J1702-420, because their fluxes in the 2-10 keV band (˜10-14 erg s-1 cm-2) are ˜3 orders of magnitude smaller than the VHE gamma-ray flux in the 1-10 TeV band (FTeV = 3.1 × 10-11 erg s-1 cm-2). We compared the energy spectrum of diffuse emission, extracted from the entire XIS FOV with those from nearby observations. If we consider the systematic error of background subtraction, no significant diffuse emission was detected with an upper limit of FX < 2.7 × 10-12 erg s-1 cm-2 in the 2-10 keV band for an assumed power-law spectrum of Γ = 2.1 and a source size same as that in the VHE band. The upper limit of the X-ray flux is twelve-times as small as the VHE gamma-ray flux. The large flux ratio (FTeV/FX) indicates that HESS J1702-420 is another example of a ``dark'' particle accelerator. If we use a simple one-zone leptonic model, in which VHE gamma-rays are produced through inverse Compton scattering of the cosmic microwave background and interstellar far-infrared emission, and the X-rays via the synchrotron mechanism, an upper limit of the magnetic field (1.7μG), is obtained from the flux ratio. Because the magnetic field is weaker than the typical value in the galactic plane (3-10 νG), the simple one-zone model may not work for HESS J1702-420 and a significant fraction of the VHE gamma-rays may originate from protons.

  1. Axion-like particle effects on the polarization of cosmic high-energy gamma sources

    SciTech Connect

    Bassan, Nicola; Mirizzi, Alessandro; Roncadelli, Marco E-mail: alessandro.mirizzi@desy.de

    2010-05-01

    Various satellite-borne missions are being planned to measure the polarization of a large number of gamma-ray bursts (GRBs). We show that the polarization pattern resulting from the current models of GRB emission can be drastically modified by the existence of very light axion-like particles (ALPs), which are predicted by many extensions of the Standard Model of particle physics. Basically, the propagation of photons emitted by a GRB through cosmic magnetic fields with a domain-like structure induces photon-ALP mixing, which is expected to produce a strong modification of the initial photon polarization. Because of the random orientation of the magnetic field in each domain, this effect strongly depends on the orientation of the line of sight. As a consequence, photon-ALP conversion considerably broadens the initial polarization distribution. Searching for such a peculiar feature through future high-statistics polarimetric measurements therefore offers a new opportunity to discover very light ALPs.

  2. Fission Energy and Other Sources of Energy

    ERIC Educational Resources Information Center

    Alfven, Hannes

    1974-01-01

    Discusses different forms of energy sources and basic reasons for the opposition to the use of atomic energy. Suggests that research efforts should also be aimed toward the fission technology to make it acceptable besides major research studies conducted in the development of alternative energy sources. (CC)

  3. Blazars as Ultra-high-energy Cosmic-ray Sources: Implications for TeV Gamma-Ray Observations

    NASA Astrophysics Data System (ADS)

    Murase, Kohta; Dermer, Charles D.; Takami, Hajime; Migliori, Giulia

    2012-04-01

    The spectra of BL Lac objects and Fanaroff-Riley I radio galaxies are commonly explained by the one-zone leptonic synchrotron self-Compton (SSC) model. Spectral modeling of correlated multiwavelength data gives the comoving magnetic field strength, the bulk outflow Lorentz factor, and the emission region size. Assuming the validity of the SSC model, the Hillas condition shows that only in rare cases such sources accelerate protons to much above 1019 eV, so >~ 1020 eV ultra-high-energy cosmic rays (UHECRs) are likely to be heavy ions if powered by this type of radio-loud active galactic nuclei (AGNs). Survival of nuclei is shown to be possible in TeV BL Lacs and misaligned counterparts with weak photohadronic emissions. Another signature of hadronic production is intergalactic UHECR-induced cascade emission, which is an alternative explanation of the TeV spectra of some extreme non-variable blazars such as 1ES 0229+200 or 1ES 1101-232. We study this kind of cascade signal, taking into account effects of the structured extragalactic magnetic fields in which the sources should be embedded. We demonstrate the importance of cosmic-ray deflections on the γ-ray flux, and show that required absolute cosmic-ray luminosities are larger than the average UHECR luminosity inferred from UHECR observations and can even be comparable to the Eddington luminosity of supermassive black holes. Future TeV γ-ray observations using the Cerenkov Telescope Array and the High Altitude Water Cerenkov detector array can test for UHECR acceleration by observing >25 TeV photons from relatively low redshift sources such as 1ES 0229+200, and gsimTeV photons from more distant radio-loud AGNs.

  4. BLAZARS AS ULTRA-HIGH-ENERGY COSMIC-RAY SOURCES: IMPLICATIONS FOR TeV GAMMA-RAY OBSERVATIONS

    SciTech Connect

    Murase, Kohta; Dermer, Charles D.; Takami, Hajime; Migliori, Giulia

    2012-04-10

    The spectra of BL Lac objects and Fanaroff-Riley I radio galaxies are commonly explained by the one-zone leptonic synchrotron self-Compton (SSC) model. Spectral modeling of correlated multiwavelength data gives the comoving magnetic field strength, the bulk outflow Lorentz factor, and the emission region size. Assuming the validity of the SSC model, the Hillas condition shows that only in rare cases such sources accelerate protons to much above 10{sup 19} eV, so {approx}> 10{sup 20} eV ultra-high-energy cosmic rays (UHECRs) are likely to be heavy ions if powered by this type of radio-loud active galactic nuclei (AGNs). Survival of nuclei is shown to be possible in TeV BL Lacs and misaligned counterparts with weak photohadronic emissions. Another signature of hadronic production is intergalactic UHECR-induced cascade emission, which is an alternative explanation of the TeV spectra of some extreme non-variable blazars such as 1ES 0229+200 or 1ES 1101-232. We study this kind of cascade signal, taking into account effects of the structured extragalactic magnetic fields in which the sources should be embedded. We demonstrate the importance of cosmic-ray deflections on the {gamma}-ray flux, and show that required absolute cosmic-ray luminosities are larger than the average UHECR luminosity inferred from UHECR observations and can even be comparable to the Eddington luminosity of supermassive black holes. Future TeV {gamma}-ray observations using the Cerenkov Telescope Array and the High Altitude Water Cerenkov detector array can test for UHECR acceleration by observing >25 TeV photons from relatively low redshift sources such as 1ES 0229+200, and {approx}>TeV photons from more distant radio-loud AGNs.

  5. The high energy spherical grating monochromator minus A new source of soft x rays at Daresbury (abstract)

    SciTech Connect

    Surman, M.; Cragg-Hine, I.; Singh, J.; Bowler, B.; Padmore, H.A.; Norman, D. ); Johnson, A.L.; Atrei, A.; Walter, W.K.; King, D.A. ); Davis, R.; Purcell, K.G.; Thornton, G. )

    1992-01-01

    In this article we report the characteristics of the new High Energy Spherical Grating Monochromator beam line on the SRS. The instrument, which has no entrance slit, was designed to provide high photon flux with small spot size, in the energy range covering the 1s binding energies of carbon, nitrogen, oxygen, and fluorine. Radiation from a bending magnet is horizontally focused onto the exit slit by a long, Pt-coated meridian cylinder ({ital R}=299 m, 2 mrad horiz. aperture, 2{degree} glancing angle). The light is vertically diffracted and focused by one of three interchangeable spherical gratings (1050, 1500, and 1800 lines mm{sup {minus}1}) operating in negative order. Finally, the light is refocused by an ellipsoidal mirror. The photon flux, determined with copper and carbon photocathodes, is presented for the three gratings. Useful flux is obtained in the range 250--1200 eV, with intensity maxima for each grating at 600, 700, and 800 eV of 11, 9, and 5{times}10{sup 10} photons s{sup {minus}1} per 100-mA stored beam into a band pass of 0.05%. The influence of contaminants which are present on the optical elements is discussed, together with details of beam line operating conditions which minimize the build up of such contaminants. Photoabsorption and photoemission measurements indicate a high (up to 30%) second order and some third order light content. Resolution determinations obtained from photoabsorption measurements are presented. Although features as narrow as 250 meV have been resolved, the resolving power of the instrument is found to depend strongly on stored beam current. We suggest this may be due to electron beam (i.e., source) blow-up. We critically discuss the suitability of the new facility for surface EXAFS of low {ital Z} adsorbates, in particular above the carbon, nitrogen, and oxygen 1s edges, using examples from recent studies which have been undertaken on the beamline.

  6. Advances in the Two Source Energy Balance (TSEB) model using very high resolution remote sensing data in vineyards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The thermal-based Two Source Energy Balance (TSEB) model partitions the water and energy fluxes from vegetation and soil components providing thus the ability for estimating soil evaporation (E) and canopy transpiration (T) separately. However, it is crucial for ET partitioning to retrieve reliable ...

  7. Developing a bright 17 keV x-ray source for probing high-energy-density states of matter at high spatial resolution

    SciTech Connect

    Huntington, C. M.; Park, H.-S.; Maddox, B. R.; Barrios, M. A.; Benedetti, R.; Braun, D. G.; Landen, O. L.; Wehrenberg, C. E.; Remington, B. A.; Hohenberger, M.; Regan, S. P.

    2015-04-15

    A set of experiments were performed on the National Ignition Facility (NIF) to develop and optimize a bright, 17 keV x-ray backlighter probe using laser-irradiated Nb foils. High-resolution one-dimensional imaging was achieved using a 15 μm wide slit in a Ta substrate to aperture the Nb He{sub α} x-rays onto an open-aperture, time integrated camera. To optimize the x-ray source for imaging applications, the effect of laser pulse shape and spatial profile on the target was investigated. Two laser pulse shapes were used—a “prepulse” shape that included a 3 ns, low-intensity laser foot preceding the high-energy 2 ns square main laser drive, and a pulse without the laser foot. The laser spatial profile was varied by the use of continuous phase plates (CPPs) on a pair of shots compared to beams at best focus, without CPPs. A comprehensive set of common diagnostics allowed for a direct comparison of imaging resolution, total x-ray conversion efficiency, and x-ray spectrum between shots. The use of CPPs was seen to reduce the high-energy tail of the x-ray spectrum, whereas the laser pulse shape had little effect on the high-energy tail. The measured imaging resolution was comparably high for all combinations of laser parameters, but a higher x-ray flux was achieved without phase plates. This increased flux was the result of smaller laser spot sizes, which allowed us to arrange the laser focal spots from multiple beams and produce an x-ray source which was more localized behind the slit aperture. Our experiments are a first demonstration of point-projection geometry imaging at NIF at the energies (>10 keV) necessary for imaging denser, higher-Z targets than have previously been investigated.

  8. High-energy in-beam neutron measurements of metal-based shielding for accelerator-driven spallation neutron sources

    NASA Astrophysics Data System (ADS)

    DiJulio, D. D.; Cooper-Jensen, C. P.; Björgvinsdóttir, H.; Kokai, Z.; Bentley, P. M.

    2016-05-01

    Metal-based shielding plays an important role in the attenuation of harmful and unwanted radiation at an accelerator-driven spallation neutron source. At the European Spallation Source, currently under construction in Lund, Sweden, metal-based materials are planned to be used extensively as neutron guide substrates in addition to other shielding structures around neutron guides. The usage of metal-based materials in the vicinity of neutron guides however requires careful consideration in order to minimize potential background effects in a neutron instrument at the facility. Therefore, we have carried out a combined study involving high-energy neutron measurements and Monte Carlo simulations of metal-based shielding, both to validate the simulation methodology and also to investigate the benefits and drawbacks of different metal-based solutions. The measurements were carried out at The Svedberg Laboratory in Uppsala, Sweden, using a 174.1 MeV neutron beam and various thicknesses of aluminum-, iron-, and copper-based shielding blocks. The results were compared to geant4 simulations and revealed excellent agreement. Our combined study highlights the particular situations where one type of metal-based solution may be preferred over another.

