Science.gov

Sample records for forbidden line intensities

  1. Effect of deuteron temperature on iron forbidden line intensities in rf-heated tokamak plasmas

    SciTech Connect

    Sato, K.; Suckewer, S.; Wouters, A.

    1987-05-01

    Two line ratios, the forbidden line at 845.5 A (2s/sup 2/2p /sup 2/P/sub 1/2/ - 2s/sup 2/2p /sup 2/P/sub 3/2/) to the allowed line at 135.7 A (2s/sup 2/2p /sup 2/P/sub 1/2/ - 2s2p/sup 2/ /sup 2/D/sub 3/2/) in Fe XXII and the forbidden line at 592.1 A (2s/sup 2/2p/sup 4/ /sup 3/P/sub 2/ - 2s/sup 2/2p/sup 4/ /sup 1/D/sub 2/) to the forbidden line at 1118.2 A (2s/sup 2/2p/sup 4/ /sup 3/P/sub 2/ - 2s/sup 2/2p/sup 4/ /sup 3/P/sub 1/) in Fe XIX, have been measured as the ion temperature-sensitive line ratios during rf heating in the Princeton Large Torus. The results indicate that deuteron collisions in plasmas of high deuteron temperature have a noticeable effect on the intensity of the forbidden lines. Measured relative intensities are compared with values from level population calculations, which include deuteron collisional excitation between the levels of the ground configuration. The agreement between the observed and calculated ratios is within 30%. A method for deuteron (or proton) temperature measurement in tokamak plasmas is discussed. 37 refs.

  2. Forbidden lines of np/q/ ions. I - Detailed balance and line intensity ratios

    NASA Technical Reports Server (NTRS)

    Kafatos, M.; Lynch, J. P.

    1980-01-01

    The detailed balance equations are solved in the ground state terms of 37 ions of C, N, O, Ne, Mg, Si, S and Fe; atomic data for 235 transitions of these ions are tabulated, and 14 line ratios of q = 2,4 ions and eight line ratios of q = 3 ions are graphed. Forbidden emission lines of these ions are in the far and near UV, visible, and near and far IR regions of the spectrum. In addition, detailed calculations of the relative populations of the levels of the ground state are presented as a function of temperature and density.

  3. Polarization of Coronal Forbidden Lines

    NASA Astrophysics Data System (ADS)

    Li, Hao; Landi Degl'Innocenti, Egidio; Qu, Zhongquan

    2017-03-01

    Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

  4. Polarization of Forbidden Coronal Emission Lines

    NASA Astrophysics Data System (ADS)

    Li, Hao

    2017-08-01

    Since the magnetic field is responsible for most manifestations of solar ac- tivity in the corona, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields. We present our investigation on polarization of forbidden coronal emission lines ( Fe XIV 5303 A, Fe X 6374 A Fe XI 7892 A, Fe XIII 10747 A, Si X 14300 A, Mg VIII 30280 A and Si IX 39290 A), which shows that Si IX 39290 A line may be a suitable line for future observation.

  5. Forbidden line emission from highly ionized atoms in tokamak plasmas

    NASA Technical Reports Server (NTRS)

    Feldman, U.; Doschek, G. A.; Bhatia, A. K.

    1982-01-01

    Considerable interest in the observation of forbidden spectral lines from highly ionized atoms in tokamak plasmas is related to the significance of such observations for plasma diagnostic applications. Atomic data for the elements Ti Cr, Mn, Fe, Ni, and Kr have been published by Feldman et al. (1980) and Bhatia et al. (1980). The present investigation is concerned with collisional excitation rate coefficients and radiative decay rates, which are interpolated for ions of elements between calcium, and krypton and for levels of the 2s2 2pk, 2s 2p(k+1), and 2p(k+2) configurations, and for the O I, N I, C I, B I, and Be I isoelectronic sequences. The provided interpolated atomic data can be employed to calculate level populations and relative line intensities for ions of the considered sequences, taking into account levels of the stated configurations. Important plasma diagnostic information provided by the forbidden lines includes the ion temperature

  6. Isophotes of a field in the Cygnus Loop photographed in the forbidden O III and forbidden N II + H-alpha lines

    NASA Astrophysics Data System (ADS)

    Sitnik, T. G.; Toropova, M. S.

    1982-12-01

    From interference-filter image-tube photographs of a 9 arc min field in the western part of the Cygnus Loop supernova remnant, taken in the 5007 forbidden O III and 6584, 6563 forbidden N II + H-alpha lines, sets of isophotes are derived by an equidensitometry technique based on the Sabattier effect. The emission regions in these lines exhibit a relatively displacement, interpreted as evidence for radiative cooling of the gas behind the shock generated in the supernova outburst. An explanation is offered for the differing morphology of the nebular filaments in the forbiddden O III and forbidden N II + H-alpha lines. The anomalously high I (O III)/I(H-beta) intensity ratio may reflect a spatial separation of the corresponding emission zones.

  7. The optical depth of the 158 micron forbidden C-12 II line - Detection of the F = 1 - 0 forbidden C-13 II hyperfine-structure component. [in Orion nebula

    NASA Technical Reports Server (NTRS)

    Stacey, G. J.; Townes, C. H.; Geis, N.; Madden, S. C.; Herrmann, F.; Genzel, R.; Poglitsch, A.; Jackson, J. M.

    1991-01-01

    The detection of the F = 1 - 0 hyperfine component of the 158-micron forbidden C-13 II fine-structure line in the interstellar medium is reported. A 12-point intensity map was obtained of the forbidden C-13 distribution over the inner 190-arcsec (R.A.) X 190-arcsec (decl.) regions of the Orion Nebula using an imaging Fabry-Perot interferometer. The forbidden C-12 II/C-13 II line intensity ratio varies significantly over the region mapped. It is highest (86 +/-0) in the core of the Orion H II region, and significantly lower (62 +/-7) in the outer regions of the map, reflecting higher optical depth in the forbidden C-12 II line here. It is suggested that this enhanced optical depth is the result of limb brightening of the optically thin forbidden C-13 II line at the edges of the bowl-shaped H II region blister.

  8. The optical depth of the 158 micron forbidden C-12 II line - Detection of the F = 1 - 0 forbidden C-13 II hyperfine-structure component. [in Orion nebula

    NASA Technical Reports Server (NTRS)

    Stacey, G. J.; Townes, C. H.; Geis, N.; Madden, S. C.; Herrmann, F.; Genzel, R.; Poglitsch, A.; Jackson, J. M.

    1991-01-01

    The detection of the F = 1 - 0 hyperfine component of the 158-micron forbidden C-13 II fine-structure line in the interstellar medium is reported. A 12-point intensity map was obtained of the forbidden C-13 distribution over the inner 190-arcsec (R.A.) X 190-arcsec (decl.) regions of the Orion Nebula using an imaging Fabry-Perot interferometer. The forbidden C-12 II/C-13 II line intensity ratio varies significantly over the region mapped. It is highest (86 +/-0) in the core of the Orion H II region, and significantly lower (62 +/-7) in the outer regions of the map, reflecting higher optical depth in the forbidden C-12 II line here. It is suggested that this enhanced optical depth is the result of limb brightening of the optically thin forbidden C-13 II line at the edges of the bowl-shaped H II region blister.

  9. The calculation of vibrational intensities in forbidden electronic transitions

    NASA Astrophysics Data System (ADS)

    Johnson, Philip M.; Xu, Haifeng; Sears, Trevor J.

    2006-10-01

    A method is described for the use of electronic structure and Franck-Condon factor programs in the calculation of the vibrational intensities in forbidden electronic transitions. Using the B˜B22-X˜B12 electronic transition of benzonitrile cation as a test case, transition moments were calculated using the symmetry adapted cluster/configuration interaction method at various points along the normal mode displacements of the molecule, from which transition moment derivatives were obtained. The transition moments were found to vary almost linearly with respect to the normal mode displacements. Using these, along with Franck-Condon factors, an expansion of the transition moment with respect to the normal coordinates provides a measure of vibrational intensities, including the effects of geometry change and Duschinsky rotation [Acta Physicochim. URSS 7, 551 (1937)]. Second order terms in the moment expansion are calculated, and it is determined that they must be included if the intensity of combination bands is to be properly obtained.

  10. The calculation of vibrational intensities in forbidden electronic transitions.

    PubMed

    Johnson, Philip M; Xu, Haifeng; Sears, Trevor J

    2006-10-28

    A method is described for the use of electronic structure and Franck-Condon factor programs in the calculation of the vibrational intensities in forbidden electronic transitions. Using the B 2B2-X 2B1 electronic transition of benzonitrile cation as a test case, transition moments were calculated using the symmetry adapted cluster/configuration interaction method at various points along the normal mode displacements of the molecule, from which transition moment derivatives were obtained. The transition moments were found to vary almost linearly with respect to the normal mode displacements. Using these, along with Franck-Condon factors, an expansion of the transition moment with respect to the normal coordinates provides a measure of vibrational intensities, including the effects of geometry change and Duschinsky rotation [Acta Physicochim. URSS 7, 551 (1937)]. Second order terms in the moment expansion are calculated, and it is determined that they must be included if the intensity of combination bands is to be properly obtained.

  11. Radio emission and the forbidden line region of Seyfert galaxies

    SciTech Connect

    Ulvestad, J.S.

    1981-01-01

    The results of an extensive program of mapping Seyfert galaxies using the Very Large Array radio telescope are presented. Unlike the majority of radio galaxies, the radio emission in most Seyferts is confined to the inner few kiloparsecs (or less) of the galaxy. This scale is similar to the size of the region in which optical forbidden line emission occurs. Six double (or triple) radio sources have been mapped now in Seyfert galaxies. Approximately ten more galaxies shown more diffuse emission or are resolved only slightly. In almost all galaxies, the central radio peak, when present, coincides with the optical continuum peak. In every double or triple radio source, the outer radio lobes straddle that optical peak. The major axes of the double and triple radio sources may be correlated with the directions of greatest elongation of the optical line-emitting cloud complexes. However, the radio source axes do not appear to be related to the major or minor axes of the outer optical continuum isophotes of the Seyfert galaxies. Synchrotron emission is the dominant source of radio photons in all the galaxies observed. Thermal processes contribute, on the average, no more than about 6% of the total radio emission at 4.885 GHz. Using standard assumptions, radio luminosities, magnetic fields, and total energy contents have been calculated for the observed galaxies. The triple radio source in NGC 5548 has been studied in detail. The properties of NGC 5548 have been used to investigate some theoretical aspects of the double and triple sources and their relationship to the forbidden line region (FLR).

  12. Magellanic cloud planetary nebula with suspected strong forbidden iron lines

    PubMed Central

    Aller, L. H.; Czyzak, S. J.

    1983-01-01

    The relatively high-excitation nebula (Westerlund-Smith object 25) in the large Magellanic cloud shows prominent forbidden lines of [Ar IV], the close [Ne IV] pair λ4724, 4726, [Ca V] λ5309, [Fe V] λ4227, and probably [Fe VI] and [Fe VII], as well. A conventional interpretation of observations secured with a vidicon detector at the Cerro Tololo 4-m telescopes indicates an essentially “normal” helium abundance but depletions of N, O, Ne, and other elements with respect to our own galaxy. When a comparison is made with diffuse nebulae or H II regions in the large Magellanic cloud, we find helium to be more abundant, oxygen to be depleted, and nitrogen, neon, and argon to be comparable. The abundance of sulfur is uncertain. Iron in the gaseous phase is certainly more plentiful than in conventional planetaries. PMID:16593294

  13. Detection of Forbidden Line Components of Lithium-like Carbon in Stellar Spectra

    NASA Astrophysics Data System (ADS)

    Werner, Klaus; Rauch, Thomas; Hoyer, Denny; Quinet, Pascal

    2016-08-01

    We report the first identification of forbidden line components from an element heavier than helium in the spectrum of astrophysical plasmas. So far, these components were identified only in laboratory plasmas and not in astrophysical objects. Forbidden components are well known for neutral helium lines in hot stars, particularly in helium-rich post-AGB stars and white dwarfs. We discovered that two hitherto unidentified lines in the ultraviolet spectra of hot hydrogen-deficient (pre-) white dwarfs can be identified as forbidden line components of triply ionized carbon (C iv). The forbidden components (3p-4f and 3d-4d) appear in the blue and red wings of the strong, Stark broadened 3p-4d and 3d-4f lines at 1108 Å and 1169 Å, respectively. They are visible over a wide effective temperature range (60,000-200,000 K) in helium-rich (DO) white dwarfs and PG 1159 stars that have strongly oversolar carbon abundances.

  14. The interacting winds of Eta Carinae: Observed forbidden line changes and the Forbidden Blue(-Shifted) Crab

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Madura, Thomas; Corcoran, Michael F.; Teodoro, Mairan; Richardson, Noel; Hamaguchi, Kenji; Groh, Jose H.; Hillier, Desmond John; Damineli, Augusto; Weigelt, Gerd

    2015-01-01

    The massive binary, Eta Carinae (EC), produces such massive winds that strong forbidden line emission of singly- and doubly-ionized iron traces wind-wind interactions from the current cycle plus fossil interactions from one, two and three 5.54-year cycles ago.With an eccentricity of >0.9, the >90 solar mass primary (EC-A) and >30 solar mass secondary (EC-B) approach to within 1.5 AU during periastron and recede to nearly 30 AU across apastron. The wind-wind structures move outward driven by the 420 km/s primary wind interacting with the ~3000 km/s secondary wind yielding partially-accelerated compressed primary wind shells that are excited by mid-UV from EC-A and in limited lines of sight, FUV from EC-B.These structures are spectroscopically and spatially resolved by HST's Space Telescope Imaging Spectrograph. At critical binary phases, we have mapped the central 2'x2' region in the light of [Fe III] and [Fe II] with spatial resolution of 0.12' and velocity resolution of 40 km/s.1) The bulk of forbidden emission originates from the large cavity northwest of EC and is due to ionization of massive ejecta from the 1840s and 1890s eruptions. The brightest clumps are the Weigelt Blobs C and D, but there are additionally multiple, fainter emission clumps. Weigelt B appears to have faded.2) Three concentric, red-shifted [FeII] arcs expand at ~470 km/s excited by mid-UV of EC-A.3) The structure of primarily blue-shifted [Fe III] emission resembles a Maryland Blue Crab. The claws appear at the early stages of the high-excitation recovery from the periastron passage, expand at radial velocities exceeding the primary wind terminal velocity, 420 km/s and fade as the binary system approaches periastron with the primary wind enveloping the FUV radiation from EC-B.4) All [Fe III] emission faded by late June 2014 and disappeared by August 2, 2014, the beginning of periastron passage.Comparisons to HST/STIS observations between 1998 to 2004.3 indicate long-term fading of [Fe II

  15. Detection of forbidden line O I 63 micron emission from the galactic center

    NASA Technical Reports Server (NTRS)

    Lester, D. F.; Werner, M. W.; Storey, J. W. V.; Watson, D. M.; Townes, C. H.

    1981-01-01

    The detection of the 63 micron line of forbidden line O I is reported for three positions in the H II region complex Sgr A at the galactic center. Velocity resolution of the line indicates that the emitting material has both rotational and radial motion of magnitude similar to that of the ionized gas in the core, and that a substantial amount of the emitting material lies within the central few parsecs of the Galaxy. A model in which forbidden line O I is collisionally excited by neutral hydrogen, either from the warm region ahead of an ionization front or behind a shock, is proposed and gives a total mass of hot, neutral gas within the central 3 pc of the Galaxy of between 10 and 1000 solar mass. A limit on the flux of this line has been set for Sgr B2.

  16. Mapping low- and high-density clouds in astrophysical nebulae by imaging forbidden line emission

    NASA Astrophysics Data System (ADS)

    Steiner, J. E.; Menezes, R. B.; Ricci, T. V.; Oliveira, A. S.

    2009-06-01

    Emission line ratios have been essential for determining physical parameters such as gas temperature and density in astrophysical gaseous nebulae. With the advent of panoramic spectroscopic devices, images of regions with emission lines related to these physical parameters can, in principle, also be produced. We show that, with observations from modern instruments, it is possible to transform images taken from density-sensitive forbidden lines into images of emission from high- and low-density clouds by applying a transformation matrix. In order to achieve this, images of the pairs of density-sensitive lines as well as the adjacent continuum have to be observed and combined. We have computed the critical densities for a series of pairs of lines in the infrared, optical, ultraviolet and X-rays bands, and calculated the pair line intensity ratios in the high- and low-density limit using a four- and five-level atom approximation. In order to illustrate the method, we applied it to Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (GMOS-IFU) data of two galactic nuclei. We conclude that this method provides new information of astrophysical interest, especially for mapping low- and high-density clouds; for this reason, we call it `the ld/hd imaging method'. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the National Science Foundation (United States); the Science and Technology Facilities Council (United Kingdom); the National Research Council (Canada), CONICYT (Chile); the Australian Research Council (Australia); Ministério da Ciência e Tecnologia (Brazil) and Secretaria de Ciencia y Tecnologia (Argentina). E-mail: steiner@astro.iag.usp.br

  17. From Forbidden Coronal Lines to Meaningful Coronal Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Judge, P. G.; Habbal, S.; Landi, E.

    2013-12-01

    We review methods to measure magnetic fields within the corona using the polarized light in magnetic-dipole (M1) lines. We are particularly interested in both the global magnetic-field evolution over a solar cycle, and the local storage of magnetic free energy within coronal plasmas. We address commonly held skepticisms concerning angular ambiguities and line-of-sight confusion. We argue that ambiguities are, in principle, no worse than more familiar remotely sensed photospheric vector fields, and that the diagnosis of M1 line data would benefit from simultaneous observations of EUV lines. Based on calculations and data from eclipses, we discuss the most promising lines and different approaches that might be used. We point to the S-like [Fe xi] line ( J=2 to J=1) at 789.2 nm as a prime target line (for the Advanced Technology Solar Telescope (ATST) for example) to augment the hotter 1074.7 and 1079.8 nm Si-like lines of [Fe xiii] currently observed by the Coronal Multi-channel Polarimeter (CoMP). Significant breakthroughs will be made possible with the new generation of coronagraphs, in three distinct ways: i) through single-point inversions (which encompasses also the analysis of MHD wave modes), ii) using direct comparisons of synthetic MHD or force-free models with polarization data, and iii) using tomographic techniques.

  18. Spectroscopic Diagnostics of Solar Magnetic Flux Ropes Using Iron Forbidden Line

    NASA Astrophysics Data System (ADS)

    Cheng, X.; Ding, M. D.

    2016-05-01

    In this Letter, we present Interface Region Imaging Spectrograph Fe xxi 1354.08 Å forbidden line emission of two magnetic flux ropes (MFRs) that caused two fast coronal mass ejections with velocities of ≥1000 km s-1 and strong flares (X1.6 and M6.5) on 2014 September 10 and 2015 June 22, respectively. The extreme-ultraviolet images at the 131 and 94 Å passbands provided by the Atmospheric Imaging Assembly on board Solar Dynamics Observatory reveal that both MFRs initially appear as suspended hot channel-like structures. Interestingly, part of the MFRs is also visible in the Fe xxi 1354.08 forbidden line, even prior to the eruption, e.g., for the SOL2014-09-10 event. However, the line emission is very weak and that only appears at a few locations but not the whole structure of the MFRs. This implies that the MFRs could be comprised of different threads with different temperatures and densities, based on the fact that the formation of the Fe xxi forbidden line requires a critical temperature (˜11.5 MK) and density. Moreover, the line shows a non-thermal broadening and a blueshift in the early phase. It suggests that magnetic reconnection at that time has initiated; it not only heats the MFR and, at the same time, produces a non-thermal broadening of the Fe xxi line but also produces the poloidal flux, leading to the ascension of the MFRs.

  19. Seyfert galaxy narrow-line regions. I - Observations of forbidden O III lambda 5007

    NASA Technical Reports Server (NTRS)

    Vrtilek, J. M.; Carleton, N. P.

    1985-01-01

    High-resolution (23 km/s) spectra of the forbidden O III emission line at 500.7 nm from the nuclear regions of 32 Seyfert galaxies and low-redshift QSOs have been obtained at the Smithsonian Institution/University of Arizona Multiple Mirror Telescope. The properties of the data are summarized by a group of measures which efficiently describe the entire line profiles, are stable in the presence of noise, and have easily visualized geometric meaning. The distributions of line profile measures are shown. In particular, typical forbidden O III FWHM values of 200-520 km/s (mean + or - 1 sigma) and a highly significant tendency for the lines to fall off more slowly on the blue than on the red side of the peak have been found, in agreement with previous work. Using galaxian system velocities obtained from absorption-line measurements, the distribution of differences between forbidden O III emission-line velocities and galaxian system velocities has been determined; in disagreement with previous work, this distribution has been found to be consistent with symmetry about zero difference velocity.

  20. 2D forbidden oxygen line emission maps for various comets

    NASA Astrophysics Data System (ADS)

    Cessateur, Gaël; De Keyser, Johan; Maggiolo, Romain; Rubin, Martin; Gronoff, Guillaume; Gibbons, Andrew; Jehin, Emmanuel; Dhooghe, Frédéric; Gunell, Herbert; Vaeck, Nathalie; Loreau, Jérôme

    2017-04-01

    We present here a photochemical model for oxygen line emissions for various comets at 577.7 nm (green line), 630 nm, and 636.4 nm (red-doublet). The in-situ detection of molecular oxygen by Rosetta (67P/Churyumov-Gerasimenko) and Giotto (1P/Halley) makes an update of the usual photochemical model of oxygen line emissions necessary. As the water production rate is increasing, a 2D approach becomes more suitable rather than the usual 1D approach. Indeed, for very active comets such as 1P/Halley or C/1995 O1 Hale-Bopp, neutral densities are high enough to fully absorb the solar UV flux. The resulting 2D emission maps then do not have a spherical symmetry, and become thus interesting tools to be compared with in-situ and/or ground based observations. One major problem relative to the photochemical models lies in the cross section uncertainties. Based on a Monte-Carlo approach, we have assessed the impact of the uncertainties of the dissociation cross section of the neutral species on the resulting oxygen lines emissions.

  1. Trace Metals in PG1159 Stars and the First Identification of Metal Line Forbidden Components in Astrophysical Sources

    NASA Astrophysics Data System (ADS)

    Werner, K.; Hoyer, D.; Rauch, T.; Kruk, J. W.; Quinet, P.

    2017-03-01

    We report on results of our spectroscopic analysis of five PG1159 stars. The measured abundances of trace elements are in agreement with the intershell composition of Asymptotic Giant Branch stellar models. We also report on our discovery of forbidden components of C IV lines. This is the first detection of forbidden components from elements heavier than helium in astrophysical sources.

  2. On the use of forbidden lines as density diagnostics in stratified media

    NASA Technical Reports Server (NTRS)

    Safier, Pedro N.

    1992-01-01

    The influence of density and ionization gradients on the observed density-sensitive forbidden-line ratios from a spatially unresolved source is investigated by means of a simple model. In order to assess the role played by the source geometry, both spherical and cylindrical systems where all spatial dependences are given by power laws are considered. It is shown that the present ratios can be used to estimate the spatial dependence of density and ionization as well as the source geometry.

  3. ACCURATE RITZ WAVELENGTHS OF PARITY-FORBIDDEN [Co II] AND [V II] LINES OF ASTROPHYSICAL INTEREST

    SciTech Connect

    Ruffoni, M. P.; Pickering, J. C.

    2013-08-15

    We report a comprehensive list of accurate Ritz wavelengths for parity-forbidden [Co II] and [V II] lines obtained from the analysis of energy levels measured in the laboratory with Fourier transform emission spectroscopy. Such lines, particularly those in the infrared, are in demand for the analysis of low-density astrophysical plasmas in and around objects such as planetary nebulae, star-forming regions, and active galactic nuclei. Transitions between all known metastable levels of Co II and V II are included in our analysis, producing wavelengths for 1477 [V II] lines and 782 [Co II] lines. Of these, 170 [V II] lines and 171 [Co II] lines arise from transitions with calculated transition probabilities greater than 1 Multiplication-Sign 10{sup -2} s{sup -1} and upper level excitations of less than 5 eV, and thus are likely to be observed in astrophysical spectra.

  4. Improved low-lying energy levels determined from solar coronal forbidden and spin-forbidden lines in the 500-1500 A range

    SciTech Connect

    Feldman, U.; Doschek, G.A. . E-mail: george.doschek@nrl.navy.mil

    2007-09-15

    We list observed parity-forbidden and spin-forbidden lines in the 500-1600 A range emitted by solar coronal plasmas and derive improved energy levels from their wavelengths. The lines, emitted by astrophysical abundant elements, belong to transitions within the ground configurations of the type ns{sup 2} np {sup k}, for n = 2, 3 and k = 0-5, and between the lowest term of the first excited configuration 2s2p {sup k+1} and the 2s{sup 2}2p {sup k} ground configurations for k = 0, 1, 2. For each line we give the newly measured wavelength, and the measured or predicted wavelength from the NIST Atomic Spectra Database (ASD) (which except for a few cases includes the previously reported compilation of Kaufman and Sugar [J. Phys. Chem. Ref. Data 15 (1986) 321]), and the values of the transition probability taken from the ASD and CHIANTI database. The list contains measured wavelengths of 136 lines of which over 100 were not available for the Kaufman and Sugar compilation. In addition we provide energy levels that were derived from the reported lines.

  5. FORBIDDEN AND INTERCOMBINATION LINES OF RR TELESCOPII: WAVELENGTH MEASUREMENTS AND ENERGY LEVELS

    SciTech Connect

    Young, P. R.; Feldman, U.; Lobel, A.

    2011-10-01

    Ultraviolet and visible spectra of the symbiotic nova RR Telescopii are used to derive reference wavelengths for many forbidden and intercombination transitions of ions +1 to +6 of elements C, N, O, Ne, Na, Mg, Al, Si, P, S, Cl, Ar, K, and Ca. The wavelengths are then used to determine new energy values for the levels within the ions' ground configurations or first excited configuration. The spectra were recorded by the Space Telescope Imaging Spectrograph of the Hubble Space Telescope and the Ultraviolet Echelle Spectrograph of the European Southern Observatory in 2000 and 1999, respectively, and cover 1140-6915 A. Particular care was taken to assess the accuracy of the wavelength scale between the two instruments. An investigation of the profiles of the emission lines reveals that the nebula consists of at least two plasma components at different velocities. The components have different densities, and a simple model of the lines' emissions demonstrates that most of the lines principally arise from the high density component. Only these lines were used for the wavelength study.

  6. First Detection of Sign-reversed Linear Polarization from the Forbidden [O I] 630.03 nm Line

    NASA Astrophysics Data System (ADS)

    de Wijn, A. G.; Socas-Navarro, H.; Vitas, N.

    2017-02-01

    We report on the detection of linear polarization of the forbidden [O i] 630.03 nm spectral line. The observations were carried out in the broader context of the determination of the solar oxygen abundance, an important problem in astrophysics that still remains unresolved. We obtained spectro-polarimetric data of the forbidden [O i] line at 630.03 nm as well as other neighboring permitted lines with the Solar Optical Telescope of the Hinode satellite. A novel averaging technique was used, yielding very high signal-to-noise ratios in excess of 105. We confirm that the linear polarization is sign-reversed compared to permitted lines as a result of the line being dominated by a magnetic dipole transition. Our observations open a new window for solar oxygen abundance studies, offering an alternative method to disentangle the Ni i blend from the [O i] line at 630.03 nm that has the advantage of simple LTE formation physics.

  7. VizieR Online Data Catalog: Parity-forbidden [Co II] and [V II] lines (Ruffoni+, 2013)

    NASA Astrophysics Data System (ADS)

    Ruffoni, M. P.; Pickering, J. C.

    2013-09-01

    The Ritz wavelengths of the parity-forbidden [Co II] and [V II] lines reported here were calculated, respectively, from the accurate Co II energy levels reported by Pickering et al. (1998ApJS..117..261P) and the revised accurate V II energy levels measured by Thorne et al. (2013, Cat. J/ApJS/207/13). (4 data files).