  9. Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source

    SciTech Connect

    Barkusky, Frank; Bayer, Armin; Peth, Christian; Mann, Klaus

    2009-01-01

    In order to perform material interaction studies with intense extreme ultraviolet (EUV) radiation, a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10x demagnified imaging of the plasma a maximum pulse energy density of {approx}0.73 J/cm{sup 2} at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate, polycarbonate, and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data, etch rates were determined, revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore, the surface roughness of the structured polymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface, indicating a rather smooth etch process (roughness increase of 20%-30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates, having consequences for the proper use of polymer ablation for beam profiling of focused EUV radiation.

  10. Feasibility of producing a short, high energy s-band linear accelerator using a klystron power source

    SciTech Connect

    Baillie, Devin; Aubin, J. St.; Fallone, B. G.; Steciw, S.

    2013-04-15

    Purpose: To use a finite-element method (FEM) model to study the feasibility of producing a short s-band (2.9985 GHz) waveguide capable of producing x-rays energies up to 10 MV, for applications in a linac-MR, as well as conventional radiotherapy. Methods: An existing waveguide FEM model developed by the authors' group is used to simulate replacing the magnetron power source with a klystron. Peak fields within the waveguide are compared with a published experimental threshold for electric breakdown. The RF fields in the first accelerating cavity are scaled, approximating the effect of modifications to the first coupling cavity. Electron trajectories are calculated within the RF fields, and the energy spectrum, beam current, and focal spot of the electron beam are analyzed. One electron spectrum is selected for Monte Carlo simulations and the resulting PDD compared to measurement. Results: When the first cavity fields are scaled by a factor of 0.475, the peak magnitude of the electric fields within the waveguide are calculated to be 223.1 MV/m, 29% lower than the published threshold for breakdown at this operating frequency. Maximum electron energy increased from 6.2 to 10.4 MeV, and beam current increased from 134 to 170 mA. The focal spot FWHM is decreased slightly from 0.07 to 0.05 mm, and the width of the energy spectrum increased slightly from 0.44 to 0.70 MeV. Monte Carlo results show d{sub max} is at 2.15 cm for a 10 Multiplication-Sign 10 cm{sup 2} field, compared with 2.3 cm for a Varian 10 MV linac, while the penumbral widths are 4.8 and 5.6 mm, respectively. Conclusions: The authors' simulation results show that a short, high-energy, s-band accelerator is feasible and electric breakdown is not expected to interfere with operation at these field strengths. With minor modifications to the first coupling cavity, all electron beam parameters are improved.

  11. High resolution monochromator for inelastic scattering studies of high energy phonons using undulator radiation at the advanced photon source

    SciTech Connect

    Macrander, A.T.; Schwoerer-Boehning, M.; Abbamonte, P.M.; Hu, M.

    1997-08-01

    A monochromator for use at 13.84 keV with a calculated bandpass of 5.2 meV was designed built, and tested. Tuning was performed by rotating the inner crystal of a pair of nested silicon channel-cut crystals. The inner crystal employs the (884) reflection, and the outer crystal employs a collimating asymmetric (422) reflection (dynamical asymmetry factor, b, equal to {minus}17.5). Tests were done with a double-crystal Si(111) pre-monochromator situated upstream of the high resolution monochromator and a Si(777) backscattering crystal situated downstream. For this optical arrangement an ideal value of 6.3 meV as calculated by x-ray dynamical diffraction theory applies for the FWHM of the convolution of the net monochromator reflectivity function with that of the Si(777) reflection. This calculated value is to be compared to the value of 7.1 meV measured by tuning the high resolution monochromator. Measured efficiencies were less than ideal by a factor of 3.2 to 4.9, where the larger flux reduction factors were found with higher positron storage ring currents.

  12. Two-source energy balance model evaluation for mapping evapotranspiration on the semi-arid Southern High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evapotranspiration (ET) is an essential component of the water balance and a major consumptive use of irrigation water and precipitation on cropland. In this study, we applied the Two-Source Energy Balance (T-SEB) model to estimate hourly ET from the Landsat Thematic Mapper (TM) data for the semi-ar...

  13. High Intensity Polarized Electron Sources

    NASA Astrophysics Data System (ADS)

    Poelker, M.; Adderley, P.; Brittian, J.; Clark, J.; Grames, J.; Hansknecht, J.; McCarter, J.; Stutzman, M. L.; Suleiman, R.; Surles-Law, K.

    2008-02-01

    During the 1990s, at numerous facilities world wide, extensive R&D devoted to constructing reliable GaAs photoguns helped ensure successful accelerator-based nuclear and high-energy physics programs using spin polarized electron beams. Today, polarized electron source technology is considered mature, with most GaAs photoguns meeting accelerator and experiment beam specifications in a relatively trouble-free manner. Proposals for new collider facilities however, require electron beams with parameters beyond today's state-of-the-art and serve to renew interest in conducting polarized electron source R&D. And at CEBAF/Jefferson Lab, there is an immediate pressing need to prepare for new experiments that require considerably more beam current than before. One experiment in particular—Q-weak, a parity violation experiment that will look for physics beyond the Standard Model—requires 180 uA average current at polarization >80% for a duration of one year, with run-averaged helicity correlated current asymmetry less than 0.1 ppm. Neighboring halls will continue taking beam during Q-weak, pushing the total average beam current from the gun beyond 300 uA. This workshop contribution describes R&D at Jefferson Lab, dedicated toward extending the operating current of polarized electron sources to meet the requirements of high current experiments at CEBAF and to better appreciate the technological challenges of new accelerators, particularly high average current machines like eRHIC that require at least 25 mA at high polarization.

  14. Two-Source Energy Balance Model Evaluation for Mapping Evapotranspiration on the Semi- arid Southern High Plains

    NASA Astrophysics Data System (ADS)

    Gowda, P. H.; Chavez, J. L.; Colaizzi, P. D.; Evett, S. R.; Howell, T. A.; Copeland, K.

    2007-05-01

    Evapotranspiration (ET) is an essential component of the water balance and a major consumptive use of irrigation water and precipitation on cropland. In this study, we applied the Two-Source Energy Balance (T-SEB) model to estimate hourly ET from Landsat Thematic Mapper (TM) data for the semi-arid Southern High Plains of the United States where more than 90 percent of the groundwater withdrawals are used for irrigation. For this purpose, a Landsat TM image covering a major portion of the Southern High Plains (parts of Texas Panhandle and northeastern New Mexico) was acquired for 23 July 2006 for the overpass at 11:26 AM CST. Atmospheric correction on the TM imagery was done using MODTRAN, an atmospheric radiative transfer model. Comprehensive ground-truth data were collected to develop a detailed land use map showing major crops grown in the region. Performance of the T SEB model was evaluated by comparing mapped ET data with measured hourly ET data on five weighing lysimeters at Bushland, TX [35 Deg. 11' N, 102 Deg. 06' W; 1,170 m elevation MSL] managed by the Conservation and Production Research Laboratory, USDA-ARS. Lysimeter-measured ET rates varied from 0.24 to 0.71 mm/h. Comparison of estimated hourly mapped ET values with lysimetric measurements had an accuracy within 6% of the measured ET (r2=0.99), with a root mean squared error of 0.03 mm/h. These results support the use of the T-SEB model for the semi-arid Southern High Plains; however, more evaluation is needed for different agroclimatological conditions in the region.

  15. Economics and energy sources.

    PubMed

    Munro, Malcolm G

    2013-01-01

    Energy-based instrumentation has not only facilitated the rapid adoption of laparoscopic surgery, but could be considered essential for the completion of abdominal and pelvic procedures under endoscopic guidance. For decades, relatively simple and generic reusable monopolar and bipolar systems were the only options available. More recently, the available options for energy-based surgical instrumentation have become more crowded with the introduction of ultrasound-based cutting and sealing instruments and proprietary, impedance monitoring radiofrequency coagulation devices. Such instrumentation is presented as being easier to use as well as providing greater safety and efficacy. However, these new instruments typically require the expenditure of capital for proprietary energy generators and are usually designed to be for single use, a circumstance that increases per case costs, a circumstance that begs the question of value. Do the additional costs expended for the more expensive devices translate into reduced complications, faster operating time, or even wider access to minimally invasive procedures because they enable more surgeons to offer the service? Herein is explored the complex economic issues associated with the use of energy-based surgical devices as they apply to minimal access surgery in general and to laparoscopic procedures specifically. PMID:23659752

  16. Energy Sources, Teacher's Guide.

    ERIC Educational Resources Information Center

    Karplus, Robert

    The unit presented in this teacher's guide is the first of two developed for the fifth year in the Science Curriculum Improvement Study (SCIS) curriculum. Attention is focused on energy transfers involved in the interaction of matter in solid, liquid, and gaseous forms. The chapters are presented in six parts which include activities for reviewing…

  17. [Pollution and alternative energy sources].

    PubMed

    Melino, C

    1989-01-01

    In order to reach higher standards of living, man has always been interested in searching new energy sources. Natural energy from sun, wind and water has been overcame by more sophisticated resources such as coal, vapour, hydroelectricity, natural gas, petroleum, and, at least, nuclear energy. However all these resources present unwanted effects, namely various hazards to man and environment. On this matter society is quering the risk-benefit balance of some energy choices and optimum performance with new safety means to limit dangerousness are being pursued and developed. It is necessary to evaluate carefully every aspect of safety without under-estimating or over-evaluating problems. For each energy source a "real price" has to be paired, even more in the future, since more energy will be required to guarantee the necessary technological progress linked to a better quality of life. In the present review all risks related to different energy sources are described and discussed aiming at defining: 1) specific risks for different sources 2) benefit from their utilization 3) means of defence guaranteeing security for man and environment. Italy is strictly dependent for energy production, which comes for 80% from abroad. An appropriate balance is required considering economical and social factors and real availability of energy. This balance needs therefore to be clearly evaluated hoping in a better future for an alternative energy, less dangerous and more clear, such as that from nuclear fusion. PMID:2483087

  18. VEDCO energy installations sources

    SciTech Connect

    McDonald, A.

    1996-12-31

    A process for solid waste management is described. The approach combines materials recovery, recycling, and using refuse-derived fuel for cogeneration. A fluidized bed system is used for combustion. An example of the use of this system is briefly cited; it has extended landfill life up to 100 years for one county and allowed three counties to close municipal landfills. Over 50,000 tons of material are recycled each year, saving more than $100 million on waste disposal. Energy generation saves a chemical company over 3 million gallons of oil annually and allows the local utility company to save 75,000 tons of coal. Air emissions at the chemical company will also be reduced by over 50%.

  19. Alternative energy sources for agriculture

    SciTech Connect

    Baird, D.

    1981-05-01

    The following energy systems are discussed as alternative sources of energy for agriculture and potential demonstration projects in vocational agriculture programs: solar water heating, solar greenhouse heating, solar crop drying, gasification of wood or crop residues, and methane generation from livestock wastes. 13 references.

  20. What Did We Learn From Chandra, Xmm-Newton And Fermi-Lat About The High Energy Emission In Young Radio Sources?

    NASA Astrophysics Data System (ADS)

    Siemiginowska, Aneta; Guainazzi, M.; Hardcastle, M.; Kelly, B. C.; Kunert-Bajraszewska, M.; Migliori, G.; Sobolewska, M.; Stawarz, L.

    2013-04-01

    Giga-Hertz Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) radio sources comprise a large population of compact objects with radio emission fully contained within the innermost regions of the host galaxy (< a few kpc). Spectral and kinematic age measurements indicate their young age (typically < thousands years and in some cases less a few hundred years). These sources provide the important insights to the initial phase of the jet formation, radio source growth, source evolution and the jet impact on the ISM in the very central regions of the host galaxy. We have obtained Chandra and XMM-Newton observations for a large sample of these sources over several observing cycles. Our most recent Chandra observations targeted Compact Symmetric Objects (CSO) associated with the nuclear regions of nearby galaxies. All these CSO have measured kinematic ages within 100-3000 year old. I will present the results of our ongoing observing program focusing on the high energy properties of these young sources.

  1. High-charge-state ion sources

    SciTech Connect

    Clark, D.J.

    1983-06-01

    Sources of high charge state positive ions have uses in a variety of research fields. For heavy ion particle accelerators higher charge state particles give greater acceleration per gap and greater bending strength in a magnet. Thus higher energies can be obtained from circular accelerators of a given size, and linear accelerators can be designed with higher energy gain per length using higher charge state ions. In atomic physics the many atomic transitions in highly charged ions supplies a wealth of spectroscopy data. High charge state ion beams are also used for charge exchange and crossed beam experiments. High charge state ion sources are reviewed. (WHK)

  2. Energy sources for intravenous nutrition

    PubMed Central

    Rowlands, B J

    1987-01-01

    Controversy exists concerning the appropriate use of carbohydrate solutions and fat emulsions as energy sources in intravenous nutritional regimens. Current evidence suggests that glucose is the carbohydrate energy source of choice and that when infused with appropriate quantities of protein it provides cheap and effective nutritional support in the majority of patients and clinical circumstances. During glucose infusion, blood glucose and acid-base balance should be closely monitored and, when indicated, exogenous insulin should be added to the regimen to combat hyperglycaemia and improve protein anabolism. Fat emulsions, although expensive, may justifiably be used in patients with moderate or severe stress to provide up to 50% of non-protein energy, especially in circumstances where attempts to satisfy energy requirements exclusively with glucose would impose an additional metabolic stress. PMID:3109093

  3. High intensity, pulsed thermal neutron source

    DOEpatents

    Carpenter, J.M.

    1973-12-11

    This invention relates to a high intensity, pulsed thermal neutron source comprising a neutron-producing source which emits pulses of fast neutrons, a moderator block adjacent to the last neutron source, a reflector block which encases the fast neutron source and the moderator block and has a thermal neutron exit port extending therethrough from the moderator block, and a neutron energy- dependent decoupling reflector liner covering the interior surfaces of the thermal neutron exit port and surrounding all surfaces of the moderator block except the surface viewed by the thermal neutron exit port. (Official Gazette)

  4. Radiation sources with planar wire arrays and planar foils for inertial confinement fusion and high energy density physics research

    SciTech Connect

    Kantsyrev, V. L.; Safronova, A. S.; Esaulov, A. A.; Shrestha, I.; Astanovitsky, A.; Osborne, G. C.; Shlyaptseva, V. V.; Weller, M. E.; Keim, S.; Stafford, A.; Cooper, M.; Chuvatin, A. S.; Rudakov, L. I.; Velikovich, A. L.

    2014-03-15

    This article reports on the joint success of two independent lines of research, each of them being a multi-year international effort. One of these is the development of innovative sources, such as planar wire arrays (PWAs). PWAs turned out to be a prolific radiator, which act mainly as a resistor, even though the physical mechanism of efficient magnetic energy conversion into radiation still remains unclear. We review the results of our extensive studies of PWAs. We also report the new results of the experimental comparison PWAs with planar foil liners (another promising alternative to wire array loads at multi-mega-ampere generators). Pioneered at UNR, the PWA Z-pinch loads have later been tested at the Sandia National Laboratories (SNL) on the Saturn generator, on GIT-12 machine in Russia, and on the QiangGuang-1 generator in China, always successfully. Another of these is the drastic improvement in energy efficiency of pulsed-power systems, which started in early 1980s with Zucker's experiments at Naval Research Laboratory (NRL). Successful continuation of this approach was the Load Current Multiplier (LCM) proposed by Chuvatin in collaboration with Rudakov and Weber from NRL. The 100 ns LCM was integrated into the Zebra generator, which almost doubled the plasma load current, from 0.9 to 1.7 MA. The two above-mentioned innovative approaches were used in combination to produce a new compact hohlraum radiation source for ICF, as jointly proposed by SNL and UNR [Jones et al., Phys. Rev. Lett. 104, 125001 (2010)]. The first successful proof-of-the-principle experimental implementation of new hohlraum concept at university-scale generator Zebra/LCM is demonstrated. A numerical simulation capability with VisRaD code (from PRISM Co.) established at UNR allowed for the study of hohlraum coupling physics and provides the possibility of optimization of a new hohlraum. Future studies are discussed.

  5. Radiation sources with planar wire arrays and planar foils for inertial confinement fusion and high energy density physics research

    NASA Astrophysics Data System (ADS)

    Kantsyrev, V. L.; Chuvatin, A. S.; Safronova, A. S.; Rudakov, L. I.; Esaulov, A. A.; Velikovich, A. L.; Shrestha, I.; Astanovitsky, A.; Osborne, G. C.; Shlyaptseva, V. V.; Weller, M. E.; Keim, S.; Stafford, A.; Cooper, M.

    2014-03-01

    This article reports on the joint success of two independent lines of research, each of them being a multi-year international effort. One of these is the development of innovative sources, such as planar wire arrays (PWAs). PWAs turned out to be a prolific radiator, which act mainly as a resistor, even though the physical mechanism of efficient magnetic energy conversion into radiation still remains unclear. We review the results of our extensive studies of PWAs. We also report the new results of the experimental comparison PWAs with planar foil liners (another promising alternative to wire array loads at multi-mega-ampere generators). Pioneered at UNR, the PWA Z-pinch loads have later been tested at the Sandia National Laboratories (SNL) on the Saturn generator, on GIT-12 machine in Russia, and on the QiangGuang-1 generator in China, always successfully. Another of these is the drastic improvement in energy efficiency of pulsed-power systems, which started in early 1980s with Zucker's experiments at Naval Research Laboratory (NRL). Successful continuation of this approach was the Load Current Multiplier (LCM) proposed by Chuvatin in collaboration with Rudakov and Weber from NRL. The 100 ns LCM was integrated into the Zebra generator, which almost doubled the plasma load current, from 0.9 to 1.7 MA. The two above-mentioned innovative approaches were used in combination to produce a new compact hohlraum radiation source for ICF, as jointly proposed by SNL and UNR [Jones et al., Phys. Rev. Lett. 104, 125001 (2010)]. The first successful proof-of-the-principle experimental implementation of new hohlraum concept at university-scale generator Zebra/LCM is demonstrated. A numerical simulation capability with VisRaD code (from PRISM Co.) established at UNR allowed for the study of hohlraum coupling physics and provides the possibility of optimization of a new hohlraum. Future studies are discussed.

  6. Measurement of the high energy component of the x-ray spectra in the VENUS electron cyclotron resonance ion source (abstract only)

    SciTech Connect

    Leitner, D.; Benitez, J. Y.; Lyneis, C. M.; Todd, D. S.; Ropponen, T.; Ropponen, J.; Koivisto, H.; Gammino, S.

    2008-02-15

    High performance electron cyclotron resonance (ECR) ion sources, such as VENUS (versatile ECR for nuclear science), produce large amounts of x rays. By studying their energy spectra, conclusions can be drawn about the electron heating process and the electron confinement. In addition, the bremsstrahlung from the plasma chamber is partly absorbed by the cold mass of the superconducting magnet adding an extra heat load to the cryostat. Germanium or NaI detectors are generally used for x-ray measurements. Due to the high x-ray flux from the source, the experimental setup to measure bremsstrahlung spectra from ECR ion sources is somewhat different than for the traditional nuclear physics measurements these detectors are generally used for. In particular, the collimation and background shielding can be problematic. In this paper we will discuss the experimental setup for such a measurement, the energy calibration and background reduction, the shielding of the detector, and collimation of the x-ray flux. We will present x-ray energy spectra and cryostat heating rates in dependence of various ion source parameters such as confinement fields, minimum B-field, rf power, and heating frequency.

  7. Multimessenger search for sources of gravitational waves and high-energy neutrinos: Initial results for LIGO-Virgo and IceCube

    NASA Astrophysics Data System (ADS)

    Aartsen, M. G.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Altmann, D.; Anderson, T.; Arguelles, C.; Arlen, T. C.; Auffenberg, J.; Bai, X.; Barwick, S. W.; Baum, V.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; BenZvi, S.; Berghaus, P.; Berley, D.; Bernardini, E.; Bernhard, A.; Besson, D. Z.; Binder, G.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Brayeur, L.; Bretz, H.-P.; Brown, A. M.; Casey, J.; Casier, M.; Chirkin, D.; Christov, A.; Christy, B.; Clark, K.; Classen, L.; Clevermann, F.; Coenders, S.; Cowen, D. F.; Cruz Silva, A. H.; Danninger, M.; Daughhetee, J.; Davis, J. C.; Day, M.; de André, J. P. A. M.; De Clercq, C.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; Dunkman, M.; Eagan, R.; Eberhardt, B.; Eichmann, B.; Eisch, J.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Felde, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Flis, S.; Franckowiak, A.; Frantzen, K.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gier, D.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Golup, G.; Gonzalez, J. G.; Goodman, J. A.; Góra, D.; Grandmont, D. T.; Grant, D.; Gretskov, P.; Groh, J. C.; Groß, A.; Ha, C.; Haack, C.; Haj Ismail, A.; Hallen, P.; Hallgren, A.; Halzen, F.; Hanson, K.; Hebecker, D.; Heereman, D.; Heinen, D.; Helbing, K.; Hellauer, R.; Hellwig, D.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Homeier, A.; Hoshina, K.; Huang, F.; Huelsnitz, W.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Jagielski, K.; Japaridze, G. S.; Jero, K.; Jlelati, O.; Jurkovic, M.; Kaminsky, B.; Kappes, A.; Karg, T.; Karle, A.; Kauer, M.; Kelley, J. L.; Kheirandish, A.; Kiryluk, J.; Kläs, J.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Koob, A.; Köpke, L.; Kopper, C.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Kriesten, A.; Krings, K.; Kroll, G.; Kroll, M.; Kunnen, J.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Larsen, D. T.; Larson, M. J.; Lesiak-Bzdak, M.; Leuermann, M.; Leute, J.; Lünemann, J.; Macías, O.; Madsen, J.; Maggi, G.; Maruyama, R.; Mase, K.; Matis, H. S.; McNally, F.; Meagher, K.; Medici, M.; Meli, A.; Meures, T.; Miarecki, S.; Middell, E.; Middlemas, E.; Milke, N.; Miller, J.; Mohrmann, L.; Montaruli, T.; Morse, R.; Nahnhauer, R.; Naumann, U.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke, A.; Odrowski, S.; Olivas, A.; Omairat, A.; O'Murchadha, A.; Palczewski, T.; Paul, L.; Penek, Ö.; Pepper, J. A.; Pérez de los Heros, C.; Pfendner, C.; Pieloth, D.; Pinat, E.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Pütz, J.; Quinnan, M.; Rädel, L.; Rameez, M.; Rawlins, K.; Redl, P.; Rees, I.; Reimann, R.; Resconi, E.; Rhode, W.; Richman, M.; Riedel, B.; Robertson, S.; Rodrigues, J. P.; Rongen, M.; Rott, C.; Ruhe, T.; Ruzybayev, B.; Ryckbosch, D.; Saba, S. M.; Sander, H.-G.; Sandroos, J.; Santander, M.; Sarkar, S.; Schatto, K.; Scheriau, F.; Schmidt, T.; Schmitz, M.; Schoenen, S.; Schöneberg, S.; Schönwald, A.; Schukraft, A.; Schulte, L.; Schulz, O.; Seckel, D.; Sestayo, Y.; Seunarine, S.; Shanidze, R.; Sheremata, C.; Smith, M. W. E.; Soldin, D.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stanisha, N. A.; Stasik, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strahler, E. A.; Ström, R.; Strotjohann, N. L.; Sullivan, G. W.; Taavola, H.; Taboada, I.; Tamburro, A.; Tepe, A.; Ter-Antonyan, S.; Terliuk, A.; Tešić, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Tosi, D.; Tselengidou, M.; Unger, E.; Usner, M.; Vallecorsa, S.; van Eijndhoven, N.; Vandenbroucke, J.; van Santen, J.; Vehring, M.; Voge, M.; Vraeghe, M.; Walck, C.; Wallraff, M.; Weaver, Ch.; Wellons, M.; Wendt, C.; Westerhoff, S.; Whelan, B. J.; Whitehorn, N.; Wichary, C.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Ziemann, J.; Zierke, S.; Zoll, M.; Aasi, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Affeldt, C.; Agathos, M.; Aggarwal, N.; Aguiar, O. D.; Ajith, P.; Alemic, A.; Allen, B.; Allocca, A.; Amariutei, D.; Andersen, M.; Anderson, R. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C.; Areeda, J. S.; Ast, S.; Aston, S. M.; Astone, P.; Aufmuth, P.; Augustus, H.; Aulbert, C.; Aylott, B. E.; Babak, S.; Baker, P. T.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barbet, M.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.