  8. Separation between Allowed and Forbidden Component of the He I 447 nm Line in High Electron Density Plasma

    SciTech Connect

    Ivkovic, M.; Jovicevic, S.; Konjevic, N.; Gonzalez, M. A.; Gigosos, M. A.

    2008-10-22

    Stark broadened He I 447.1 nm line is measured and the dependence of the separation between its allowed and forbidden components upon electron density is analyzed. Experimental results are compared with computer simulation results and with former experimental results.

  9. Transition Probabilities for the 1815 and 3344 Å Forbidden Lines of NE III

    NASA Astrophysics Data System (ADS)

    Daw, Adrian; Parkinson, William H.; Smith, Peter L.; Calamai, Anthony G.

    2000-04-01

    We have measured the radiative lifetime of the 2s22p4 1S0 metastable level of Ne2+ (Ne III) to be 223+/-11 ms at the 90% confidence level by observing the photons emitted at 1815 Å by a decaying population of 1S0 Ne2+ ions produced and stored in a radio-frequency ion trap. This is the first lifetime measurement for an excited term of a ground configuration ion in the second row of the periodic table. The transition probabilities (A-values) for the forbidden transitions in the ground configurations of these ions are required for astrophysical line-ratio diagnostics. Using calculated branching ratios, we estimate that A(λ1815)=1.94+/-0.17 and A(λ3344)=2.55+/-0.19 s-1. Because these numbers have a sum with an experimentally determined uncertainty of 5%, they will provide more accurate results than the calculated A-values for determining electron temperature and density from astrophysical Ne III line ratios.

  10. Transition Probabilities for the 1815 and 3344 Å Forbidden Lines of Ne iii.

    PubMed

    Daw; Parkinson; Smith; Calamai

    2000-04-20

    We have measured the radiative lifetime of the 2s22p4 1S0 metastable level of Ne2+ (Ne iii) to be 223+/-11 ms at the 90% confidence level by observing the photons emitted at 1815 Å by a decaying population of 1S0 Ne2+ ions produced and stored in a radio-frequency ion trap. This is the first lifetime measurement for an excited term of a ground configuration ion in the second row of the periodic table. The transition probabilities (A-values) for the forbidden transitions in the ground configurations of these ions are required for astrophysical line-ratio diagnostics. Using calculated branching ratios, we estimate that A&parl0;lambda1815&parr0;=1.94+/-0.17 and A&parl0;lambda3344&parr0;=2.55+/-0.19 s-1. Because these numbers have a sum with an experimentally determined uncertainty of 5%, they will provide more accurate results than the calculated A-values for determining electron temperature and density from astrophysical Ne iii line ratios.

  11. 3D Modeling of Forbidden Line Emission in the Binary Wind Interaction Region of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Madura, Thomas; Gull, T. R.; Owocki, S.; Okazaki, A. T.; Russell, C. M. P.

    2010-01-01

    We present recent work using three-dimensional (3D) Smoothed Particle Hydrodynamics (SPH) simulations to model the high ([Fe III], [Ar III], [Ne III] and [S III]) and low ([Fe II], [Ni II]) ionization forbidden emission lines observed in Eta Carinae using the HST/STIS. These structures are interpreted as the time-averaged, outer extensions of the primary wind and the wind-wind interaction region directly excited by the FUV of the hot companion star of this massive binary system. We discuss how analyzing the results of the 3D SPH simulations and synthetic slit spectra and comparing them to the spectra obtained with the HST/STIS helps us determine the absolute orientation of the binary orbit and helps remove the degeneracy inherent to models based solely on the observed RXTE X-ray light curve. A key point of this work is that spatially resolved observations like those with HST/STIS and comparison to 3D models are necessary to determine the alignment or misalignment of the orbital angular momentum axis with the Homunculus, or correspondingly, the alignment of the orbital plane with the Homunculus skirt.

  12. Abundances of argon, sulfur, and neon in six galactic H II regions from infrared forbidden lines

    NASA Technical Reports Server (NTRS)

    Herter, T.; Helfer, H. L.; Forrest, W. J.; Mccarthy, J.; Houck, J. R.; Willner, S. P.; Puetter, R. C.; Rudy, R. J.; Soifer, B. T.; Pipher, J. L.

    1981-01-01

    Airborne measurements of the Ar II (6.99 micron) and S III (18.71 micron) forbidden lines for six compact H II regions are presented, as well as ground-based 2-4 micron and 8-13 micron spectroscopy if not already published. From these data and radio data, lower limits to the elemental abundances of Ar, Ne, and S are deduced. G29.9-0.0, at 5 kpc from the galactic center, is overabundant in all these elements. The other five regions (at distances 6-13 kpc from the center) mainly appear to be consistent with standard abundances, with the exception of G75.84 + 0.4 at 10 kpc from the galactic center, which is overabundant in S. However, preliminary results on G12.8-0.2 at 6 kpc from the galactic center suggest a possible underabundance. A large statistical sample of H II regions is required in order to determine if there is a radial gradient in the heavy element abundances of the Galaxy.

  13. 3D Modeling of Forbidden Line Emission in the Binary Wind Interaction Region of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Madura, Thomas; Gull, T. R.; Owocki, S.; Okazaki, A. T.; Russell, C. M. P.

    2010-01-01

    We present recent work using three-dimensional (3D) Smoothed Particle Hydrodynamics (SPH) simulations to model the high ([Fe III], [Ar III], [Ne III] and [S III]) and low ([Fe II], [Ni II]) ionization forbidden emission lines observed in Eta Carinae using the HST/STIS. These structures are interpreted as the time-averaged, outer extensions of the primary wind and the wind-wind interaction region directly excited by the FUV of the hot companion star of this massive binary system. We discuss how analyzing the results of the 3D SPH simulations and synthetic slit spectra and comparing them to the spectra obtained with the HST/STIS helps us determine the absolute orientation of the binary orbit and helps remove the degeneracy inherent to models based solely on the observed RXTE X-ray light curve. A key point of this work is that spatially resolved observations like those with HST/STIS and comparison to 3D models are necessary to determine the alignment or misalignment of the orbital angular momentum axis with the Homunculus, or correspondingly, the alignment of the orbital plane with the Homunculus skirt.

  14. Forbidden line and H-alpha profiles in T Tauri star spectra - A probe of anisotropic mass outflows and circumstellar disks

    NASA Technical Reports Server (NTRS)

    Edwards, Suzan; Heyer, Ingeborg; Cabrit, Sylvie; Strom, Stephen E.; Strom, Karen M.

    1987-01-01

    The results of a high-resolution spectroscopic study of 10 T Tauri stars (TTS) and two Herbig emission stars are presented based on red echelle spectra including the lines of forbidden O I 6300 A, forbidden N II 6584 A, forbidden S II 6716, 6731 A, as well as H-alpha. The forbidden lines display a continuous progression of profile types. The velocity structure in the forbidden lines is critically examined and compared to computed line profiles for a number of different wind models. Constant velocity spherical or conical winds fail to reproduce the observed line profiles, which are better explained by a wind with a latitude-dependent velocity field. A prediction of the wind model correlating the velocity of the reversal at H-alpha and the forbidden line velocity structure as a function of the view angle to the star is explored. Estimates of the average densities and sizes for the TTS forbidden emission regions are presented, and mass-loss rates are computed. IRAS far-IR fluxes are used to estimate the disk sizes.

  15. Tracing Slow Winds from T Tauri Stars via Low Velocity Forbidden Line Emission

    NASA Astrophysics Data System (ADS)

    Simon, Molly; Pascucci, Ilaria; Edwards, Suzan; Feng, Wanda; Rigliaco, Elisabetta; Gorti, Uma; Hollenbach, David J.; Tuttle Keane, James

    2016-06-01

    Protoplanetary disks are a natural result of star formation, and they provide the material from which planets form. The evolutional and eventual dispersal of protoplanetary disks play critical roles in determining the final architecture of planetary systems. Models of protoplanetary disk evolution suggest that viscous accretion of disk gas onto the central star and photoevaporation driven by high-energy photons from the central star are the main mechanisms that drive disk dispersal. Understanding when photoevaporation begins to dominate over viscous accretion is critically important for models of planet formation and planetary migration. Using Keck/HIRES (resolution of ~ 7 km/s) we analyze three low excitation forbidden lines ([O I] 6300 Å, [O I] 5577 Å, and [S II] 6731 Å) previously determined to trace winds (including photoevaporative winds). These winds can be separated into two components, a high velocity component (HVC) with blueshifts between ~30 - 150 km/s, and a low velocity component (LVC) with blueshifts on the order of ~5 km/s (Hartigan et al. 1995). We selected a sample of 32 pre-main sequence T Tauri stars in the Taurus-Auriga star-forming region (plus TW Hya) with disks that span a range of evolutionary stages. We focus on the origin of the LVC specifically, which we are able to separate into a broad component (BC) and a narrow component (NC) due to the high resolution of our optical spectra. We focus our analysis on the [O I] 6300 Å emission feature, which is detected in 30/33 of our targets. Interestingly, we find wind diagnostics consistent with photoevaporation for only 21% of our sample. We can, however, conclude that a specific component of the LVC is tracing a magnetohydrodynamic (MHD) wind rather than a photoevaporative wind. We will present the details behind these findings and the implications they have for planet formation more generally.

  16. Forbidden atomic transitions driven by an intensity-modulated laser trap.

    PubMed

    Moore, Kaitlin R; Anderson, Sarah E; Raithel, Georg

    2015-01-20

    Spectroscopy is an essential tool in understanding and manipulating quantum systems, such as atoms and molecules. The model describing spectroscopy includes the multipole-field interaction, which leads to established spectroscopic selection rules, and an interaction that is quadratic in the field, which is not often employed. However, spectroscopy using the quadratic (ponderomotive) interaction promises two significant advantages over spectroscopy using the multipole-field interaction: flexible transition rules and vastly improved spatial addressability of the quantum system. Here we demonstrate ponderomotive spectroscopy by using optical-lattice-trapped Rydberg atoms, pulsating the lattice light and driving a microwave atomic transition that would otherwise be forbidden by established spectroscopic selection rules. This ability to measure frequencies of previously inaccessible transitions makes possible improved determinations of atomic characteristics and constants underlying physics. The spatial resolution of ponderomotive spectroscopy is orders of magnitude better than the transition frequency would suggest, promising single-site addressability in dense particle arrays for quantum computing applications.

  17. Infrared spectrum involving forbidden transitions & coriolis interaction and identification of optically pumped far infrared laser lines in asymmetrically mono-deuterated methanol (Methanol-D1)

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Indra

    2016-05-01

    In this paper new type of ΔK = 2 and 0 transitions have been identified in the Fourier Transform spectrum of Methanol-D1 (CH2DOH). These transitions are normally forbidden but a "Coriolis" type interaction with nearby states is believed to be contributing sufficient transition strength through intensity borrowing effect. This is the first time such forbidden transitions are reported to be identified in the excited states, in this molecule. The present conjecture is supported by observation of a many strong allowed transitions to upper terminating levels which are seen to be highly perturbed. This conclusion has been reached by comparing calculated energy levels using known molecular parameters (Pearson et al., 2012; Coudert et al., 2014; El Hilali et al., 2011; Quade et al., 1998; Richard Quade, 1998, 1999; Mukhopadhyay, 1997) and the actually observed FIR lines. The upper levels are seen to be upshifted from expected position. A closer look at the calculated energy values seems to indicate a possible interaction between the above states and other proximate torsional-rotational states could occur. The possible candidates for the interacting level manifolds are narrowed down through the presence of the forbidden transition. We also take the opportunity to propose alternate rotational quantum numbers for some of the assignments recently reported in the literature (El Hilali et al., 2011). Some ambiguities are pointed out on the data and the reported analysis. There remain too many such irregularities and we propose to gather a large body assigned transitions in a future catalog. Assignments and relevant comments on optically pumped FIR laser radiation are also made.

  18. Forbidden Line Emission in the Eccentric Spectroscopic Binaries DQ Tauri and UZ Tauri E Monitored over an Orbital Period

    NASA Astrophysics Data System (ADS)

    Huerta, M.; Hartigan, P.; White, R. J.

    2005-02-01

    We present echelle spectroscopy of the close pre-main-sequence binary star systems DQ Tau and UZ Tau E. Over a 16 day time interval we acquired 14 nights of spectra for DQ Tau and 12 nights of spectra for UZ Tau E. This represents the entire phase of DQ Tau and 63% of the phase of UZ Tau E. As expected, photospheric lines such as Li I λ6707 clearly split into two components while the primary and secondary orbit one another, as did the permitted line He I λ5876. Unlike the photospheric features, the forbidden lines of [O I] λ6300 and [O I] λ5577 retain the same shape throughout the orbit. Therefore, these lines must originate outside the immediate vicinity of the two stars and any circumstellar disks that participate in the orbital motion of the stars.

  19. The Fe XIV spectrum: Predicted line intensities and solar identifications

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.; Keenan, F. P.; Conlon, E. S.; Widing, K. G.

    1994-01-01

    Level populations and line intensities have been calculated in a 40-level model of Fe XIV which includes the configuations 3p(exp 3) and 3s3p3d. The results have been compared against intensities of weaker, unidentified, or tentatively classified lines in published solar line lists including a recent Goddard Space Flight Center/Solar Extreme Ultraviolet Telescope and Spectrograph (GSFC/SERTS) high-resolution list, and in presently measured archival Naval Research Laboratory (NRL)/S082A active region spectra. Seven new lines are identified as Fe XIV transitions; five other observed, unidentified lines are considered to be Fe XIV transitions on the basis of wavelength coincidence, but require further observations to obtain photometric intensities for verification; one line at 216.93 A is shown to be due to some other ion than Fe XIV. In addition, a unique forbidden infrared (approx. equal to 1.25 micrometer(s)) line originating in the high metastable level 3s3p3d(F(sub 9/2)-4) is found to have an unusual intensity dependence on electron density.