    2014-11-01

    We report the results of a multimessenger search for coincident signals from the LIGO and Virgo gravitational-wave observatories and the partially completed IceCube high-energy neutrino detector, including periods of joint operation between 2007-2010. These include parts of the 2005-2007 run and the 2009-2010 run for LIGO-Virgo, and IceCube's observation periods with 22, 59 and 79 strings. We find no significant coincident events, and use the search results to derive upper limits on the rate of joint sources for a range of source emission parameters. For the optimistic assumption of gravitational-wave emission energy of 10-2 M⊙c2 at ˜150 Hz with ˜60 ms duration, and high-energy neutrino emission of 1 051 erg comparable to the isotropic gamma-ray energy of gamma-ray bursts, we limit the source rate below 1.6 ×1 0-2 Mpc-3 yr-1 . We also examine how combining information from gravitational waves and neutrinos will aid discovery in the advanced gravitational-wave detector era.

  8. A K-alpha x-ray source using high energy and high repetition rate laser system for phase contrast imaging

    PubMed Central

    Fourmaux, Sylvain; Kieffer, Jean-Claude; Kincaid, Russell; Krol, Andrzej

    2009-01-01

    K-alpha x-ray sources from laser produced plasmas provide completely new possibilities for x-ray phase-contrast imaging applications. By tightly focusing intense femtosecond laser pulses onto a solid target K-alpha x-ray pulses are generated through the interaction of energetic electrons created in the plasma with the bulk target. In this paper, we present a continuous and efficient Mo K-alpha x-ray source produced by a femtosecond laser system operating at 100 Hz repetition rate with maximum pulse energy of 110 mJ before compression. The source has an x-ray conversion efficiency of greater than 10−5 into K-alpha line emission. In preparation for phase contrast imaging applications, the size of the resultant K-alpha x-ray emission spot has been also characterized. The source exhibits sufficient spatial coherence to observe phase contrast. We observe a relatively small broadening of the K-alpha source size compared to the size of the laser beam itself. Detailed characterization of the source including the x-ray spectrum and the x-ray average yield along with phase contrast images of test objects will be presented. PMID:20046807

  9. Compact High Power THz Source

    SciTech Connect

    Geoffrey Krafft

    2003-08-01

    In this paper a new type of THz radiation source, based on recirculating an electron beam through a high gradient superconducting radio frequency cavity, and using this beam to drive a standard electromagnetic undulator, is discussed. Because the beam is recirculated, short bunches may be produced that radiate coherently in the undulator, yielding high average THz power for relatively low average beam power. Deceleration from the coherent emission, and the detuning it causes is discussed.

  10. Search for the Identification of 3EG J1835+5918: Evidence for a New Type of High-Energy Gamma-Ray Source

    NASA Technical Reports Server (NTRS)

    Mirabal, N.; Halpern, Jules P.; Eracleous, M.; Becker, R. H.; Oliversen, Ronald (Technical Monitor)

    2001-01-01

    The EGRET source 3EG J1835+5918 is the brightest and most accurately positioned of the as-yet unidentified high-energy gamma-ray sources at high Galactic latitude (l, b = 89 deg, 25 deg). We present a multiwavelength study of the region around it, including X-ray, radio, and optical imaging surveys, as well as optical spectroscopic classification of most of the active objects in this area. Identifications are made of all but one of the ROSAT and ASCA sources in this region to a flux limit of approximately 5 x 10(exp -14) erg/sq cm s, which is 10(exp -4) of the gamma-ray flux. The identified X-ray sources in or near the EGRET error ellipse are radio-quiet QSOs, a galaxy cluster, and coronal emitting stars. We also find eight quasars using purely optical color selection, and we have monitored the entire field for variable optical objects on short and long time scales without any notable discoveries. The radio sources inside the error ellipse are all fainter than 4 mJy at 1.4 GHz. There are no flat-spectrum radio sources in the vicinity; the brightest neighboring radio sources are steep-spectrum radio galaxies or quasars. Since no blazar-like or pulsar-like candidate has been found as a result of these searches, 3EG J1835+5918 must be lacking one or more of the physically essential attributes of these known classes of gamma-ray emitters. If it is an AGN it lacks the beamed emission radio of blazars by at least a factor of 100 relative to identified EGRET blazars. If it is an isolated neutron star, it lacks the steady thermal X-rays from a cooling surface and the magnetospheric non-thermal X-ray emission that is characteristic of all EGRET pulsars. If a pulsar, 3EG J1835+5918 must be either older or more distant than Geminga, and probably an even more efficient or beamed gamma-ray engine. One intermittent ROSA T source falls on a blank optical field to a limit of B greater than 23.4, V greater than 23.3, and R greater than 22.5. In view of this conspicuous absence, RX

  11. A Proposal to the Department of Energy for The Fabrication of a Very High Energy Polarized Gama Ray Beam Facility and A Program of Medium Energy Physics Research at The National Synchrotron Light Source

    SciTech Connect

    Sandorfi, A.M.; LeVine, M.J.; Thorn, C.E.; Giordano, G.; Matone, G.

    1982-09-01

    This proposal requests support for the fabrication and operation of a modest facility that would provide relatively intense beams of monochromatic and polarized photons with energies in the range of several hundreds of MeV. These {gamma} rays would be produced by Compton backscattering laser light from the electrons circulating in the 2.5-3.0 GeV 'X-RAY' storage ring of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The excellent emittance, phase space, and high current of this state-of-the-art storage ring will allow the production of 2 x 10{sup 7} {gamma} rays per second. These photons would be tagged by detecting the scattered electrons, thereby determining the energy to 2.7 MeV for all {gamma}-ray energies. The efficiency of this tagging procedure is 100% and the {gamma}-ray beam would be essentially background free. Tagging will also allow the flexibility of operating with a dynamic range as large as 200 MeV in photon energy while still preserving high resolution and polarization. These beams will permit a fruitful study of important questions in medium-energy nuclear physics. The initial goals of this program are to reach reliable operation with photon energies up to 300 MeV and to develop {gamma}-ray beams with energies up to about 500 MeV. To demonstrate reliable operation, a modest physics program is planned that, for the most part, utilizes existing magnets and detector systems but nonetheless addresses several important outstanding problems. Gamma ray beams of the versatility, intensity, energy, and resolution that can be achieved at this facility are not currently available at any other world facility either existing or under construction. Furthermore, the proposed program would produce the first intense source of medium-energy {gamma} rays that are polarized. Because of the difficulties in producing such polarized beams, it is very unlikely that viable alternate sources can be developed in the near future; at present

  12. Development of a compact electron-cyclotron-resonance ion source for high-energy carbon-ion therapy

    NASA Astrophysics Data System (ADS)

    Muramatsu, M.; Kitagawa, A.; Sakamoto, Y.; Sato, S.; Sato, Y.; Ogawa, Hirotsugu; Yamada, S.; Ogawa, Hiroyuki; Yoshida, Y.; Drentje, A. G.

    2005-11-01

    Ion sources for medical facilities should have characteristics of easy maintenance, low electric power consumption, good stability, and long operation time without problems (one year or longer). For this, a 10GHz compact electron-cyclotron-resonance ion source with all-permanent magnets (Kei2 source) was developed. The maximum mirror magnetic fields on the beam axis are 0.59T at the extraction side and 0.87T at the gas-injection side, while the minimum B strength is 0.25T. These parameters have been optimized for the production of C4+ based on the experience at the 10GHz NIRS-ECR ion source and a previous prototype compact source (Kei source). The Kei2 source has a diameter of 320mm and a length of 295mm. The beam intensity of C4+ was obtained to be 530μA under an extraction voltage of 40kV. The beam stability was better than 6% at C4+ of 280μA during 90h with no adjustment of the operation parameters. The details of the design and beam tests of the source are described in this paper.

  13. Cavity as a Source of Conformational Fluctuation and High-Energy State: High-Pressure NMR Study of a Cavity-Enlarged Mutant of T4Lysozyme

    PubMed Central

    Maeno, Akihiro; Sindhikara, Daniel; Hirata, Fumio; Otten, Renee; Dahlquist, Frederick W.; Yokoyama, Shigeyuki; Akasaka, Kazuyuki; Mulder, Frans A.A.; Kitahara, Ryo

    2015-01-01

    Although the structure, function, conformational dynamics, and controlled thermodynamics of proteins are manifested by their corresponding amino acid sequences, the natural rules for molecular design and their corresponding interplay remain obscure. In this study, we focused on the role of internal cavities of proteins in conformational dynamics. We investigated the pressure-induced responses from the cavity-enlarged L99A mutant of T4 lysozyme, using high-pressure NMR spectroscopy. The signal intensities of the methyl groups in the 1H/13C heteronuclear single quantum correlation spectra, particularly those around the enlarged cavity, decreased with the increasing pressure, and disappeared at 200 MPa, without the appearance of new resonances, thus indicating the presence of heterogeneous conformations around the cavity within the ground state ensemble. Above 200 MPa, the signal intensities of >20 methyl groups gradually decreased with the increasing pressure, without the appearance of new resonances. Interestingly, these residues closely matched those sensing a large conformational change between the ground- and high-energy states, at atmospheric pressure. 13C and 1H NMR line-shape simulations showed that the pressure-induced loss in the peak intensity could be explained by the increase in the high-energy state population. In this high-energy state, the aromatic side chain of F114 gets flipped into the enlarged cavity. The accommodation of the phenylalanine ring into the efficiently packed cavity may decrease the partial molar volume of the high-energy state, relative to the ground state. We suggest that the enlarged cavity is involved in the conformational transition to high-energy states and in the volume fluctuation of the ground state. PMID:25564860

  14. Hybrid energy sources for embedded sensor nodes

    NASA Astrophysics Data System (ADS)

    Silva, Ramon; Farinholt, Kevin; Park, Gyuhae

    2011-04-01

    In this paper, we present a series of hybrid energy configurations that are designed to provide a robust power source for embedded sensing hardware. The proper management of energy resources is a critical component in the design of any deployed sensing network. For systems that are installed in remote or inaccessible locations, or those with an operational lifespan that exceeds traditional battery technologies, energy harvesting is an attractive alternative. Unfortunately, the dependence on a single energy source (i.e. solar) can cause potential problems when environmental conditions preclude the system from operating at peak performance. In this paper we consider the use of a hybrid energy source that extracts energy from multiple sources and uses this collective energy to power sensing hardware. The sources considered in this work include: solar, vibration, thermal gradients, and RF energy capture. Methods of increasing the efficiency, energy storage medium, target applications and the integrated use of energy harvesting sources with wireless energy transmission will be discussed.

  15. A new method of observing weak extended x-ray sources with the Reuven Ramaty high-energy solar spectroscopic imager.

    PubMed

    Hannah, Iain G; Hurford, Gordon J; Hudson, Hugh S; Lin, Robert P

    2007-02-01

    We present a new method, fan-beam modulation, for observing weak extended x-ray sources with the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). This space-based solar x-ray and gamma-ray telescope has much greater sensitivity than previous experiments in the 3-25 keV range, but is normally not well suited to detecting extended sources since their signal is not modulated by RHESSI's rotating grids. When the spacecraft is offpointed from the target source, however, the fan-beam modulation time-modulates the transmission by shadowing resulting from exploiting the finite thickness of the grids. In this article we detail how the technique is implemented and verify its consistency with sources with clear known signals that have occurred during RHESSI offpointing: microflares and the Crab Nebula. In both cases the results are consistent with previous and complementary measurements. Preliminary work indicates that this new technique allows RHESSI to observe the integrated hard x-ray spectrum of weak extended sources on the quiet Sun. PMID:17578130

  16. Fermi LAT detection of a new high-energy transient gamma-ray source Fermi J0751-5136

    NASA Astrophysics Data System (ADS)

    Kocevski, D.; Buson, S.