  20. Photochemistry of forbidden oxygen lines in the inner coma of 67P/Churyumov-Gerasimenko.

    PubMed

    Cessateur, G; Keyser, J De; Maggiolo, R; Gibbons, A; Gronoff, G; Gunell, H; Dhooghe, F; Loreau, J; Vaeck, N; Altwegg, K; Bieler, A; Briois, C; Calmonte, U; Combi, M R; Fiethe, B; Fuselier, S A; Gombosi, T I; Hässig, M; Le Roy, L; Neefs, E; Rubin, M; Sémon, T

    2016-01-01

    Observations of the green and red-doublet emission lines have previously been realized for several comets. We present here a chemistry-emission coupled model to study the production and loss mechanisms of the O((1)S) and O((1)D) states, which are responsible for the emission lines of interest for comet 67P/Churyumov-Gerasimenko. The recent discovery of O2 in significant abundance relative to water 3.80 ± 0.85% within the coma of 67P has been taken into consideration for the first time in such models. We evaluate the effect of the presence of O2 on the green to red-doublet emission intensity ratio, which is traditionally used to assess the CO2 abundance within cometary atmospheres. Model simulations, solving the continuity equation with transport, show that not taking O2 into account leads to an underestimation of the CO2 abundance within 67P, with a relative error of about 25%. This strongly suggests that the green to red-doublet emission intensity ratio alone is not a proper tool for determining the CO2 abundance, as previously suggested. Indeed, there is no compelling reason why O2 would not be a common cometary volatile, making revision of earlier assessments regarding the CO2 abundance in cometary atmospheres necessary. The large uncertainties of the CO2 photodissociation cross section imply that more studies are required in order to better constrain the O((1)S) and O((1)D) production through this mechanism. Space weather phenomena, such as powerful solar flares, could be used as tools for doing so, providing additional information on a good estimation of the O2 abundance within cometary atmospheres.

  1. Towards Perfect Water Line Intensities

    NASA Astrophysics Data System (ADS)

    Lodi, L.; Tennyson, J.

    2012-06-01

    Over the last ten years the increased availability of computational resources and the steady refinement of theoretical methods have permitted more and more accurate first principle calculations of water-vapor spectra as exemplified, e.g., by the very successful BT2 line list both line positions and intensities, a reliable dipole moment surface (DMS), affecting line intensities. It is also very useful to several application to give reasonable uncertainty bars for computed quantities, an aspect which traditionally has received little attention. We report here recent progress leading to very accurate room-temperature linelists covering the range 0.05-20 000 cm-1, complete with uncertainty bars, for the H_218O and H_217O water isotopologues Line intensities were produced using a recent DMS produced by our group which is capable of giving line intensites accurate to 1% for most medium and strong transitions. Line positions are based if possible on the experimentally derived energy levels recently produced by a IUPAC task group and have a typical accuracy of 0.0002 cm-1; when experimentally derived energy levels are unavailable calculated line position are provided, with an accuracy of the order of 0.2 cm-1. An extension to the main isotopologue H_216O is currently underway. R. J. Barber, J. Tennyson, G. J. Harris and R. N. Tolchenov, Mon. Not. R. Astron. Soc. {368}, 1087-1094 (2006). L. Lodi and J. Tennyson, J. Quant. Spectrosc. Radiat. Trans. (2012), doi:10.1016/j.jqsrt.2012.02.023 L. Lodi, J. Tennyson and O. L. Polyansky, J. Chem. Phys. {135}, 034113 (2011). J. Tennyson at al., J. Quant. Spectrosc. Radiat. Trans. {110}, 573-96 (2009).

  2. The photospheric solar oxygen project. II. Non-concordance of the oxygen abundance derived from two forbidden lines

    NASA Astrophysics Data System (ADS)

    Caffau, E.; Ludwig, H.-G.; Malherbe, J.-M.; Bonifacio, P.; Steffen, M.; Monaco, L.

    2013-06-01

    Context. In the Sun, the two forbidden [O i] lines at 630 and 636 nm were previously found to provide discrepant oxygen abundances. Aims: We investigate whether this discrepancy is peculiar to the Sun or whether it is also observed in other stars. Methods: We make use of high-resolution, high signal-to-noise ratio spectra of four dwarf to turn-off stars, five giant stars, and one sub-giant star observed with THEMIS, HARPS, and UVES to investigate the coherence of the two lines. Results: The two lines provide oxygen abundances that are consistent, within observational errors, in all the giant stars examined by us. On the other hand, for the two dwarf stars for which a measurement was possible, for Procyon, and for the sub-giant star Capella, the 636 nm line provides systematically higher oxygen abundances, as already seen for the Sun. Conclusions: The only two possible reasons for the discrepancy are a serious error in the oscillator strength of the Ni i line blending the 630 nm line or the presence of an unknown blend in the 636 nm line, which makes the feature stronger. The CN lines blending the 636 nm line cannot be responsible for the discrepancy. The Ca i autoionisation line, on the red wing of which the 636 nm line is formed, is not well modelled by our synthetic spectra. However, a better reproduction of this line would result in even higher abundances from the 636 nm, thus increasing the discrepancy. Based on observations collected at ESO Paranal Observatory, Programme 182.D-5053(A).

  3. The intensity of forbidden torsional transitions in electronic spectra of molecules with a 6-fold barrier: Application to toluenes

    SciTech Connect

    Virgo, Edwina A.; Gascooke, Jason R.; Lawrance, Warren D.

    2014-04-21

    Franck-Condon forbidden transitions involving methyl rotor modes are seen in the S{sub 1} ← S{sub 0} spectrum of toluene and toluene-like molecules. The strongest of these rotor transitions (m{sup ″} = 1 → m{sup ′} = 2, m{sup ″} = 0 → m{sup ′} = 3a{sub 1}{sup ″}, and m{sup ″} = 1 → m{sup ′} = 4) have been shown by Walker et al. [J. Chem. Phys. 102, 8718 (1995)] to gain intensity through the rotor equivalent of the Herzberg-Teller mechanism. Despite the m{sup ″} = 0 → m{sup ′} = 3a{sub 2}{sup ″} transition being forbidden in this formalism, it is sporadically observed. We show that this transition derives oscillator strength from incomplete mixing of the −3 and +3 free rotor basis states due to torsion-rotation coupling. Calculations demonstrate that this mechanism quantitatively explains the intensities observed for toluene, including their temperature dependence. Because the −3/+3 mixing is weakest when the torsional barrier height, V{sub 6}, is small, the m{sup ″} = 0 → m{sup ′} = 3a{sub 2}{sup ″} transition increases in intensity as |V{sub 6}| decreases. The temperature and |V{sub 6}| dependencies explain why reports of the 0 → 3a{sub 2}{sup ″} transition have been intermittent. The torsion-rotation coupling mechanism is predicted to also give significant intensity to m = 0 → m = 6a{sub 2}{sup ′} transitions relative to m = 0 → m = 6a{sub 1}{sup ′} transitions and to provide intensity to 0 → 3a{sub 2} transitions in molecules with a 3-fold (V{sub 3}) barrier. Comparison between the observed and calculated rotor band contours shows, unexpectedly, that the 3a{sub 1}{sup ″} constants fail to predict the 3a{sub 2}{sup ″} contour despite these two states being derived from the same free rotor basis states. Comparison with the observed spectrum also reveals differences in the separation of the S{sub 1} 3a{sub 2}{sup ″} and 3a{sub 1}{sup ″} levels. The V{sub 6} value

  4. The excitation mechanism of Fe XIV 5303 A forbidden line in the inner regions of solar corona

    NASA Astrophysics Data System (ADS)

    Raju, K. P.; Desai, J. N.; Chandrasekhar, T.; Ashok, N. M.

    1991-12-01

    The line intensity of the green coronal line and the continuum intensity are derived from the filter and white light photographs of the solar corona obtained during the 1980 total solar eclipse. Ratio of the line to continuum intensity is plotted against the radial distance r(= R/R0, R0 is the solar radius), in various position angles. A simple model assuming an electron density dependence of the line and continuum intensities suggests a dominant collisional mechanism for the excitation of the line in the innermost regions (about 1.4 R0). The measured line to continuum ratio tends to a constant value at different radial distances in different position angles. The constancy of the measured line to continuum ratio indicates significant radiative excitation beyond 1.4 R0, in some of the position angles.

  5. Space Telescope Imaging Spectrograph Survey of Far-Ultraviolet Coronal Forbidden Lines in Late-Type Stars

    NASA Astrophysics Data System (ADS)

    Ayres, Thomas R.; Brown, Alexander; Harper, Graham M.; Osten, Rachel A.; Linsky, Jeffrey L.; Wood, Brian E.; Redfield, Seth

    2003-02-01

    We describe an extensive search with the Space Telescope Imaging Spectrograph (STIS) for ultraviolet coronal (T>106 K) forbidden lines in a sample of 29 F-M dwarfs, giants, and supergiants. Measuring coronal lines in the 1150-1700 Å band with STIS has important advantages of superior velocity resolution and an absolute wavelength calibration compared with using the Chandra or XMM-Newton grating spectrometers to observe permitted transitions of the same ion stages in the kilovolt X-ray region. Fe XII λλ1242, 1349 (T~2×106 K) and Fe XXI λ1354 (107 K) are well known from solar studies and have been reported in previous stellar work. A search for other coronal forbidden lines in the 1200-1600 Å region was largely negative. The few candidate identifications (e.g., Ar XIII λ1330 and Ca XV λ1375) are too faint to be diagnostically useful. We add new dwarfs to the list of Fe XII detections, including the nearby solar twin α Cen A (G2 V). Clear detections of Fe XXI were obtained in dMe stars, active giants, a short-period RS CVn binary, and possibly in active solar-type dwarfs. We developed a semiempirical method for removing the C I blend that partially affects the Fe XXI λ1354 profile. As discussed recently by Johnson et al., Capella (α Aur; G8 III+G1 III) displays clear Fe XXI variability between Goddard High-Resolution Spectograph (GHRS) and STIS observations 4 yr apart, which is apparently due to a substantial decline in the contribution from the G8 primary. We present an alternative model of the GHRS and STIS era profiles using information in the two sets of line shapes jointly, as well as knowledge of the behavior of Fe XXI profiles of other late-G ``clump'' giants similar to Capella G8. The full survey sample also provides a context for the apparent variability: the Fe XXI flux of the G8 star in the GHRS spectrum is nearly identical (in LFeXXI/Lbol) to other clump giants of similar LX/Lbol, but it had dropped at least a factor of 6 in the STIS measurement

  6. Optical diagnostics for the highly populated tail of an electron energy distribution function in very-high-frequency capacitively coupled plasma using spin- and dipole-forbidden lines

    NASA Astrophysics Data System (ADS)

    Roh, Hyun-Joon; Kim, Nam-Kyun; Ryu, Sangwon; Jang, Yunchang; Kim, Gon-Ho

    2017-06-01

    A novel method is proposed to determine an electron energy distribution function (EEDF) that includes the highly populated tail originated by energetic beam-like electrons (>20 eV), which often occur in narrow gap, very-high-frequency capacitively coupled plasma (VHF-CCP). This method combines conventional Langmuir probe analysis to represent the EEDF in the low-energy regime and the line-ratio method taken from the optical emission spectrum to represent the highly populated tail of the EEDF. Here the emission lines are chosen with consideration of the excitation rates, which are a function of the shape of the cross-section of the spin- and dipole-forbidden states of an argon atom and the EEDF at corresponding energy. In this method, the analytical EEDF model is chosen for the composition of the Maxwellian for low-energy (bulk) electrons, and Schulze’s time-averaged form of the shifted Maxwellian (Schulze et al 2008 J. Phys. D: Appl. Phys. 41 042003) is chosen for the highly populated tail of the EEDF. The variables of the time-averaged form of the shifted Maxwellian, the fraction and mean energy of the beam-like electrons, are determined using an emission model of line-intensity ratios, which describes the line-intensities as a function of the EEDF. This method is advantageous for the diagnostics of a time-averaged EEDF with a highly populated tail, especially where this is due to beam-like electrons that originate from stochastic heating, compared to a two-temperature EEDF.

  7. Spatially distinct Raman scattering characteristics of individual ZnO nanorods under controlled polarization: intense end scattering from forbidden modes.

    PubMed

    Hansen, Matthew; Truong, Johnson; Xie, Tian; Hahm, Jong-In

    2017-06-22

    In this study, we characterize incident/scattered polarization-specific and NR position-resolved Raman scattering behaviors of individual zinc oxide nanorods (ZnO NRs). We quantify Raman signals from the five key ZnO phonon modes of E2L, E2H-2L, A1T, E1T, and E2H, and reveal the NR position-dependent Raman scattering characteristics of the phonon modes per given light-matter interaction geometry. We then present Raman intensity maps and elucidate Raman behaviors consistent and incongruous with Raman selection rules. In particular, we identify an intriguing Raman scattering phenomenon from the forbidden modes, distinctively occurring at the two NR ends. Their unexpectedly strong and localized scattering signals at the NR termini are contrasted by the scattering behaviors from the rest of the NR positions agreeing with the selection predictions. By carrying out control measurements on isotropic ZnO microparticles (MPs), we ascertain that the unique NR position-specific Raman responses observed on ZnO NRs originate from their high shape anisotropy. Owing to the superior optical property coupled with reduced dimensionality and high geometric anisotropy, ZnO NRs have gained much attention recently for use in optoelectronic, photonic, and biosensor technologies. Raman scattering has been increasingly exploited as a noninvasive and sensitive analytical tool to investigate NR properties pertinent to these applications. Hence, our endeavors, explicitly providing the spatially distinct, polarized Raman scattering behaviors from individual ZnO NRs, will be central to the correct interpretation of Raman data of both the individual and ensemble NRs as well as to the accurate correlation of the measurement outcomes to their chemical/physical/optical properties. Our efforts may also promote novel applications for polarized Raman scattering whose optical outputs on the various positions along the ZnO NRs can be selectively modulated.

  8. Catalog of the H-alpha + N II forbidden-line emission features in the Kepler SNR

    SciTech Connect

    Dodorico, S.; Bandiera, R.; Danziger, J.; Focardi, P.