    2016-08-01

    During the week from 18 July through 25 July, 2016, the Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, observed gamma-ray activity from a previously unidentified transient source.

  17. Energy dispersive X-ray diffraction in the diamond anvil, high-pressure apparatus - Comparison of synchrotron and conventional X-ray sources

    NASA Technical Reports Server (NTRS)

    Spain, I. L.; Black, D. R.

    1985-01-01

    The use of both conventional fixed-anode X-ray sources and synchrotron radiation to carry out energy-dispersive X-ray diffraction experiments at high pressure in a diamond anvil cell, is discussed. The photon flux at the sample and at the detector for the two cases are compared and the results are presented in graphs. It is shown that synchrotron radiation experiments can be performed with nearly two orders of magnitude increase in data rate if superior detectors and detector electronics are available.

  18. High power microwave source development

    NASA Astrophysics Data System (ADS)

    Benford, James N.; Miller, Gabriel; Potter, Seth; Ashby, Steve; Smith, Richard R.

    1995-05-01

    The requirements of this project have been to: (1) improve and expand the sources available in the facility for testing purposes and (2) perform specific tasks under direction of the Defense Nuclear Agency about the applications of high power microwaves (HPM). In this project the HPM application was power beaming. The requirements of this program were met in the following way: (1) We demonstrated that a compact linear induction accelerator can drive HPM sources at repetition rates in excess of 100 HZ at peak microwave powers of a GW. This was done for the relativistic magnetron. Since the conclusion of this contract such specifications have also been demonstrated for the relativistic klystron under Ballistic Missile Defense Organization funding. (2) We demonstrated an L band relativistic magnetron. This device has been used both on our single pulse machines, CAMEL and CAMEL X, and the repetitive system CLIA. (3) We demonstrated that phase locking of sources together in large numbers is a feasible technology and showed the generation of multigigawatt S-band radiation in an array of relativistic magnetrons.

  19. Development of a low-energy and high-current pulsed neutral beam injector with a washer-gun plasma source for high-beta plasma experiments.

    PubMed

    Ii, Toru; Gi, Keii; Umezawa, Toshiyuki; Asai, Tomohiko; Inomoto, Michiaki; Ono, Yasushi

    2012-08-01

    We have developed a novel and economical neutral-beam injection system by employing a washer-gun plasma source. It provides a low-cost and maintenance-free ion beam, thus eliminating the need for the filaments and water-cooling systems employed conventionally. In our primary experiments, the washer gun produced a source plasma with an electron temperature of approximately 5 eV and an electron density of 5 × 10(17) m(-3), i.e., conditions suitable for ion-beam extraction. The dependence of the extracted beam current on the acceleration voltage is consistent with space-charge current limitation, because the observed current density is almost proportional to the 3/2 power of the acceleration voltage below approximately 8 kV. By optimizing plasma formation, we successfully achieved beam extraction of up to 40 A at 15 kV and a pulse length in excess of 0.25 ms. Its low-voltage and high-current pulsed-beam properties enable us to apply this high-power neutral beam injection into a high-beta compact torus plasma characterized by a low magnetic field. PMID:22938291

  20. Development of a low-energy and high-current pulsed neutral beam injector with a washer-gun plasma source for high-beta plasma experiments

    NASA Astrophysics Data System (ADS)

    Ii, Toru; Gi, Keii; Umezawa, Toshiyuki; Asai, Tomohiko; Inomoto, Michiaki; Ono, Yasushi

    2012-08-01

    We have developed a novel and economical neutral-beam injection system by employing a washer-gun plasma source. It provides a low-cost and maintenance-free ion beam, thus eliminating the need for the filaments and water-cooling systems employed conventionally. In our primary experiments, the washer gun produced a source plasma with an electron temperature of approximately 5 eV and an electron density of 5 × 1017 m-3, i.e., conditions suitable for ion-beam extraction. The dependence of the extracted beam current on the acceleration voltage is consistent with space-charge current limitation, because the observed current density is almost proportional to the 3/2 power of the acceleration voltage below approximately 8 kV. By optimizing plasma formation, we successfully achieved beam extraction of up to 40 A at 15 kV and a pulse length in excess of 0.25 ms. Its low-voltage and high-current pulsed-beam properties enable us to apply this high-power neutral beam injection into a high-beta compact torus plasma characterized by a low magnetic field.

  1. XMM-Newton Observations Reveal the X-ray Counterpart of the Very-high-energy gamma-ray Source HESS J1640-465

    SciTech Connect

    Funk, S.; Hinton, J.A.; Puhlhofer, G.; Aharonian, F.A.; Hofmann, W.; Reimer, O.; Wagner, S.; Funk, S.; Hinton, J.A.; Puehlhofer, G.; Aharonian, F.A.; Hofmann, W.; Reimer, O.; Wagner, S.

    2007-03-05

    We present X-ray observations of the as of yet unidentified very high-energy (VHE) {gamma}-ray source HESS J1640-465 with the aim of establishing a counterpart of this source in the keV energy range, and identifying the mechanism responsible for the VHE emission. The 21.8 ksec XMM-Newton observation of HESS J1640-465 in September 2005 represents a significant improvement in sensitivity and angular resolution over previous ASCA studies in this region. These new data show a hard-spectrum X-ray emitting object at the centroid of the H.E.S.S. source, within the shell of the radio Supernova Remnant (SNR) G338.3-0.0. This object is consistent with the position and flux previously measured by both ASCA and Swift-XRT but is now shown to be significantly extended. We argue that this object is very likely the counterpart to HESS J1640-465 and that both objects may represent the Pulsar Wind Nebula of an as of yet undiscovered pulsar associated with G338.3-0.0.

  2. Testing of two source energy balance model under irrigated and dryland conditions using high resolution airborne imagery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two Source Model (TSM) calculates the heat and water exchange and interaction between soil-atmosphere and vegetation-atmosphere separately. This is achieved through decomposition of radiometric surface temperature to soil and vegetation component temperatures either from multi-angular remotely sense...

  3. A new method of testing space-based high-energy electron detectors with radioactive electron sources

    NASA Astrophysics Data System (ADS)

    Zhang, S. Y.; Shen, G. H.; Sun, Y.; Zhou, D. Z.; Zhang, X. X.; Li, J. W.; Huang, C.; Zhang, X. G.; Dong, Y. J.; Zhang, W. J.; Zhang, B. Q.; Shi, C. Y.

    2016-05-01

    Space-based electron detectors are commonly tested using radioactive β-sources which emit a continuous spectrum without spectral lines. Therefore, the tests are often to be considered only qualitative. This paper introduces a method, which results in more than a qualitative test even when using a β-source. The basic idea is to use the simulated response function of the instrument to invert the measured spectrum and compare this inverted spectrum with a reference spectrum obtained from the same source. Here we have used Geant4 to simulate the instrument response function (IRF) and a 3.5 mm thick Li-drifted Si detector to obtain the reference 90Sr/90Yi source spectrum to test and verify the geometric factors of the Omni-Direction Particle Detector (ODPD) on the Tiangong-1 (TG-1) and Tiangong-2 (TG-2) spacecraft. The TG spacecraft are experimental space laboratories and prototypes of the Chinese space station. The excellent agreement between the measured and reference spectra demonstrates that this test method can be used to quantitatively assess the quality of the instrument. Due to its simplicity, the method is faster and therefore more efficient than traditional full calibrations using an electron accelerator.

  4. Development of liquid-metal-ion source low-energy ion gun/high-temperature ultrahigh vacuum scanning tunneling microscope combined system

    SciTech Connect

    Uchigasaki, M.; Kamioka, T.; Hirata, T.; Shimizu, T.; Lin, F.; Shinada, T.; Ohdomari, I.

    2005-12-15

    A liquid-metal-ion source low-energy ion gun/high-temperature ultrahigh vacuum scanning tunneling microscope combined system (LMIS-IG/STM) has been developed in order to investigate the ion beam modification process in situ based on our previous ion gun/STM combined system (IG/STM). Various kinds of metal ions can be irradiated with low acceleration energy of 0.01-5 keV during STM observation at 400-600 deg. C. As an example, real-time STM observation of Si(111)7x7 surface irradiated with Si{sup 2+} ions is demonstrated. The STM results have shown that the surface defects generated by Si{sup 2+} ion irradiation exhibit similar behavior of surface defects induced by Ar{sup +} irradiation with IG/STM.

  5. Energy Recovery Linacs for Light Source Applications

    SciTech Connect

    George Neil

    2011-04-01

    Energy Recovery Linacs are being considered for applications in present and future light sources. ERLs take advantage of the continuous operation of superconducting rf cavities to accelerate high average current beams with low losses. The electrons can be directed through bends, undulators, and wigglers for high brightness x ray production. They are then decelerated to low energy, recovering power so as to minimize the required rf drive and electrical draw. When this approach is coupled with advanced continuous wave injectors, very high power, ultra-short electron pulse trains of very high brightness can be achieved. This paper will review the status of worldwide programs and discuss the technology challenges to provide such beams for photon production.

  6. Supplementing Conservation Practices with Alternative Energy Sources.

    ERIC Educational Resources Information Center

    Kraetsch, Gayla A.

    1981-01-01

    Universities and colleges have two major roles: to reduce their own energy consumption and costs, and to develop and test new energy options. Alternative energy sources considered include solar energy, wind power, biomass, hydropower, ocean energy, geothermal heat, coal, and nuclear energy. (MLW)

  7. High-brightness multilaser source

    NASA Astrophysics Data System (ADS)

    Goodman, Douglas S.; Gordon, Wayne L.; Jollay, Richard A.; Roblee, Jeffrey W.; Gavrilovic, Paul; Kuksenkov, Dmitri V.; Goyal, Anish K.; Zu, Qinxin

    1999-04-01

    This paper discusses a high-brightness multi-laser source developed at Polaroid for such applications as coupling light to fibers, pumping fiber lasers, pumping solid state lasers, material processing, and medical procedures. The power and brightness are obtained by imaging the nearfields of up to eight separate multi-mode lasers side by side on a multi-faceted mirror that makes the beams parallel. The lasers are microlensed to equalize the divergences in the two principal meridians. Each laser is aligned in a field- replaceable illuminator module whose output beam, focused at infinity, is bore-sighted in a mechanical cylinder. The illuminators are arranged roughly radially and the nearfields are reimaged on the mirror, which is produced by diamond machining. The array of nearfields is linearly polarized. A customizable afocal relay forms a telecentric image of the juxtaposed nearfields, as required by the application. The lasers can be of differing powers and wavelengths, and they can be independently switched. Light from other sources can be combined. The output can be utilized in free space or it can be coupled into a fiber for transport or a fiber laser for pumping. A linearly polarized free space output can be obtained, which allows two units to be polarization combined to double the power and brightness.

  8. Search for the Identification of 3EG J1835+5918: Evidence for a New Type of High-Energy Gamma-Ray Source?

    NASA Technical Reports Server (NTRS)

    Mirabal, N.; Halpern, Jules P.; Eracleous, M.; Becker, R. H.; Oliversen, Ronald (Technical Monitor)

    2001-01-01

    Most of the EGRET high-energy gamma-ray sources remain unidentified. It is highly likely that many of these are fainter blazars or pulsars, but there may also be new types of sources to be discovered. We have focussed our search for novel gamma-ray sources on 3EG 1835+5918, which is the brightest and most accurately positioned of the unidentified EGRET sources at high Galactic latitude (l, b = 89 deg, 25 deg). In this talk, we will summarize the results of X-ray, radio, and optical surveys of this location. In particular, we have made complete optical identifications of all of the ROSAT and ASCA sources in this region to a flux limit of approximately 1 x 10(exp -13) ergs/sq cm s. All of the X-ray sources within the EGRET error circle are radio-quiet quasars or coronally emitting stars. Previous radio pulsar searches have been unsuccessful. We set an upper limit of 3.8 mJy (at 1.4 GHz) on any possible radio counterpart to 3EG 1835+5918. We also find several quasars and white dwarfs using optical color selection, and we have monitored the entire field for variable optical objects on short and long time scales. Since no blazar-like or pulsar-like candidate has been found as a result of these searches, we assert that 3EG 1835+5918 must be lacking in one or more of the physically essential attributes of those classes of gamma-ray emitters. In particular, its radio flux is at least two orders of magnitude fainter than any of the securely identified EGRET blazars, and its soft X-ray flux is at least 30 times fainter than that of Geminga and other EGRET pulsars. If it is an AGN it lacks the beamed radio emission of blazars. If it is an isolated neutron star, it lacks both the thermal X-rays from a cooling surface and the magnetospheric non-thermal X-ray emission that is characteristic of all EGRET pulsars. As such, it is more problematic physically than Geminga, which is an ordinary pulsar that only lacks radio emission. As a pulsar, 3EG 1835+5918 would have to be either

  9. MASTER OT J130845.02-323254.9: Variable Stars as Source of the High Energy Neutrino.

    NASA Astrophysics Data System (ADS)

    Lipunov, V.; Tyurina, N.; Gorbovskoy, E.; Buckley, D.

    2016-09-01

    As reported in ATel #9425 Global MASTER Net auto-detection system ( ( Lipunov et al., MASTER Global Robotic Net, Advances in Astronomy, 2010, 30L) discovered OT source at (RA, Dec) = 13h 08m 45.02s -32d 32m 54.9s on 2016-08-24.73811 UT during inspection of HESE IceCube alert (14 August 2016, 58537957 trigger number http://gcn.gsfc.nasa.gov/notices_amon/58537957_128340.amon , Dornic et al. ATEL #9440 ). MASTER-SAAO auto-detection system detected again OT at RA (2000) = 13 08 45.02 -32 32 54.9 on 2016-09-04.7627UT (ATEL #9425).

  10. Conservation as an alternative energy source

    NASA Technical Reports Server (NTRS)

    Allen, D. E.

    1978-01-01

    A speech is given outlining the energy situation in the United States. It is warned that the existing energy situation cannot prevail and the time is fast running out for continued growth or even maintenance of present levels. Energy conservation measures are given as an aid to decrease U.S. energy consumption, which would allow more time to develop alternative sources of energy.

  11. Fusion: an energy source for synthetic fuels

    SciTech Connect

    Fillo, J A; Powell, J; Steinberg, M

    1980-01-01

    The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. 40 to 60% and hydrogen production efficiencies by high temperature electrolysis of approx. 50 to 70% are projected for fusion reactors using high temperature blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long term, there could be a gradual transition to an inexhaustible energy system based solely on fusion.

  12. Observations of celestial X-ray sources above 20 keV with the high-energy scintillation spectrometer on board OSO 8

    NASA Technical Reports Server (NTRS)

    Crannell, C. J.; Dennis, B. R.; Dolan, J. H.; Frost, K. J.; Orwig, L. E.; Beall, J. H.; Maurer, G. S.

    1977-01-01

    High-energy X-ray spectra of the Crab Nebula, Cyg- XR-1, and Cen A were determined from observations with the scintillation spectrometer on board the OSO-8 satellite, launched in June, 1975. Each of these sources was observed over two periods of 8 days or more, enabling a search for day-to-day and year to year variations in the spectral and temporal characteristics of the X-ray emission. No variation in the light curve of the Crab pulsar was found from observations which span a 15-day period in March 1976, with demonstrable phase stability. Transitions associated with the binary phase of Cyg XR-1 and a large change in the emission from Con A are reported.

  13. The X-ray behaviour of the high-energy peaked BL Lacertae source PKS 2155-304 in the 0.3-10 keV band

    NASA Astrophysics Data System (ADS)

    Kapanadze, B.; Romano, P.; Vercellone, S.; Kapanadze, S.

    2014-10-01

    We present the results of our monitoring of the high-energy peaked BL Lac object PKS 2155-304 by the Swift/X-Ray Telescope (XRT) during 2005-2012. Our timing study shows that the source was highly variable both on longer (weeks-to-months) and intra-day time-scales, up to a factor of 7 in flux, and 30 per cent in fractional variability amplitudes, with no periodic variations. The X-ray spectra are mainly curved with broad ranges of photon index, curvature parameter, and hardness ratio which exhibit significant variability with the flux on different time-scales. Our study of multi-wavelength cross-correlations has revealed that the one-zone SSC scenario seems to be valid for the most optical-to-gamma-ray flares observed during 2006-2012. An `orphan' X-ray flare with no counterpart in other spectral bands suggests the existence of different electron populations. Based on the absence of a correlation between photon index and curvature parameter (expected from the energy-dependent acceleration probability scenario), the observed distribution of curvature parameter from the XRT spectra peaking at b = 0.37, and the observed anti-correlation between the curvature parameter and the 0.3-10 keV flux (i.e. lower curvatures in flaring states), we conclude that the most likely mechanism responsible for producing X-ray emission during the flares is the stochastic acceleration of the electrons.

  14. HIGH-INTENSITY, HIGH CHARGE-STATE HEAVY ION SOURCES

    SciTech Connect

    ALESSI,J.G.

    2004-08-16

    There are many accelerator applications for high intensity heavy ion sources, with recent needs including dc beams for RIA, and pulsed beams for injection into synchrotrons such as RHIC and LHC. The present status of sources producing high currents of high charge state heavy ions is reviewed. These sources include ECR, EBIS, and Laser ion sources. Benefits and limitations for these type sources are described. Possible future improvements in these sources are also mentioned.

  15. Power conditioning system for energy sources

    SciTech Connect

    Mazumder, Sudip K.; Burra, Rajni K.; Acharya, Kaustuva

    2008-05-13

    Apparatus for conditioning power generated by an energy source includes an inverter for converting a DC input voltage from the energy source to a square wave AC output voltage, and a converter for converting the AC output voltage from the inverter to a sine wave AC output voltage.

  16. Biochar As a Renewable Energy Source

    NASA Astrophysics Data System (ADS)

    Stein, Richard

    2011-11-01

    Biochar is a form of charcoal prepared by heating biomass in limited air. It is porous and has high surface area, maintaining much of the morphology of the biomass. The heat for its preparation arises primarily from burning volatiles emitted upon heating. About half the chemical energy in the biomass is contained in the biochar, about 40% is used for the conversion, and about 10% may be used as a local heat source. The biochar can serve as a soil additive where it acts as a template for the growth of bacteria and fungi which then lead to improved growth of biomass by as much as several hundred percent. It remains inert in the soil for many years. Thus, it sequesters the carbon, originally coming from the carbon dioxide absorbed during the photosynthesis occurring during the growth of the biomass. Its use reduces fertilizer and water needs and to pollution arising from the run-off of fertilizer and emission of noxious vapors. Its use is best done at a local level, close to sources of biomass from farm and forest waste. The Pioneer Valley Biochar Initiative along with the Center of Agriculture of the University of Massachusetts, Amherst is promoting the use of biochar on local farms which reduces their dependence on energy arising from fossil fuel and nuclear sources.

  17. High power millimeter wave source development program

    NASA Technical Reports Server (NTRS)

    George, T. V.

    1989-01-01

    High power millimeter wave sources for fusion program; ECH source development program strategy; and 1 MW, 140 GHz gyrotron experiment design philosophy are briefly outlined. This presentation is represented by viewgraphs only.

  18. Phase development during high-energy ball-milling of zinc oxide and iron - the impact of grain size on the source and the degree of contamination.

    PubMed

    Štefanić, G; Krehula, S; Štefanić, I

    2015-11-21

    High-energy ball-milling of powder mixtures of zincite (ZnO) and iron (α-Fe) at different weight ratios was performed in air using a planetary ball mill with a stainless steel milling assembly. Structural and microstructural changes during the ball-milling (up to 30 h) were monitored using X-ray powder diffraction, field emission scanning electron microscopy (FE-SEM) and UV-Vis diffuse reflectance spectroscopy. The mechanism of iron oxidation was determined from the results of Mössbauer spectroscopy. It was found that an early phase of ball-milling caused the oxidation of iron from Fe(0) to Fe(2+) followed by the formation of a solid solution structurally similar to wüstite. The wüstite-type phase rapidly disappeared upon prolonged milling, which was accompanied by further oxidation of iron from Fe(2+) to Fe(3+) and the formation of spinel-type ferrite structurally similar to franklinite (ZnFe2O4) in the products with a high zinc content, or magnetite (Fe3O4) in the products with a high iron content. Further milling or annealing had a low impact on the franklinite-type phase, but caused the transition of the magnetite-type phase to the phase structurally similar to hematite (α-Fe2O3). The results of energy dispersive X-ray spectrometry (EDS) showed a dramatic increase in the degree of contamination with the increase in the proportion of the starting iron (∼9 times higher contamination during the milling of pure iron compared with pure zincite). It was shown that the source of contamination (balls or vial) strongly depends on the type of milled sample. Ball-milling of relatively big and heavy grains (starting iron) caused preferential contamination from the vial whereas ball-milling of smaller and lighter grains (products obtained after prolonged milling) caused preferential contamination from the balls. After prolonged milling the contamination due to wear of the balls was dominant in all the products. An explanation for the observed impact of grain size on

  19. Pomegranate-Structured Conversion-Reaction Cathode with a Built-in Li Source for High-Energy Li-Ion Batteries.

    PubMed

    Fan, Xiulin; Zhu, Yujie; Luo, Chao; Suo, Liumin; Lin, Yan; Gao, Tao; Xu, Kang; Wang, Chunsheng

    2016-05-24

    Transition metal fluorides (such as FeF3 or CoF2) promise significantly higher theoretical capacities (>571 mAh g(-1)) than the cathode materials currently used in Li-ion batteries. However, their practical application faces major challenges that include poor electrochemical reversibility induced by the repeated bond-breaking and formation and the accompanied volume changes and the difficulty of building an internal Li source within the material so that a full Li-ion cell could be assembled at a discharged state without inducing further technical risk and cost issues. In this work, we effectively addressed these challenges by designing and synthesizing, via an aerosol-spray pyrolysis technique, a pomegranate-structured nanocomposite FeM/LiF/C (M = Co, Ni), in which 2-3 nm carbon-coated FeM nanoparticles (∼10 nm in diameter) and LiF nanoparticles (∼20 nm) are uniformly embedded in a porous carbon sphere matrix (100-1000 nm). This uniquely architectured nanocomposite was made possible by the extremely short pyrolysis time (∼1 s) and carbon coating in a high-temperature furnace, which prevented the overgrowth of FeM and LiF in the primordial droplet that serves as the carbon source. The presence of Ni or Co in FeM/LiF/C effectively suppresses the formation of Fe3C and further reduces the metallic particle size. The pomegranate architecture ensures the intimate contact among FeM, LiF, and C, thus significantly enhancing the conversion-reaction kinetics, while the nanopores inside the pomegranate-like carbon matrix, left by solvent evaporation during the pyrolysis, effectively accommodate the volume change of FeM/LiF during charge/discharge. Thus, the FeM/LiF/C nanocomposite shows a high specific capacity of >300 mAh g(-1) for more than 100 charge/discharge cycles, which is one of the best performances among all of the prelithiated metal fluoride cathodes ever reported. The pomegranate-structured FeM/LiF/C with its built-in Li source provides an inspiration to the

  20. High Power Polarized Positron Source

    NASA Astrophysics Data System (ADS)

    Mikhailichenko, Alexander

    2009-09-01

    We discuss the basics of polarized positron production by low energy polarized electrons. Efficiency of conversion ˜0.1-1% might be interesting for the Continuous Electron Beam Accelerator Facility (CEBAF) and the International Linear Collider (ILC).

  1. Delays in Tapping Energy Sources

    ERIC Educational Resources Information Center

    Abelson, Philip H.

    1975-01-01

    Summarizes factors that will create severe energy shortages by 1980. Indicates that conservation is not enough, and the quickest path toward relief is the expansion of surface mining of low-sulfur coal in the Rocky Mountain states. (GS)

  2. Sugar cane. Positive energy source for alcohol

    SciTech Connect

    Polack, J.A.; Birkett, H.S.; West, M.D.