    1986-06-01

    A deep image of the Kepler SNR has been obtained in the light of H-alpha + N II forbidden-line with the faint object spectrograph and camera (EFOSC) and a CCD detector at the ESO 3.6 m telescope. The visibility of the optically emitting knots of ionized gas has been greatly enhanced by subtraction of the continuum radiation. Features as faint as 2 percent of the night-sky brightness have been identified and a half-shell of emission is clearly revealed. The total H-alpha luminosity of the ionized gas is estimated to be 8.3 x 10 to the 45th photons/s at a distance of 5 kpc implying a mass of ionized hydrogen of about 0.02 solar mass. An automatic searching program has been used to identify and list individual emission features in the continuum-subtracted image. A catalog with accurate celestial positions and approximate fluxes for 64 emission-line knots is given. 13 references.

  9. The N(^2D - ^4S) 520 nm forbidden doublet transition in the nightglow: An experimental test of the theoretical intensity ratio

    NASA Astrophysics Data System (ADS)

    Slanger, T. G.; Cosby, P. C.; Huestis, D. L.

    2003-04-01

    N(^2D) is an important species in the nighttime ionosphere, as its reaction with O_2 is a principal source of NO. Its modeled concentration peaks near 200 km, at approximately 4 × 10^5 cm-3. Nightglow emission in the optically forbidden lines at 519.8 and 520.0 nm is quite weak, a consequence of the combination of an extremely long radiative lifetime, about 10^5 sec, and quenching by O-atoms, O_2, and N_2. The radiative lifetime is known only from theory, and various calculations lead to a range of possible values for the intensity ratio R = I(519.8)/I(520.0) of 1.5-2.5. On the observational side, Hernandez and Turtle [1969] determined a range of R = 1.3-1.9 in the nightglow, and Sivjee et al. [1981] reported a variable ratio in aurorae, between 1.2 and 1.6. From sky spectra obtained at the Keck II telescope on Mauna Kea, we have accumulated eighty-five 30-60 minute data sets, from March and October, 2000, and April, 2001, over 13 nights of astronomical observations. We find R to have a quite precise value of 1.760± 0.012 (2-σ). There is no difference between the three data sets in terms of the extracted ratio, which therefore seems to be independent of external conditions. At the same time, determination of the O(^1D - ^3P) doublet intensity ratio, I(630.0)/I(636.4), gives a value of 3.03 ± 0.01, the statistical expectation. G. Hernandez and J. P. Turtle, Planet. Space Sci. 17, 675, 1969. G. G. Sivjee, C. S. Deehr, and K. Henricksen, J. Geophys. Res. 86, 1581, 1981.

  10. Forbidden coronal iron line emission in the Puppis A shock front: The effect of inhomogeneities

    NASA Technical Reports Server (NTRS)

    Teske, Richard G.; Petre, Robert

    1986-01-01

    We have obtained CCD images of the shock front at the eastern rim of Puppis A in (Fe X) lambda 6374 and (Fe XIV) lambda 5303 and have compared the optical data to Einstein HRI soft X-ray data. The observed part of the remnant is complex, containing density irregularities. Optical and X-ray data are consistent in showing a nearly flat gradient of ionization behind the shock. To determine conditions in the shock, scans of surface brightness across it in the optical lines were compared to surface brightnesses predicted by idealized Sedov models. We were unable to match both the red and green line scans by a simple, single-component model, and have ascribed the failure to the presence of the density inhomogeneities. Our result has important implications for the determination of SNR shock front models by means of fitting X-ray data with Sedov models.

  11. 2D-photochemical model for forbidden oxygen line emission for comets

    NASA Astrophysics Data System (ADS)

    Cessateur, G.; De Keyser, J.; Maggiolo, R.; Rubin, M.; Gronoff, G.; Gibbons, A.; Jehin, E.; Dhooghe, F.; Gunell, H.; Vaeck, N.; Loreau, J.

    2016-12-01

    Emissions at 577.7 nm (green line), 630 nm, and 636.4 nm (red-doublet) come from the deactivation of the O(1S) and O(1D) oxygen states. The photodissociation of H2O, CO and CO2 in the inner coma are responsible for the production of those oxygen states. This list of species had to be extended to include molecular oxygen since its in-situ detection by the Rosetta and Giotto missions. This contribution will present a 2D-photochemical model that calculates the number densities of the O(1S) and O(1D) oxygen states in the comae of various comets, taking the production, the loss and the transport mechanisms into account. For very active comets, e.g. 1P/Halley, a 1D model does not suffice since the solar UV flux is strongly absorbed resulting in an overestimation of the red-doublet and green lines emissions by a factor of 2. Even when assuming spherical symmetry of the neutral gas coma, the phase angle of the observation introduces asymmetries in the measured emission line ratios. Emission maps are deduced from our 2D-model, which can directly be compared to ground and/or in-situ observations.

  12. 2D photochemical model for forbidden oxygen line emission for comet 1P/Halley

    NASA Astrophysics Data System (ADS)

    Cessateur, G.; De Keyser, J.; Maggiolo, R.; Rubin, M.; Gronoff, G.; Gibbons, A.; Jehin, E.; Dhooghe, F.; Gunell, H.; Vaeck, N.; Loreau, J.

    2016-11-01

    We present here a 2D model of photochemistry for computing the production and loss mechanisms of the O(1S) and O(1D) states, which are responsible for the emission lines at 577.7, 630, and 636.4 nm, in case of the comet 1P/Halley. The presence of O2 within cometary atmospheres, measured by the in situ Rosetta and Giotto missions, necessitates a revision of the usual photochemical models. Indeed, the photodissociation of molecular oxygen also leads to a significant production of oxygen in excited electronic states. In order to correctly model the solar ultraviolet (UV) flux absorption, we consider here a 2D configuration. While the green to red-doublet ratio is not affected by the solar UV flux absorption, estimates of the red-doublet and green lines emissions are, however, overestimated by a factor of 2 in the 1D model compared to the 2D model. Considering a spherical symmetry, emission maps can be deduced from the 2D model in order to be directly compared to ground and/or in situ observations.

  13. Observations of the 63 micron forbidden OI emission line in the Orion and Omega Nebulae

    NASA Technical Reports Server (NTRS)

    Melnick, G.; Gull, G. E.; Harwit, M.

    1979-01-01

    Observations of 63-micron neutral oxygen emission from the Orion and Omega Nebulae are reported which were carried out from the NASA Lear Jet flying at an altitude of approximately 13.7 km. The best estimate for the 3 P 1 - 3 P 2 transition wavelength is shown to be 63.2 microns, and the detected fluxes are found to be extraordinarily high (amounting to approximately 600 suns in M42 at 0.5 kpc and to about 2900 suns in the line in M17 at 2 kpc). Attempts are made to estimate the minimum temperature and other parameters of the emitting region in Orion. It is concluded that conditions not too different from those permitted by some current models appear to provide fluxes that agree in order of magnitude with those observed.

  14. Transition moments, Franck-Condon factors, and lifetimes of forbidden transitions - Calculation of the intensity of the Cameron system of CO.

    NASA Technical Reports Server (NTRS)

    James, T. C.

    1971-01-01

    Discussion of the factors affecting the intensity of forbidden transitions in diatomic molecules. It is shown that using Franck-Condon factors to predict relative band intensities is less reliable for forbidden transitions than it is for allowed transitions. The intensity of the 0,0 and 1,0 bands of the a super 3 pi-super 1 sigma Cameron system of CO are calculated using perturbation theory. The intensity arises from spin-orbit mixing of the A super 1 pi state with the a super 3 pi state. From the known spin-orbit coupling constant of the a super 1 pi state and the known intensity of the fourth positive A super 1 pi-super 1 sigma transition, the oscillator strengths of the 0,0 and 1,0 bands are calculated to be 1.63 x 10 to the minus 7th power and 1.99 x 10 to the minus 7th power. Lifetimes of various rotational levels are shown to range from 2.9 to several hundred milliseconds.-

  15. Transition moments, Franck-Condon factors, and lifetimes of forbidden transitions - Calculation of the intensity of the Cameron system of CO.

    NASA Technical Reports Server (NTRS)

    James, T. C.

    1971-01-01

    Discussion of the factors affecting the intensity of forbidden transitions in diatomic molecules. It is shown that using Franck-Condon factors to predict relative band intensities is less reliable for forbidden transitions than it is for allowed transitions. The intensity of the 0,0 and 1,0 bands of the a super 3 pi-super 1 sigma Cameron system of CO are calculated using perturbation theory. The intensity arises from spin-orbit mixing of the A super 1 pi state with the a super 3 pi state. From the known spin-orbit coupling constant of the a super 1 pi state and the known intensity of the fourth positive A super 1 pi-super 1 sigma transition, the oscillator strengths of the 0,0 and 1,0 bands are calculated to be 1.63 x 10 to the minus 7th power and 1.99 x 10 to the minus 7th power. Lifetimes of various rotational levels are shown to range from 2.9 to several hundred milliseconds.-

  16. The neutral oxygen spectrum. 1: Collisionally excited level populations and line intensities under optically thin conditions

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1995-01-01

    This is the first paper in a projected program to produce quantitative information on the spectrum of the neutral oxygen atom under a variety of excitation conditions. Radiative rates and effective collision strengths are assembled from the recent literature where available, or are calculated for as yet untreated transitions using the University College superstructure/distorted-wave computer package, to produce a complete set of atomic data for a 13 hybrid level model of neutral oxygen. Level populations and relative intensities for 28 allowed, inter-combination, and forbidden oxygen lines are computed, under optically thin conditions, for the electron density range 4.0 less than log N(sub e) less than 12.0 and the electron temperature values T(sub e) = 5000, 10,000, 20,000, 50,000, and 100,000 K. Preliminary applications to observed intercombination/allowed and forbidden/allowed line ratios are discussed.

  17. The neutral oxygen spectrum. 1: Collisionally excited level populations and line intensities under optically thin conditions

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1995-01-01

    This is the first paper in a projected program to produce quantitative information on the spectrum of the neutral oxygen atom under a variety of excitation conditions. Radiative rates and effective collision strengths are assembled from the recent literature where available, or are calculated for as yet untreated transitions using the University College superstructure/distorted-wave computer package, to produce a complete set of atomic data for a 13 hybrid level model of neutral oxygen. Level populations and relative intensities for 28 allowed, inter-combination, and forbidden oxygen lines are computed, under optically thin conditions, for the electron density range 4.0 less than log N(sub e) less than 12.0 and the electron temperature values T(sub e) = 5000, 10,000, 20,000, 50,000, and 100,000 K. Preliminary applications to observed intercombination/allowed and forbidden/allowed line ratios are discussed.

  18. Atomic Data and Spectral Line Intensities for Ar XII

    NASA Technical Reports Server (NTRS)

    Eissner, W.; Landi, E.; Bhatia, A. K.

    2004-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ar XII. The configurations used are 2s(sup 2)p(sup 3), 2s(sup 2)p(sup 4), 2p(sup 5), 2s(sup 2)2p(sup 2)3s, 2s(sup 2)2p(sup 2)3p, and 2s(sup 2)2p(sup 2)3d giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies: 35, 70, 105, 140 and 175 Ry. They are complemented by Coulomb-Born limits towards infinite collision energy for forbidden transitions and line strengths for optically allowed transitions. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8)-10(exp 14)/cm(exp 3) at an electron temperature of log T(sub e)/K = 6.4, corresponding to maximum abundance of AR-XII. Relative spectral line intensities are calculated.

  19. Atomic Data and Spectral Line Intensities for Ar XII

    NASA Technical Reports Server (NTRS)

    Eissner, W.; Landi, E.; Bhatia, A. K.

    2004-01-01

    Electron impact collision strengths; energy levels; oscillator strengths and spontaneous radiative decay rates are calculated for Ar XII. The configurations used are 2s(exp 2)2p(exp 3), 2s2p(exp4), 2p(exp 5), 2s22p23s, 2s(exp 2)2p(exp 2)3p, and 2s(exp 2)2p(exp 2)3d giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies: 35,70, 105, 140 and 175 Ry. They are complemented by Coulomb-Born limits towards infinite collision energy for forbidden transitions and line strengths for optically allowed transitions. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8)-101(exp 14) cm(exp -3) at an electron temperature of log T(sub e)/K = 6.4, corresponding to maximum abundance of Ar XII. Relative spectral line intensities are calculated.

  20. Atomic Data and Spectral Line Intensities for Ar XII

    NASA Technical Reports Server (NTRS)

    Eissner, W.; Landi, E.; Bhatia, A. K.

    2004-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ar XII. The configurations used are 2s(sup 2)p(sup 3), 2s(sup 2)p(sup 4), 2p(sup 5), 2s(sup 2)2p(sup 2)3s, 2s(sup 2)2p(sup 2)3p, and 2s(sup 2)2p(sup 2)3d giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies: 35, 70, 105, 140 and 175 Ry. They are complemented by Coulomb-Born limits towards infinite collision energy for forbidden transitions and line strengths for optically allowed transitions. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8)-10(exp 14)/cm(exp 3) at an electron temperature of log T(sub e)/K = 6.4, corresponding to maximum abundance of AR-XII. Relative spectral line intensities are calculated.

  1. Atomic data and spectral line intensities for Ar XII

    NASA Astrophysics Data System (ADS)

    Eissner, W.; Landi, E.; Bhatia, A. K.

    2005-03-01

    Electron impact collision strengths are computed for Ar XII in a distorted wave approach and energy levels, oscillator strengths, spontaneous radiative decay rates for the collision target, as well as collisional high energy limits are obtained from an atomic structure calculation. The target expansion comprises the six spectroscopic configurations 2s 22p 3, 2s2p 4, 2p 5, 2s 22p 23s, 2s 22p 23p, and 2s 22p 23d, giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies: 35, 70, 105, 140, and 175 Ry. They are complemented by Coulomb-Born limits towards infinite collision energy for forbidden transitions and line strengths for optically allowed transitions. Excitation rate coefficients are obtained as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10 8-10 14 cm -3 at an electron temperature of log Te/K = 6.4, corresponding to maximum abundance of Ar XII. Relative spectral line intensities are also calculated.

  2. Optical line intensities in the Trifid nebula

    SciTech Connect

    Lynds, B.T.; Oneil, E.J. Jr.