    1981-06-01

    Sugar cane stands out as a renewable resource for fuel alcohol production, thanks to its unique, highly positive energy balance. It supplies its own processing fuel, bagasse. Net liquid fuel usage is only that consumed on the farm, amounting to a maximum of 0.3 volume per volume of ethanol produced. In some locations, the net liquid fuel consumption of the farm is as low as 0.12 volume/volume produced. This small debit may be offset by generating electric power and by foreseeable processing improvements. In view of the very favorable fuel balance for sugar cane, a decision to employ it as a renewable source of ethanol depends wholly on economic and political factors, which in turn are highly location-dependent.

  3. Renewable energy sources 1991, part 2

    NASA Astrophysics Data System (ADS)

    Michalicka, L.

    1991-12-01

    The International Conference on Renewable Energy Sources was held in Prague on 1-4 Jul. 1991. Part 2 of the proceedings is devoted to the use of the energy of wind, biogas, and small hydroelectric sources. The publication contains 14 contributions, of which 3 were inputted in INIS. Topics covered include: a wind power plant in Sweden and its environmental impacts, economic aspects of the introduction of alternative energy sources in Czechoslovakia, and the efficiency of application of a Fresnel lens-based solar collector.

  4. ENERGY CONSERVATION THROUGH SOURCE REDUCTION

    EPA Science Inventory

    This report deals with energy conservation through reduction in generation of post-consumer solid waste. The objective, scope, methodology and summary of the report are presented in Section 1. Section 2 contains the conclusions. Section 3 presents a review of output and input app...

  5. Estimation of water and energy fluxes over complex landscapes. Two Source Energy Balance modelling using very high resolution thermal and optical imagery in vineyards and wooded rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modelling the water and energy balance at the land surface is a crucial task for many applications related to crop production, water resources management, climate change studies, weather forecasting, and natural hazards assessment. To improve the modelling of evapotranspiration (ET) over structurall...

  6. High pulse power rf sources for linear colliders

    SciTech Connect

    Wilson, P.B.

    1983-09-01

    RF sources with high peak power output and relatively short pulse lengths will be required for future high gradient e/sup +/e/sup -/ linear colliders. The required peak power and pulse length depend on the operating frequency, energy gradient and geometry of the collider linac structure. The frequency and gradient are in turn constrained by various parameters which depend on the beam-beam collision dynamics, and on the total ac wall-plug power that has been committed to the linac rf system. Various rf sources which might meet these requirements are reviewed. Existing source types (e.g., klystrons, gyrotrons) and sources which show future promise based on experimental prototypes are first considered. Finally, several proposals for high peak power rf sources based on unconventional concepts are discussed. These are an FEL source (two beam accelerator), rf energy storage cavities with switching, and a photocathode device which produces an rf current by direct emission modulation of the cathode.

  7. ALTERNATIVE ENERGY SOURCES FOR WASTEWATER TREATMENT PLANTS

    EPA Science Inventory

    The technology assessment provides an introduction to the use of several alternative energy sources at wastewater treatment plants. The report contains fact sheets (technical descriptions) and data sheets (cost and design information) for the technologies. Cost figures and schema...

  8. In situ observation of formation and growth of oxygen nano-precipitates in silicon with high energy X-rays from a laboratory source

    NASA Astrophysics Data System (ADS)

    Grillenberger, H.; Knerer, D.; Magerl, A.

    2011-03-01

    A focusing Laue diffractometer is used to analyze the strain field in silicon in situ during different thermal treatments up to 1000 °C. A high energy X-ray tube is the source for this so-called strain field diffraction (SFD) setup. The SFD setup is utilized to monitor in situ the strain generated by growing oxygen precipitates (bulk micro defects, BMD) in Czochralski grown silicon. Subsequently, the in situ investigated samples are characterized subsequently with ex situ techniques including FT-IR, infra red light scattering tomography (IR-LST) and TEM. By correlating enhancements of the integrated intensity (EII) of an investigated 220 silicon Bragg peak with BMD diameters obtained with TEM measurements a strong dependency of the total BMD volume and EII is found. The detection limit of the SFD setup is determined at a BMD diameter of 7 nm and a density of 1013 cm-3, and at 40 nm at a density of 108 cm-3. Thus SFD reaches into a detection range only covered by TEM so far and having additional advantages in in situ capability and minimal sample preparation requirements.

  9. High flux solar energy transformation

    DOEpatents

    Winston, Roland; Gleckman, Philip L.; O'Gallagher, Joseph J.

    1991-04-09

    Disclosed are multi-stage systems for high flux transformation of solar energy allowing for uniform solar intensification by a factor of 60,000 suns or more. Preferred systems employ a focusing mirror as a primary concentrative device and a non-imaging concentrator as a secondary concentrative device with concentrative capacities of primary and secondary stages selected to provide for net solar flux intensification of greater than 2000 over 95 percent of the concentration area. Systems of the invention are readily applied as energy sources for laser pumping and in other photothermal energy utilization processes.

  10. High flux solar energy transformation

    DOEpatents

    Winston, R.; Gleckman, P.L.; O'Gallagher, J.J.

    1991-04-09

    Disclosed are multi-stage systems for high flux transformation of solar energy allowing for uniform solar intensification by a factor of 60,000 suns or more. Preferred systems employ a focusing mirror as a primary concentrative device and a non-imaging concentrator as a secondary concentrative device with concentrative capacities of primary and secondary stages selected to provide for net solar flux intensification of greater than 2000 over 95 percent of the concentration area. Systems of the invention are readily applied as energy sources for laser pumping and in other photothermal energy utilization processes. 7 figures.

  11. Spallation neutron source and other high intensity froton sources

    SciTech Connect

    Weiren Chou

    2003-02-06

    This lecture is an introduction to the design of a spallation neutron source and other high intensity proton sources. It discusses two different approaches: linac-based and synchrotron-based. The requirements and design concepts of each approach are presented. The advantages and disadvantages are compared. A brief review of existing machines and those under construction and proposed is also given. An R&D program is included in an appendix.

  12. High stability wavefront reference source

    DOEpatents

    Feldman, M.; Mockler, D.J.

    1994-05-03

    A thermally and mechanically stable wavefront reference source which produces a collimated output laser beam is disclosed. The output beam comprises substantially planar reference wavefronts which are useful for aligning and testing optical interferometers. The invention receives coherent radiation from an input optical fiber, directs a diverging input beam of the coherent radiation to a beam folding mirror (to produce a reflected diverging beam), and collimates the reflected diverging beam using a collimating lens. In a class of preferred embodiments, the invention includes a thermally and mechanically stable frame comprising rod members connected between a front end plate and a back end plate. The beam folding mirror is mounted on the back end plate, and the collimating lens mounted to the rods between the end plates. The end plates and rods are preferably made of thermally stable metal alloy. Preferably, the input optical fiber is a single mode fiber coupled to an input end of a second single mode optical fiber that is wound around a mandrel fixedly attached to the frame of the apparatus. The output end of the second fiber is cleaved so as to be optically flat, so that the input beam emerging therefrom is a nearly perfect diverging spherical wave. 7 figures.

  13. High stability wavefront reference source

    DOEpatents

    Feldman, Mark; Mockler, Daniel J.

    1994-01-01

    A thermally and mechanically stable wavefront reference source which produces a collimated output laser beam. The output beam comprises substantially planar reference wavefronts which are useful for aligning and testing optical interferometers. The invention receives coherent radiation from an input optical fiber, directs a diverging input beam of the coherent radiation to a beam folding mirror (to produce a reflected diverging beam), and collimates the reflected diverging beam using a collimating lens. In a class of preferred embodiments, the invention includes a thermally and mechanically stable frame comprising rod members connected between a front end plate and a back end plate. The beam folding mirror is mounted on the back end plate, and the collimating lens mounted to the rods between the end plates. The end plates and rods are preferably made of thermally stable metal alloy. Preferably, the input optical fiber is a single mode fiber coupled to an input end of a second single mode optical fiber that is wound around a mandrel fixedly attached to the frame of the apparatus. The output end of the second fiber is cleaved so as to be optically flat, so that the input beam emerging therefrom is a nearly perfect diverging spherical wave.

  14. The JLab high power ERL light source

    SciTech Connect

    G.R. Neil; C. Behre; S.V. Benson; M. Bevins; G. Biallas; J. Boyce; J. Coleman; L.A. Dillon-Townes; D. Douglas; H.F. Dylla; R. Evans; A. Grippo; D. Gruber; J. Gubeli; D. Hardy; C. Hernandez-Garcia; K. Jordan; M.J. Kelley; L. Merminga; J. Mammosser; W. Moore; N. Nishimori; E. Pozdeyev; J. Preble; R. Rimmer; Michelle D. Shinn; T. Siggins; C. Tennant; R. Walker; G.P. Williams and S. Zhang

    2005-03-19

    A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz {approx} half cycle pulse whose average brightness is > 5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted[1]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [2]: up to 10 kW of average power in the IR from 1 to 14 microns in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 microseconds long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made

  15. The JLab high power ERL light source

    NASA Astrophysics Data System (ADS)

    Neil, G. R.; Behre, C.; Benson, S. V.; Bevins, M.; Biallas, G.; Boyce, J.; Coleman, J.; Dillon-Townes, L. A.; Douglas, D.; Dylla, H. F.; Evans, R.; Grippo, A.; Gruber, D.; Gubeli, J.; Hardy, D.; Hernandez-Garcia, C.; Jordan, K.; Kelley, M. J.; Merminga, L.; Mammosser, J.; Moore, W.; Nishimori, N.; Pozdeyev, E.; Preble, J.; Rimmer, R.; Shinn, M.; Siggins, T.; Tennant, C.; Walker, R.; Williams, G. P.; Zhang, S.

    2006-02-01

    A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz ˜ half cycle pulse whose average brightness is >5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted [Carr, et al., Nature 420 (2002) 153]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [Neil, et al., Phys. Rev. Lett. 84 (2000) 662]: up to 10 kW of average power in the IR from 1 to 14 μm in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 ms long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the

  16. Alpha Schottky junction energy source

    NASA Astrophysics Data System (ADS)

    Litz, Marc S.; Fan, Zhaoyang; Carroll, James J.; Bayne, Stephen

    2012-06-01

    Isotope batteries offer solutions for long-lived low-power sensor requirements. Alpha emitting isotopes have energy per decay 103 times that of beta emitters. Alpha particles are absorbed within 20 μm of most materials reducing shielding mitigation. However, damage to materials from the alphas limits their practical use. A Schottky Barrier Diode (SBD) geometry is considered with an alpha emitting contact-layer on a diamond-like crystal semiconductor region. The radiation tolerance of diamond, the safety of alpha particles, combined with the internal field of the SBD is expected to generate current useful for low-power electronic devices over decades. Device design parameters and calculations of the expected current are described.

  17. Very high power THz radiation sources

    SciTech Connect

    Carr, G.L.; Martin, Michael C.; McKinney, Wayne R.; Jordan, K.; Neil, George R.; Williams, G.P.

    2002-10-31

    We report the production of high power (20 watts average, {approx} 1 Megawatt peak) broadband THz light based on coherent emission from relativistic electrons. Such sources are ideal for imaging, for high power damage studies and for studies of non-linear phenomena in this spectral range. We describe the source, presenting theoretical calculations and their experimental verification. For clarity we compare this source to one based on ultrafast laser techniques.

  18. Risk with energy from conventional and nonconventional sources.

    PubMed

    Inhaber, H

    1979-02-23

    Risk to human health was compared for five conventional and six nonconventional energy systems. The entire cycle for producing energy was considered, not just part. The most important conclusion drawn is that the risk to human health from nonconventional sources can be as high as, or even higher than, that of conventional sources. This result is produced only when the risk per unit energy is considered, rather than the risk per solar panel or windmill. The risk from nonconventional energy sources derives from the large amount of material and labor needed, along with their backup and storage requirements. Risk evaluation is a relatively new discipline, and therefore the results presented here can be considered only a beginning. However, society should keep relative risk in mind when evaluating present and future energy sources. PMID:419404

  19. High power millimeter wave ECRH source needs for fusion program

    SciTech Connect

    Not Available

    1984-06-01

    This document stems from the four-day Gyrotron Symposium held at the US Department of Energy (DOE) Headquarters on June 13-16, 1983, and serves as a position paper for the Office of Fusion Energy, DOE, on high-power millimeter wave source development for Electron Cyclotron Heating (ECH) of plasmas. It describes the fusion program needs for gyrotron as ECH sources, their current status, and desirable development strategies.