    1985-07-01

    Observations of the Trifid nebula (M20) obtained in H-alpha; He I (587.6 nm); and the forbidden lines of N II (658.3 nm), S II (671.6 and 673 nm), O III (500.7 nm), and O II (272.6 and 372.9 nm) using either the CIT long-slit spectrograph or a direct-mode CCD with narrow-band interference filters on the 92-cm telescope at KPNO are reported. The data are presented in extensive graphs and characterized in detail and a model is proposed to explain the scattering measurements. Findings discussed include a single central O7 V star with Teff = about 37,500 K, a dusty plasma ionized by this star, mean nebular electron density 150/cu cm, a central hole of radius 0.2 times that of the ionized zone, dust extending beyond the ionized region, overall temperature 7000-8000 K, filament temperatures up to 9000 K, dust optical depth 1.5 at H-beta, dust albedo 0.5, emission-nebula radius 2.8 pc, and total mass about 1700 solar mass (comprising 340 solar mass ionized material, about 800 solar mass unionized cloud material, and about 600 solar mass in an outer dust sphere). 18 references.

  3. Computer program for determining rotational line intensity factors for diatomic molecules

    NASA Technical Reports Server (NTRS)

    Whiting, E. E.

    1973-01-01

    A FORTRAN IV computer program, that provides a new research tool for determining reliable rotational line intensity factors (also known as Honl-London factors), for most electric and magnetic dipole allowed diatomic transitions, is described in detail. This users manual includes instructions for preparing the input data, a program listing, detailed flow charts, and three sample cases. The program is applicable to spin-allowed dipole transitions with either or both states intermediate between Hund's case (a) and Hund's case (b) coupling and to spin-forbidden dipole transitions with either or both states intermediate between Hund's case (c) and Hund's case (b) coupling.

  4. Line Positions, Intensities And Line Shape Parameters Of PH3 Near 4.4 µm

    NASA Astrophysics Data System (ADS)

    Venkataraman, Malathy; Benner, D. C.; Kleiner, I.; Brown, L. R.; Sams, R. L.; Fletcher, L. N.

    2012-10-01

    Accurate knowledge of spectral line parameters in the 2000 to 2400 cm-1 region of PH3 is important for the CASSINI/VIMS exploration of dynamics and chemistry of Saturn and for the correct interpretation of future Jovian observations by JUNO and ESA’s newly-selected mission JUICE. Since the available intensity information for phosphine is inconsistent, we measured line positions and intensities for over 4000 individual transitions in the 2ν2, ν2+ν4, 2ν4, ν1 and the ν3 bands from analyzing high-resolution, high S/N spectra recorded at room temperature using two Fourier transform spectrometers (FTS); the Bruker IFS 125 HR FTS at PNNL and the Kitt Peak FTS at the National Solar Observatory in Arizona. In addition to line positions and intensities, self-broadened half width and self-induced pressure-shift coefficients were also measured for about 800 transitions for the various bands. The strong Coriolis and other types of interactions occurring among the various vibrational levels result in a large number of forbidden transitions as well as cause A+A- splittings in transitions with K″ that are multiples of 3. Line mixing was detected between several A+A- pairs of transitions; and self- line mixing coefficients were measured for several such pairs of transitions by applying the off-diagonal relaxation matrix formalism of Levy et al.1 A multispectrum nonlinear least squares technique2 employing a non-Voigt line shape including line mixing and speed dependence was used in fitting all the spectra simultaneously. Present results are compared with other reported values. This research is supported by NASA’s Outer Planets Research Program. References [1] A. Lévy et al., In “Spectroscopy of the Earth’s Atmosphere and Interstellar Medium”, Ed. K, Narahari Rao and A. Weber, Boston, Academic Press; p, 261-337 (1992). [2] D. C. Benner et al., J Quant. Spectrosc. Radiat. Transfer 53, 705, 1995.

  5. A survey of the 158 micron forbidden C II fine-structure line in the central 50 parsecs of the Galaxy

    NASA Technical Reports Server (NTRS)

    Poglitsch, A.; Geis, N.; Haggerty, M.; Jackson, J.; Stacey, G. J.

    1991-01-01

    NASA's Kuiper Airborne Observatory has been used to conduct an extensive, velocity-resolved survey at 1-arcsec resolution of the 158-micron forbidden C II fine-structure line emission in the central 50 pc of the Galaxy. The emission is found to be strongest toward the rotating circumnuclear disk surrounding Sgr A West; a continuous bridge of the emission connects the Sgr A complex to the thermal radio filaments in the radio arc 10 arcmin north of the center. This suggests a direct physical connection. The brightest emission occurs preferentially near the edges of the massive Galactic center molecular clouds. It is concluded that these clouds are predominantly ionized by external UV photons.

  6. A survey of the 158 micron forbidden C II fine-structure line in the central 50 parsecs of the Galaxy

    NASA Technical Reports Server (NTRS)

    Poglitsch, A.; Geis, N.; Haggerty, M.; Jackson, J.; Stacey, G. J.

    1991-01-01

    NASA's Kuiper Airborne Observatory has been used to conduct an extensive, velocity-resolved survey at 1-arcsec resolution of the 158-micron forbidden C II fine-structure line emission in the central 50 pc of the Galaxy. The emission is found to be strongest toward the rotating circumnuclear disk surrounding Sgr A West; a continuous bridge of the emission connects the Sgr A complex to the thermal radio filaments in the radio arc 10 arcmin north of the center. This suggests a direct physical connection. The brightest emission occurs preferentially near the edges of the massive Galactic center molecular clouds. It is concluded that these clouds are predominantly ionized by external UV photons.

  7. Methane Line Intensities: Near and Far IR

    NASA Astrophysics Data System (ADS)

    Brown, Linda R.; Devi, V. Malathy; Wishnow, Edward H.; Sung, Keeyoon; Crawford, Timothy J.; Mantz, Arlan W.; Smith, Mary Ann H.; Predoi-Cross, Adriana; Benner, D. Chris

    2014-11-01

    Accurate knowledge of line intensities is crucial input for radiance calculations to interpret atmospheric observations of planets and moons. We have therefore undertaken extensive laboratory studies to measure the methane spectrum line-by-line in order to improve theoretical quantum mechanical modeling for molecular spectroscopy databases (e. g. HITRAN and GEISA) used by planetary astronomers. Preliminary results will be presented for selected ro-vibrational transitions in both the near-IR (1.66 and 2.2 - 2.4 microns) and the far-IR (80 - 120 microns) regions. For this, we have recorded high-resolution spectra (instrumental resolving power: 1,300,000 (NIR) and 10,000 (FIR)) with the Bruker 125HR Fourier transform spectrometer at JPL using isotopically-enriched 12CH4 and 13CH4, as well as normal methane samples. For the NIR wavelengths, three different absorption cells have been employed to achieve sample temperatures ranging from 78 K to 299 K: 1) a White cell set to a path length of 13.09 m for room temperature data, 2) a single-pass 0.2038 m cold cell and 3) a new coolable Herriott cell with a fixed 20.941 m optical path and configured for the first time to a FT-IR spectrometer. For the Far-IR, another coolable absorption chamber set to a 52 m optical path has been used. These new experiments and intensity measurements will be presented and discussed.Part of the research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, the University of California, Berkeley, Connecticut College, and NASA Langley under contracts and grants with the National Aeronautics and Space Administration. A. Predoi-Cross and her research group have been supported by the National Science and Engineering Research Council of Canada.

  8. Measurements of the intercombination and forbidden lines from helium-like ions in Tokamaks and Electron Beam Ion Traps

    SciTech Connect

    Bitter, M; Hill, K W; von Goeler, S; Stodiek, W; Beiersdorfer, P; Rice, J E; Ince-Cushman, A

    2007-08-22

    The paper reviews the results from tokamak experiments for the line ratios x/w, y/w, and z/w from helium-like ions with Z in the range from 14 to 28. With exception of the DITE experiments, where these line ratios were found to be in agreement with theoretical predictions, all other tokamak experiments yielded values that were significantly larger than predicted. The reasons for these discrepancies are not yet understood. It is possible that radial profile effects were not properly taken into account in the majority of the tokamak experiments. The paper also gives a short historical review of the X-ray diagnostic developments and also presents very recent data from a new type of X-ray imaging crystal spectrometer, which records spatially resolved spectra with a spatial resolution of about 1 cm in the plasma. These new data can be Abel inverted, so that it will be possible to determine line ratios at each radial position in the plasma. Effects of radial profiles, which may have affected the chord-integrated measurements of the past, will thus be eliminated in the future.

  9. Excitation of O(1D) atoms in aurorae and emission of the forbidden OI 6300-A line

    NASA Technical Reports Server (NTRS)

    Rees, M. H.; Roble, R. G.

    1986-01-01

    The electron aurora leads to six processes capable of exciting the O(1D2) metastable state of the atomic-oxygen ground-state configuration, the parent state of the 6300-A red line. Altitude profiles of the volume emission rate resulting from each process are computed for Maxwellian electron spectra with characteristic energies between 0.1 and 2.0 keV. Since each process peaks at a different altitude, the sum or total volume emission rate extends over a wide altitude range. Measurements of 6300-A emission obtained by rocket and satellite-borne instruments are summarized, and it is shown that the chemical reaction of N(2D) with O2 is the major source of O(1D) atoms in the electron aurora. New calculations of the 6300-A:4728-A column emission-rate ratio are presented for a range of characteristic energies in an assumed Maxwellian electron spectrum. An approximate equation for the red-line emission per unit energy input is given as a function of electron-spectrum characteristic energy.

  10. Forbidden Iron Lines and Dust Destruction in Supernova Remnant Shocks: The Case of N49 in the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Dopita, Michael A.; Seitenzahl, Ivo R.; Sutherland, Ralph S.; Vogt, Frédéric P. A.; Winkler, P. Frank; Blair, William P.

    2016-08-01

    We present the results of a complete integral-field survey of the bright supernova remnant (SNR) N49 in the Large Magellanic Cloud, obtained with the WiFeS instrument mounted on the ANU 2.3 m telescope at Siding Spring Observatory. From theoretical shock modeling with the new MAPPINGS 5.1 code, we have, for the first time, subjected the optical Fe emission line spectrum of an SNR to a detailed abundance and dynamical analysis covering eight separate stages of ionization. This allows us to derive the dust depletion factors as a function of ionization stage. We have shown that there is substantial (30%-90%) destruction of Fe-bearing dust grains in these fast shocks (v s ˜ 250 km s-1), and we have confirmed that the dominant dust destruction occurs through the non-thermal sputtering and grain-grain collision mechanisms developed in a number of theoretical works.

  11. The O(1S - 1D,3P) Line Intensity Ratio

    NASA Astrophysics Data System (ADS)

    Slanger, T. G.; Sharpee, B. D.; Cosby, P. C.; Minschwaner, K. R.; Siskind, D. E.

    2005-05-01

    The line intensity ratio of the two optically-forbidden atmospheric emissions, O(1S-1D) at 557.7 nm and O(1S-3P) at 297.2 nm, must be a single-valued number in the upper atmosphere because the upper level is common to both lines. The calculated transition probability ratio A(557.7)/A(297.2) is 16, by several authors, and the ratio found in the laboratory is significantly larger. Field observations require space-based instruments, in which case calibration between the two wavelengths is the critical issue. We circumvent this problem by using the O2 Herzberg I emission system as a bridge between the UV region below 310 nm and the ground-accessible region above that wavelength. These two spectral regions can be separately calibrated in terms of intensity, and the results of a disparate set of observations (satellite, rocket, ground-based) lead to A(557.7)/A(297.2) ratios that are consistently much smaller than the calculated value. These results have consequences for auroral and dayglow processes, and it is particularly important to ascertain the cause of the substantial difference between theory and observation.

  12. Gamma-ray line intensities for depleted uranium

    SciTech Connect

    Moss, C.E.

    1985-01-01

    Measurements of the gamma-ray line intensities from depleted uranium allowed us to determine which of two conflicting previous experiments was correct. For the 1001-keV line we obtain a branching ratio of 0.834 +- 0.007, in good agreement with one of the previous experiments. A table compares our intensities for several lines with those obtained in previous experiments. 5 refs., 2 figs., 1 tab.

  13. The Forbidden Quantum Adder

    NASA Astrophysics Data System (ADS)

    Alvarez-Rodriguez, U.; Sanz, M.; Lamata, L.; Solano, E.

    2015-07-01

    Quantum information provides fundamentally different computational resources than classical information. We prove that there is no unitary protocol able to add unknown quantum states belonging to different Hilbert spaces. This is an inherent restriction of quantum physics that is related to the impossibility of copying an arbitrary quantum state, i.e., the no-cloning theorem. Moreover, we demonstrate that a quantum adder, in absence of an ancillary system, is also forbidden for a known orthonormal basis. This allows us to propose an approximate quantum adder that could be implemented in the lab. Finally, we discuss the distinct character of the forbidden quantum adder for quantum states and the allowed quantum adder for density matrices.

  14. Critically Evaluated Energy Levels, Spectral Lines, Transition Probabilities, and Intensities of Singly Ionized Vanadium (V ii)

    NASA Astrophysics Data System (ADS)

    Saloman, Edward B.; Kramida, Alexander

    2017-08-01

    The energy levels, observed spectral lines, and transition probabilities of singly ionized vanadium, V ii, have been compiled. The experimentally derived energy levels belong to the configurations 3d 4, 3d 3 ns (n = 4, 5, 6), 3d 3 np, and 3d 3 nd (n = 4, 5), 3d 34f, 3d 24s 2, and 3d 24s4p. Also included are values for some forbidden lines that may be of interest to the astrophysical community. Experimental Landé g-factors and leading percentages for the levels are included when available, as well as Ritz wavelengths calculated from the energy levels. Wavelengths and transition probabilities are reported for 3568 and 1896 transitions, respectively. From the list of observed wavelengths, 407 energy levels are determined. The observed intensities, normalized to a common scale, are provided. From the newly optimized energy levels, a revised value for the ionization energy is derived, 118,030(60) cm-1, corresponding to 14.634(7) eV. This is 130 cm-1 higher than the previously recommended value from Iglesias et al.

  15. Stark Widths Of Ionized Xenon UV Lines Of Low Intensity

    SciTech Connect

    Cirisan, M.; Djurovic, S.; Pelaez, R. J.; Aparicio, J. A.; Mar, S.

    2007-04-23

    Stark width measurements of several low intensity Xe II spectral lines (5d - 4f transitions) in UV region, are presented here for the first time. These measurements were obtained from helium - xenon pulsed arc plasma.

  16. Line intensities: the good, the bad and the ugly

    NASA Technical Reports Server (NTRS)

    Brown, L. R.

    2000-01-01

    Atmospheric remote sensing requires that line intensities be measured and modeled to 5 percent or better in laboratory studies. Successes and failures for analyses of carbon monoxide, methane, methanol and nitric acid will be reviewed.

  17. Observation of forbidden C II 158 micron emission from the diffuse interstellar medium at high Galactic latitude

    NASA Technical Reports Server (NTRS)

    Bock, J. J.; Hristov, V. V.; Kawada, M.; Matsuhara, H.; Matsumoto, T.; Matsuura, S.; Mauskopf, P. D.; Richards, P. L.; Tanaka, M.; Lange, A. E.

    1993-01-01

    We report the first detection of forbidden C II 158 micron line emission from the diffuse interstellar medium at high Galactic latitude. We have measured the integrated line intensity in a 36 arcmin field of view along a triangular scan path in a 5 x 20 deg region in Ursa Major using a rocket-borne, liquid-helium-cooled spectrophotometer. The scan included high-latitude infrared cirrus, molecular clouds, a bright external galaxy, M82, and the H I Hole, which is a region of uniquely low neutral hydrogen column density. Emission from forbidden C II is observed in all regions, and, in the absence of appreciable CO emission, it is well correlated with neutral hydrogen column density. We observe a forbidden C II gas cooling rate which varies from (1.18 +/- 0.4 to 3.25 +/- 0.8) x 10 exp -26 ergs/s/H atom. Regions with CO emission have enhanced forbidden C II line emission over that expected from the correlation with neutral hydrogen column density. We measure a line-to-continuum ratio which varies from 0.002 to 0.008 in comparison with the all-sky average of 0.0082 reported by FIRAS, which is heavily weighted toward the Galactic plane.

  18. [Physical meaning of temperature measured by spectral line intensity method].

    PubMed

    Zhao, Wen-Hua; Tang, Huang-Zai; Shen, Yan; Shi, Yong; Hou, Ling-Yun

    2007-11-01

    The difference between electron temperature and excitation temperature is analyzed in the aspect of statistics thermodynamics. It is presented clearly that the temperature acquired by spectral line intensity method is not free electron temperature, but internal electronic excitation temperature of heavy particle. Under thermal equilibrium condition, the excitation temperature is equal to the electron temperature, while under non-thermal equilibrium condition, the excitation temperature is not equal to the electron temperature. In the study of arc jet plume in vacuum chamber, spectral line intensity method was employed to measure the apparent excitation temperature of arc jet plume, and Langmuir probe was employed to measure the electron temperature of arcjet plume. The big difference between the excitation temperature and the electron temperature proved that the temperature acquired by spectral line intensity method is not free electron temperature.

  19. Sharp intense line in the bioluminescence emission of the firefly.

    PubMed

    Barua, A Gohain; Sharma, U; Phukan, M; Hazarika, S

    2014-06-01

    Numerous investigations have been carried out on the spectral distribution of the light of different species of fireflies. Here we record the emission spectrum of the Indian species of the firefly Luciola praeusta Kiesenwetter 1874 (Coleoptera : Lampyridae : Luciolinae) on a color film. Green and red color-sectors, with an intense yellow one in between, appear in this spectrum. Intensity profile of this spectrum reveals a hitherto undetected strong narrow yellow line, which lies within the full-width-at-half maximum (FWHM) of the intensity profile. The spectrum recorded in a high-resolution spectrometer confirms the presence of this sharp intense line. This finding lends support to an earlier drawn analogy between the in vivo emission of the firefly and laser light.

  20. Accurate line intensities of methane from first-principles calculations

    NASA Astrophysics Data System (ADS)

    Nikitin, Andrei V.; Rey, Michael; Tyuterev, Vladimir G.

    2017-10-01

    In this work, we report first-principle theoretical predictions of methane spectral line intensities that are competitive with (and complementary to) the best laboratory measurements. A detailed comparison with the most accurate data shows that discrepancies in integrated polyad intensities are in the range of 0.4%-2.3%. This corresponds to estimations of the best available accuracy in laboratory Fourier Transform spectra measurements for this quantity. For relatively isolated strong lines the individual intensity deviations are in the same range. A comparison with the most precise laser measurements of the multiplet intensities in the 2ν3 band gives an agreement within the experimental error margins (about 1%). This is achieved for the first time for five-atomic molecules. In the Supplementary Material we provide the lists of theoretical intensities at 269 K for over 5000 strongest transitions in the range below 6166 cm-1. The advantage of the described method is that this offers a possibility to generate fully assigned exhaustive line lists at various temperature conditions. Extensive calculations up to 12,000 cm-1 including high-T predictions will be made freely available through the TheoReTS information system (http://theorets.univ-reims.fr, http://theorets.tsu.ru) that contains ab initio born line lists and provides a user-friendly graphical interface for a fast simulation of the absorption cross-sections and radiance.

  1. Spectral Line De-confusion in an Intensity Mapping Survey

    NASA Astrophysics Data System (ADS)

    Cheng, Yun-Ting; Chang, Tzu-Ching; Bock, James; Bradford, C. Matt; Cooray, Asantha

    2016-12-01

    Spectral line intensity mapping (LIM) has been proposed as a promising tool to efficiently probe the cosmic reionization and the large-scale structure. Without detecting individual sources, LIM makes use of all available photons and measures the integrated light in the source confusion limit to efficiently map the three-dimensional matter distribution on large scales as traced by a given emission line. One particular challenge is the separation of desired signals from astrophysical continuum foregrounds and line interlopers. Here we present a technique to extract large-scale structure information traced by emission lines from different redshifts, embedded in a three-dimensional intensity mapping data cube. The line redshifts are distinguished by the anisotropic shape of the power spectra when projected onto a common coordinate frame. We consider the case where high-redshift [C ii] lines are confused with multiple low-redshift CO rotational lines. We present a semi-analytic model for [C ii] and CO line estimates based on the cosmic infrared background measurements, and show that with a modest instrumental noise level and survey geometry, the large-scale [C ii] and CO power spectrum amplitudes can be successfully extracted from a confusion-limited data set, without external information. We discuss the implications and limits of this technique for possible LIM experiments.

  2. Measurement of electric fields in a helium micro-hollow cathode discharge by forbidden transitions

    NASA Astrophysics Data System (ADS)

    Namba, Shinichi; Maki, Daisuke; Takiyama, Ken

    2013-09-01

    Micro-hollow cathode discharges operated at high pressure has been attracting a great deal of interest for various application, such as, excimer light sources, medical/biological fields and microchemical reactor. In the plasmas, the electric (E) field in the sheath region plays an important role to generate and sustain the plasmas. In order to determine the E field in the He microplasma, the emissions of allowed (He I 2P-4D: 492.19 nm) and forbidden (2P-4F: 492.06 nm) lines were observed. The cathode and anode were both made of brass, and ceramic disks were used to electrically insulate the electrodes. The cathode disk had inner hole diameter of 1.0 mm (length: 2.0 mm). The gas with a flow rate was 1.0 L/min. The discharge was operated at voltages of 250 V, currents of 8 mA and gas pressures up to 100 kPa. The plasmas in the cathode opening were observed using a visible spectrometer. The forbidden line associated with the level mixing of upper levels was observed in the cathode surface, indicating that the high E field was formed. As the intensity ratio of forbidden to the allowed lines is a function of the E field which is calculated by perturtabation theory, we derived the field strength of 18 kV/cm at 1.0 mm cathode surface.

  3. Ion source and injection line for high intensity medical cyclotron

    SciTech Connect

    Jia, XianLu Guan, Fengping; Yao, Hongjuan; Zhang, TianJue; Yang, Jianjun; Song, Guofang; Ge, Tao; Qin, Jiuchang

    2014-02-15

    A 14 MeV high intensity compact cyclotron, CYCIAE-14, was built at China Institute of Atomic Energy (CIAE). An injection system based on the external H− ion source was used on CYCIAE-14 so as to provide high intensity beam, while most positron emission tomography cyclotrons adopt internal ion source. A beam intensity of 100 μA/14 MeV was extracted from the cyclotron with a small multi-cusp H− ion source (CIAE-CH-I type) and a short injection line, which the H− ion source of 3 mA/25 keV H− beam with emittance of 0.3π mm mrad and the injection line of with only 1.2 m from the extraction of ion source to the medial plane of the cyclotron. To increase the extracted beam intensity of the cyclotron, a new ion source (CIAE-CH-II type) of 9.1 mA was used, with maximum of 500 μA was achieved from the cyclotron. The design and test results of the ion source and injection line optimized for high intensity acceleration will be given in this paper.

  4. Observations and modelling of line intensity ratios of OV multiplet lines for ? - ?

    NASA Astrophysics Data System (ADS)

    Kato, T.; Rachlew-Källne, E.; Hörling, P.; Zastrow, K.-D.

    1996-09-01

    Line intensity ratios of OV multiplet lines for the 0953-4075/29/18/019/img3 (J = 2,1,0) transitions are studied using a collisional radiative model and the results are compared with measurements from the reversed field pinch experiments Extrap T1 and T2 at KTH. The measured line intensity ratios deviate from the predictions of the model and the possible causes for the discrepancy are discussed with regard to errors in rate coefficients and non-quasi-steady state.

  5. Empowering line intensity mapping to study early galaxies

    NASA Astrophysics Data System (ADS)

    Comaschi, P.; Ferrara, A.

    2016-12-01

    Line intensity mapping is a superb tool to study the collective radiation from early galaxies. However, the method is hampered by the presence of strong foregrounds, mostly produced by low-redshift interloping lines. We present here a general method to overcome this problem which is robust against foreground residual noise and based on the cross-correlation function ψαL(r) between diffuse line emission and Lyα emitters (LAE). We compute the diffuse line (Lyα is used as an example) emission from galaxies in a (800 Mpc)3 box at z = 5.7 and 6.6. We divide the box in slices and populate them with 14 000(5500) LAEs at z = 5.7(6.6), considering duty cycles from 10-3 to 1. Both the LAE number density and slice volume are consistent with the expected outcome of the Subaru Hyper Suprime Cam survey. We add Gaussian random noise with variance σN up to 100 times the variance of the Lyα emission, σα, to simulate residual foregrounds and compute ψαL(r). We find that the signal-to-noise ratio of the observed ψαL(r) does not change significantly if σN ≤ 10σα and show that in these conditions the mean line intensity, ILyα, can be precisely recovered independently of the LAE duty cycle. Even if σN = 100σα, Iα can be constrained within a factor 2. The method works equally well for any other line (e.g. [C II], He II) used for the intensity-mapping experiment.

  6. Isoelectronic line intensity ratios for plasma electron temperature measurement (invited)

    NASA Astrophysics Data System (ADS)

    Marjoribanks, Robin S.; Budnik, Fredric; Kulcsár, Gábor; Zhao, Liang

    1995-01-01

    Strictly speaking, temperature is uniquely defined only in plasmas which are in complete thermodynamic equilibrium. In typical laser-produced plasmas, measurement of electron temperature amounts to a parametrization of some part of the distribution of electron energies, typically inferred from the recombination continuum, or from the ratio of spectral lines that are implicitly dependent on the electron distribution. Where the plasma is highly transient, suffers appreciable opacity, or is subject to a background radiation field, the interpretation of temperature from disparate spectral lines can become untrustworthy. For these complicated plasmas, a conceptually simpler spectral line diagnostic offers great advantages. A technique has been introduced that begins with plasmas that include two elements of similar atomic number, in a known ratio, and compares isoelectronic lines from ions that differ only in their nuclear charge Z, and thus in their ionization potentials χi. Since these two have different values of the same dimensionless parameter Te/χi, the ratio of intensities of isoelectronic lines can be interpreted to determine the temperature Te. The technique and its areas of advantage are described, the applications made to the special problems of laboratories elsewhere are summarized, and this particular progress in application to laser plasmas produced by high-intensity picosecond pulses are reported here.

  7. The optically thin C III spectrum - Line and multiplet intensities

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1993-01-01

    C III line/multiplet intensities expected under optically thin conditions are presented over the density/ temperature ranges 4.0 - 12.0 and 4.6 - 5.0 (40,000 - l00,000 K). These improved values are obtained from a hybrid level/term calculation which makes use of the most recently available atomic data and extends the treatment down to lower densities than were achieved with our previous term representation. Some illustrative applications are given, including a brief description of the importance of the present data for interpretation of the strong C III line emission from carbon Wolf-Rayet stars.

  8. The optically thin C III spectrum - Line and multiplet intensities

    NASA Astrophysics Data System (ADS)

    Bhatia, A. K.; Kastner, S. O.

    1993-05-01

    C III line/multiplet intensities expected under optically thin conditions are presented over the density/ temperature ranges 4.0 - 12.0 and 4.6 - 5.0 (40,000 - l00,000 K). These improved values are obtained from a hybrid level/term calculation which makes use of the most recently available atomic data and extends the treatment down to lower densities than were achieved with our previous term representation. Some illustrative applications are given, including a brief description of the importance of the present data for interpretation of the strong C III line emission from carbon Wolf-Rayet stars.

  9. The optically thin C III spectrum - Line and multiplet intensities

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1993-01-01

    C III line/multiplet intensities expected under optically thin conditions are presented over the density/ temperature ranges 4.0 - 12.0 and 4.6 - 5.0 (40,000 - l00,000 K). These improved values are obtained from a hybrid level/term calculation which makes use of the most recently available atomic data and extends the treatment down to lower densities than were achieved with our previous term representation. Some illustrative applications are given, including a brief description of the importance of the present data for interpretation of the strong C III line emission from carbon Wolf-Rayet stars.

  10. Interpreting The Unresolved Intensity Of Cosmologically Redshifted Line Radiation

    NASA Technical Reports Server (NTRS)

    Switzer, E. R.; Chang, T.-C.; Masui, K. W.; Pen, U.-L.; Voytek, T. C.