  20. The Jefferson Lab High Power Light Source

    SciTech Connect

    James R. Boyce

    2006-01-01

    Jefferson Lab has designed, built and operated two high average power free-electron lasers (FEL) using superconducting RF (SRF) technology and energy recovery techniques. Between 1999-2001 Jefferson Lab operated the IR Demo FEL. This device produced over 2 kW in the mid-infrared, in addition to producing world record average powers in the visible (50 W), ultraviolet (10 W) and terahertz range (50 W) for tunable, short-pulse (< ps) light. This FEL was the first high power demonstration of an accelerator configuration that is being exploited for a number of new accelerator-driven light source facilities that are currently under design or construction. The driver accelerator for the IR Demo FEL uses an Energy Recovered Linac (ERL) configuration that improves the energy efficiency and lowers both the capital and operating cost of such devices by recovering most of the power in the spent electron beam after optical power is extracted from the beam. The IR Demo FEL was de-commissioned in late 2001 for an upgraded FEL for extending the IR power to over 10 kW and the ultraviolet power to over 1 kW. The FEL Upgrade achieved 10 kW of average power in the mid-IR (6 microns) in July of 2004, and its IR operation currently is being extended down to 1 micron. In addition, we have demonstrated the capability of on/off cycling and recovering over a megawatt of electron beam power without diminishing machine performance. A complementary UV FEL will come on-line within the next year. This paper presents a summary of the FEL characteristics, user community accomplishments with the IR Demo, and planned user experiments.

  1. High-energy detector

    DOEpatents

    Bolotnikov, Aleksey E.; Camarda, Giuseppe; Cui, Yonggang; James, Ralph B.

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  2. Energy Sources of T-Tauri Stars

    NASA Astrophysics Data System (ADS)

    Calvet, N.; Albarran, J.

    1984-06-01

    We empirically estimated the total energy loss from the atmospheric regions above the photo sphere in T Tauri stars. We have also estimated the flux input into the atmosphere by magnetohydrodynamic (MHD) aves produced in the subphotospheric convection zone. Within the uncertainties of both theory and observations, this flux seems to represent the basic energy input into the atmosphere provided that a large surface coverage of magnetic regions exists. In addition to this basic energy input from the convection zone the T Tauri atmospheres must have other energy sources, originating in the stellar surfitee. Among those we can include the flux of energy carried by Alfven waves resulting from the action of surface material motions on magnetic flux tubes, as well as dissipation and annihilation of magnetic fields in flare events. The observed decrease in emission line fluxes with luminosity seems to indicate that MHD wave fluxes heat the chromosphere, while the uppermost atmospheric regions require another source of heating.

  3. High energy gamma ray astronomy

    NASA Technical Reports Server (NTRS)

    Fichtel, Carl E.

    1987-01-01

    High energy gamma ray astronomy has evolved with the space age. Nonexistent twenty-five years ago, there is now a general sketch of the gamma ray sky which should develop into a detailed picture with the results expected to be forthcoming over the next decade. The galactic plane is the dominant feature of the gamma ray sky, the longitude and latitude distribution being generally correlated with galactic structural features including the spiral arms. Two molecular clouds were already seen. Two of the three strongest gamma ray sources are pulsars. The highly variable X-ray source Cygnus X-3 was seen at one time, but not another in the 100 MeV region, and it was also observed at very high energies. Beyond the Milky Way Galaxy, there is seen a diffuse radiation, whose origin remains uncertain, as well as at least one quasar, 3C 273. Looking to the future, the satellite opportunities for high energy gamma ray astronomy in the near term are the GAMMA-I planned to be launched in late 1987 and the Gamma Ray Observatory, scheduled for launch in 1990. The Gamma Ray Observatory will carry a total of four instruments covering the entire energy range from 30,000 eV to 3 x 10 to the 10th eV with over an order of magnitude increase in sensitivity relative to previous satellite instruments.

  4. High-power laser source evaluation

    SciTech Connect

    Back, C. A.; Decker, C. D.; Davis, J. F.; Dixit, S.; Grun, J.; Managan, R. A.; Serduke, F. J. D.; Simonson, G. F.; Suter, L. J.; Wuest, C. R.; Ze, F.

    1998-07-01

    Robust Nuclear-Weapons-Effects Testing (NWET) capability will be needed for the foreseeable future to ensure the performance and reliability, in nuclear environments, of the evolving U.S. stockpile of weapons and other assets. Ongoing research on the use of high-energy lasers to generate environments of utility in nuclear weapon radiation effects simulations is addressed in the work described in this report. Laser-driven hohlraums and a variety of other targets have been considered in an effort to develop NWET capability of the highest possible fidelity in above-ground experiments. The envelope of large-system test needs is shown as the gray region in fig. 1. It does not represent the spectrum of any device; it is just the envelope of the spectral region of outputs from a number of possible devices. It is a goal of our laser-only and ignition-capsule source development work to generate x rays that fall somewhere in this envelope. One of the earlier appearances of this envelope is in ref. 1. The Defense Special Weapons Agency provided important support for the work described herein. A total of $520K was provided in the 1997 IACROs 97-3022 for Source Development and 97-3048 for Facilitization. The period of performance specified in the Statement of Work ran from 28 February 1997 until 30 November 1997. This period was extended, by agreement with DSWA, for two reasons: 1) despite the stated period of performance, funds were not available at LLNL to begin this work until somewhat later in the fiscal year, and 2) we agreed to stretch the current resources until follow-on funds were in hand, to minimize effects of ramping down and up again. The tasks addressed in this report are the following: 1) Non-ignition-source model benchmarking and design. This involves analysis of existing and new data on laser-only sources to benchmark LASNEX predictions 2) Non-ignition-source development experiments 3) Ignition capsule design to improve total x-ray output and simplify target

  5. Controlling hazardous energy sources (lockout/tagout)

    NASA Technical Reports Server (NTRS)

    Dominguez, Manuel B.

    1991-01-01

    The minimum requirements as established by the Occupational Safety and Health Administration (OSHA) standard 29 CFR 1910.147 are discussed for preventing the unexpected operation of equipment or release of energy which could cause injury to personnel, damage to equipment, harm to the environment, or loss or compromise of test data. Safety requirements both for government and contractor personnel are explained for potentially hazardous energy sources during work operations at LeRC (Cleveland and Plum Brook Stations). Basic rules are presented to ensure protection against harmful exposures, and baseline implementation requirements are discussed from which detailed lockout/tagout procedures can be developed for individual equipment items. Examples of energy sources covered by this document include electrical, pneumatic, mechanical, chemical, cryogenic, thermal, spring tension/compression suspended or moving loads, and other potentially hazardous sources. Activities covered by this standard include, but are not limited to, construction, maintenance, installation, calibration, inspection, cleaning, or repair.

  6. An Inexpensive Source of High Voltage

    ERIC Educational Resources Information Center

    Saraiva, Carlos

    2012-01-01

    As a physics teacher I like recycling old apparatus and using them for demonstrations in my classes. In physics laboratories in schools, sources of high voltage include induction coils or electronic systems that can be bought from companies that sell lab equipment. But these sources can be very expensive. In this article, I will explain how you…

  7. High energy beam lines

    NASA Astrophysics Data System (ADS)

    Marchetto, M.; Laxdal, R. E.

    2014-01-01

    The ISAC post accelerator comprises an RFQ, DTL and SC-linac. The high energy beam lines connect the linear accelerators as well as deliver the accelerated beams to two different experimental areas. The medium energy beam transport (MEBT) line connects the RFQ to the DTL. The high energy beam transport (HEBT) line connects the DTL to the ISAC-I experimental stations (DRAGON, TUDA-I, GPS). The DTL to superconducting beam (DSB) transport line connects the ISAC-I and ISAC-II linacs. The superconducting energy beam transport (SEBT) line connects the SC linac to the ISAC-II experimental station (TUDA-II, HERACLES, TIGRESS, EMMA and GPS). All these lines have the function of transporting and matching the beams to the downstream sections by manipulating the transverse and longitudinal phase space. They also contain diagnostic devices to measure the beam properties.

  8. Methods of performing downhole operations using orbital vibrator energy sources

    DOEpatents

    Cole, Jack H.; Weinberg, David M.; Wilson, Dennis R.

    2004-02-17

    Methods of performing down hole operations in a wellbore. A vibrational source is positioned within a tubular member such that an annulus is formed between the vibrational source and an interior surface of the tubular member. A fluid medium, such as high bulk modulus drilling mud, is disposed within the annulus. The vibrational source forms a fluid coupling with the tubular member through the fluid medium to transfer vibrational energy to the tubular member. The vibrational energy may be used, for example, to free a stuck tubular, consolidate a cement slurry and/or detect voids within a cement slurry prior to the curing thereof.

  9. On the determination of the cosmic infrared background radiation from the high-energy spectrum of extragalactic gamma-ray sources

    NASA Technical Reports Server (NTRS)

    Dwek, Eli; Slavin, Jonathan

    1994-01-01

    In a recent paper Stecker, De Jager, & Salamon have suggested using the observed approximately MeV to TeV spectra of extragalactic gamma-ray sources as probes of the local density of the cosmic infrared background radiation (CIBR) and have subsequently claimed a first possible measurement of the CIBR from the analysis of the gamma-ray spectrum of Mrk 421 (De Jager, Stecker, & Salamon). The CIBR from normal galaxies consists of two components: a stellar emission component (CIBRs), and a thermal dust emission component (CIBRd). Photons with energies in the approximately 0.1-2 TeV range interact primarily with the CIBRs, whereas interactions with CIBRd dominate the absorption of photons in the approximately 2-100 TeV energy range. SDS 92 and DSS94 considered only the interaction of the gamma-rays with the dust emission component of the CIBR. We present here an improved analysis of the absorption of extragalactic TeV gamma rays by the CIBR, taking the dual nature of its origin into account. Applying the analysis to the observed gamma-ray spectrum of Mrk 421, a BL Lac object at z = 0.031, we find agreement with DSS94 tentative evidence for absorption by the CINRs. Our analysis therefore limits the detection of the CIBR to the approximately 15-40 micron wavelength regime which, considering the uncertainties in the highest energy (greater than 4 TeV) data and ion the possibility of absorption inside the source, many turn out to be an upper limit on its energy density. At shorter wavelengths (lambda approximately = 1-15 microns), where the gamma-ray interactions are dominated by the CIBRs, our analysis definitely yields only an upper limit on the energy density of the CIBR. In contrast, DSS94 have claimed a possible first measurement of the CIBR over the entire 1-120 micron wavelength region. The upper limit on the CIBRs and tentative detection of the CIBRd are consistent with normal galaxies contributing most of the energy to the CIBR, and constrain the contribution of

  10. Secondary School Teachers' Knowledge and Attitudes Towards Renewable Energy Sources

    NASA Astrophysics Data System (ADS)

    Liarakou, Georgia; Gavrilakis, Costas; Flouri, Eleni

    2009-04-01

    Investigating knowledge, perceptions as well as attitudes of public that concern various aspects of environmental issues is of high importance for Environmental Education. An integrated understanding of these parameters can properly support the planning of Environmental Education curriculum and relevant educational materials. In this survey we investigated knowledge and attitudes of secondary school teachers in Greece towards renewable energy sources, particularly wind and solar energy systems. A questionnaire with both open and close questions was used as the main methodological instrument. Findings revealed that although teachers were informed about renewable energy sources and well disposed towards these sources, they hardly expressed clear positions regarding several issues about wind and solar energy technologies and farms. Moreover such themes are limited integrated in teaching either as extra curricular educational programs or through the curriculum. These findings cannot confirm that teachers could influence students' opinion towards renewable energy systems. Thus, authorities should invest more in Environmental Education and relevant Teachers' Education.