    2016-01-01

    Intensity mapping experiments survey the spectrum of diffuse line radiation rather than detect individual objects at high signal-to-noise ratio. Spectral maps of unresolved atomic and molecular line radiation contain three-dimensional information about the density and environments of emitting gas and efficiently probe cosmological volumes out to high redshift. Intensity mapping survey volumes also contain all other sources of radiation at the frequencies of interest. Continuum foregrounds are typically approximately 10(sup 2)-10(Sup 3) times brighter than the cosmological signal. The instrumental response to bright foregrounds will produce new spectral degrees of freedom that are not known in advance, nor necessarily spectrally smooth. The intrinsic spectra of fore-grounds may also not be well known in advance. We describe a general class of quadratic estimators to analyze data from single-dish intensity mapping experiments and determine contaminated spectral modes from the data themselves. The key attribute of foregrounds is not that they are spectrally smooth, but instead that they have fewer bright spectral degrees of freedom than the cosmological signal. Spurious correlations between the signal and foregrounds produce additional bias. Compensation for signal attenuation must estimate and correct this bias. A successful intensity mapping experiment will control instrumental systematics that spread variance into new modes, and it must observe a large enough volume that contaminant modes can be determined independently from the signal on scales of interest.

  11. INTERPRETING THE UNRESOLVED INTENSITY OF COSMOLOGICALLY REDSHIFTED LINE RADIATION

    SciTech Connect

    Switzer, E. R.; Chang, T.-C.; Pen, U.-L.; Voytek, T. C.

    2015-12-10

    Intensity mapping experiments survey the spectrum of diffuse line radiation rather than detect individual objects at high signal-to-noise ratio. Spectral maps of unresolved atomic and molecular line radiation contain three-dimensional information about the density and environments of emitting gas and efficiently probe cosmological volumes out to high redshift. Intensity mapping survey volumes also contain all other sources of radiation at the frequencies of interest. Continuum foregrounds are typically ∼10{sup 2}–10{sup 3} times brighter than the cosmological signal. The instrumental response to bright foregrounds will produce new spectral degrees of freedom that are not known in advance, nor necessarily spectrally smooth. The intrinsic spectra of foregrounds may also not be well known in advance. We describe a general class of quadratic estimators to analyze data from single-dish intensity mapping experiments and determine contaminated spectral modes from the data themselves. The key attribute of foregrounds is not that they are spectrally smooth, but instead that they have fewer bright spectral degrees of freedom than the cosmological signal. Spurious correlations between the signal and foregrounds produce additional bias. Compensation for signal attenuation must estimate and correct this bias. A successful intensity mapping experiment will control instrumental systematics that spread variance into new modes, and it must observe a large enough volume that contaminant modes can be determined independently from the signal on scales of interest.

  12. Distribution of forbidden neutral carbon emission in the ring nebula (NGC 6720)

    NASA Technical Reports Server (NTRS)

    Jewitt, D. C.; Danielson, G. E.; Kupferman, P. N.; Maran, S. P.

    1983-01-01

    The spatial distribution of forbidden C I 9823, 9850 A emission in NGC 6720 is reported. Like forbidden O I, the forbidden C I radiation appears enhanced in the region of the bright filaments. A few percent of the carbon atoms in the filaments are neutral. The neutral fraction is consistent with ionization equilibrium calculations made under the assumption of complete shielding of direct stellar radiation by hydrogen. The observed carbon lines are excited by photoelectrons produced from hydrogen by the nebular diffuse radiation field. The forbidden C I observations confirm that the filaments in NGC 6720 are regions of locally enhanced shielding.

  13. Absolute intensity calibrations of solar K line profiles

    NASA Technical Reports Server (NTRS)

    Pasachoff, J., M.

    1971-01-01

    Individual K-line profiles from elements of fine structure on the surface of the sun are calibrated absolutely. The continuum calibrations of Labs and Neckel and of Houtgast and Namba are considered, and the average K-profile is scaled to that of White and Suemoto. The ranges of intensities across a high-resolution spectrogram are tabulated for various parts of the line profile. Although the spatially-averaged value for K3 of 4.2% of the continuum corresponds to a brightness temperature of 4155 deg K, minimum and maximum values were 3980 and 4360 K, respectively. Similarly, K2v ranges from 4200 to 4560 K, and K2r from 4180 to 4460 K in small elements about 1 arc sec across.

  14. Temporal intensity interferometry for characterization of very narrow spectral lines

    NASA Astrophysics Data System (ADS)

    Tan, P. K.; Kurtsiefer, C.

    2017-08-01

    Some stellar objects exhibit very narrow spectral lines in the visible range additional to their blackbody radiation. Natural lasing has been suggested as a mechanism to explain narrow lines in Wolf-Rayet stars. However, the spectral resolution of conventional astronomical spectrographs is still about two orders of magnitude too low to test this hypothesis. We want to resolve the linewidth of narrow spectral emissions in starlight. A combination of spectral filtering with single-photon-level temporal correlation measurements breaks the resolution limit of wavelength-dispersing spectrographs by moving the linewidth measurement into the time domain. We demonstrate in a laboratory experiment that temporal intensity interferometry can determine a 20-MHz-wide linewidth of Doppler-broadened laser light and identify a coherent laser light contribution in a blackbody radiation background.

  15. Modelling of intense line radiation from laser-produced plasmas

    SciTech Connect

    Lee, Yim T.; Gee, M.

    1990-04-01

    In this paper, we discuss modelling of Lyman-{alpha} (i.e. Ly-{alpha}) radiation emitted from laser-produced plasmas. We are interested in the application of one of these line radiations to pump a transition of an ion in a different plasma spatially separated from the emitting source. The interest is in perturbing the plasma rather than just probing it as in some backlighting experiments. As a result of pumping, the populations of certain excited levels are inverted. The resulting gain coefficients depend strongly on the population inversion density which in turn depends on the brightness of the pump radiation. As a result, we must produce an intense bright radiation source. In addition, to pump a transition effectively, we also need a pump line with a width larger than the mismatch of the resonance since the widths of the pumped transitions are rather narrow

  16. Spectral line intensity and polarization in gas-dusty medium

    NASA Astrophysics Data System (ADS)

    Silant'ev, N. A.; Alekseeva, G. A.; Novikov, V. V.

    2017-07-01

    We study the standard spectral line radiative transfer equation for media consisting of resonant atoms and non-resonant components (the dust grains and the atoms without considered spectral transition). Our goal is to study the intensity and polarization of the resonance radiation emerging from semi-infinite atmosphere. Using the known technique of resolvent matrices, we obtain the exact solution of vectorial radiative transfer equation for various sources of non-polarized radiation in semi-infinite atmosphere. Homogeneous, linear increasing and exponentially decreasing sources are considered. Recall, that' with the homogeneous sources correspond to the isothermal atmosphere and the exponential ones correspond to the incident radiation with different angles of inclination.

  17. Far-infrared spectroscopy of galaxies - The 158 micron C(+) line and the energy balance of molecular clouds

    NASA Astrophysics Data System (ADS)

    Crawford, M. K.; Genzel, R.; Townes, C. H.; Watson, D. M.

    1985-04-01

    Observations of the 158 microns fine-structure line of C(+) toward the nuclei of six gas-rich galaxies are presented. The observations are compared with observations of the CO J = 1-0 and H I 21 cm lines, observations of far-IR continuum emission, and observations of forbidden C II emission with the Galaxy. The forbidden C II line comes from dense, warm gas in UV-illuminated photodissociation regions at the surfaces of molecular clouds. This line is probably optically thin in all but the brightest of galactic sources. The variation of forbidden C II brightness from source to source and its ratio to the integrated infrared continuum intensity agree well with the theoretical prediction that UV absorption by dust controls the C(+) column density. The forbidden C II line is a tracer of molecular clouds, especially those near intense sources of UV radiation.

  18. Atomic Data and Spectral Line Intensities for Ne III

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Thomas, R. J.; Landi, E.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ne III. The configurations used are 2s(sup 2) 2p(sup 4),2s2p(sup 5),2s(sup 2) 2p(sup 3)3s, and 2s(sup 2)3p(sup 3)3d giving rise to 57 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies, 5, 10, 15, 20, and 25 Ry. Excitation rate coefficients are calculated by assuming a Maxwellian electron velocity distribution at an electron temperature of logT,(K)=5.0, corresponding to maximum abundance of Ne III. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8)-10(exp 14) per cubic centimeter. Relative spectral line intensities are calculated. Proton excitation rates between the lowest three levels have been included in the statistical equilibrium equations. The predicted Ne III line intensities are compared with SERTS rocket measurements of a solar active region and of a laboratory EUV light source.

  19. Atomic Data and Emission Line Intensities for CA VII

    NASA Technical Reports Server (NTRS)

    Landi, E.; Bhatia, A. K.

    2003-01-01

    In the present work we calculate energy levels, transition probabilities and electron-ion collisional excitation rates for the 3s(sup 2)3p(sup 2), 3s3p(sup 3) and 3s(sup 2)3p3d configurations of the silicon-like ion Ca VII. The total number of intermediate coupling levels considered is 27. Collision strengths are calculated at seven incident electron energies: 8, 10, 15, 20, 30,40 and 60 Ry, using the Distorted Wave approximation and a 5-configuration model. Excitation rate coefficients are calculated by assuming a Maxwellian distribution of velocities and are used to calculate level populations and line emissivities under the assumption of statistical equilibrium. Line intensity ratios are calculated and compared with observed values measured from SERTS and SOHO/CDS spectra. The diagnostic potential of Ca VII is demonstrated, with particular emphasis on the possibility to measure the Ne/Ca relative abundance through simultaneous observations of Ca VII and N VI lines. Ca VII proves to be an excellent tool for the study of the FIP effect in the solar transition region.

  20. Ft-Ir Measurements of NH_3 Line Intensities in the 60 - 550 CM-1 Using Soleil/ailes Beamline

    NASA Astrophysics Data System (ADS)

    Sung, Keeyoon; Yu, Shanshan; Pearson, John; Manceron, Laurent; Kwabia Tchana, F.; Pirali, Olivier

    2015-06-01

    Ammonia (NH_3) has been found ubiquitous, e.g., in the interstellar medium, low-mass stars, Jovian planets of our solar system, and possibly in the low temperature exoplanets. Their spectroscopic line parameters are essential in the accurate interpretation of the planetary and astrophysical spectra observed with Herschel, SOFIA, ALMA, and JWST. In our previous paper, the NH_3 line positions in the far-IR region were studied for the ground state and ν_2 in an unprecedented accuracy, which revealed significant deficiencies in the NH_3 intensities, for instance, some weak ΔK = 3 lines were predicted to be ~100 times stronger. Measurement of line intensity for these lines in a consistent manner is demanded because the ΔK = 3 forbidden lines are only way other than collisions and l-doubled states to excite NH_3 to K > 0 levels. Recalling that NH_3 transition lines in the high J and K up to 18 were detected toward the galactic center in the star forming region of Sgr B_2, their accurate intensity measurements are critical in explaining the observed high K excitation, which will provide insights into radiative-transfer vs.levels. The interaction between a large amplitude torsional motion and the hyperfine coupling may also lead to a less known hyperfine effect, the so-called magnetic spin-torsion coupling, which was first studied by Heuvel and Dymanus and which has not yet been conclusively evidenced. In this talk, the magnetic hyperfine structure of the non-rigid methanol molecule will be investigated experimentally and theoretically. 13 hyperfine patterns were recorded using two molecular beam microwave spectrometers. These patterns, along with previously recorded ones,^c were analyzed in an attempt to evidence the effects of the magnetic spin-torsion coupling. The theoretical approach setup to analyze the observed data accounts for the spin-torsion coupling, in addition to the familiar magnetic spin-rotation and spin-spin couplings, and relies on symmetry

  1. Solar Forbidden Oxygen, Revisited

    NASA Astrophysics Data System (ADS)

    Ayres, Thomas R.

    2008-10-01

    Recent large reductions in the solar oxygen abundance, based on synthesis of photospheric O I, OH, and CO absorptions with 3D convection models, have provoked consternation in the helioseismology community: the previous excellent agreement between measured p-mode oscillation frequencies and predictions based on the recommended epsilonO of a decade ago (680 parts per million [ppm] relative to hydrogen) unravels at the new low value (460 ppm). In an attempt to reconcile these conflicting results, the formation of pivotal [O I] λ6300, which is blended with a weak Ni I line, has been reconsidered, exploiting an alternative 3D model (albeit only a single temporal snapshot). And while there are several areas of agreement with the earlier [O I] studies of Allende Prieto, Asplund, and others, there is one crucial point of disagreement: the epsilonO derived here is significantly larger, 650 +/- 65 ppm (although at the expense of a ~30% weaker Ni I line than expected from the recommended nickel abundance). One innovation is a more robust treatment of the solar wavelengths: the balance between the components of the [O I] + Ni I blend is sensitive to velocity errors of only a few hundred m s-1. A second improvement is enforcement of a "continuum calibration" to ensure a self-consistent 3D temperature scale. Because of the renewed agreement between the linchpin tracer [O I] and seismic oxygen, the proposed downward slump of the solar metallicity and the perceived "oxygen crisis" now can be said to rest on less secure footings.

  2. Intensity Mapping with Carbon Monoxide Emission Lines and the Redshifted 21 cm Line

    NASA Astrophysics Data System (ADS)

    Lidz, Adam; Furlanetto, Steven R.; Oh, S. Peng; Aguirre, James; Chang, Tzu-Ching; Doré, Olivier; Pritchard, Jonathan R.

    2011-11-01

    We quantify the prospects for using emission lines from rotational transitions of the CO molecule to perform an "intensity mapping" observation at high redshift during the Epoch of Reionization (EoR). The aim of CO intensity mapping is to observe the combined CO emission from many unresolved galaxies, to measure the spatial fluctuations in this emission, and to use this as a tracer of large-scale structure at very early times in the history of our universe. This measurement would help determine the properties of molecular clouds—the sites of star formation—in the very galaxies that reionize the universe. We further consider the possibility of cross-correlating CO intensity maps with future observations of the redshifted 21 cm line. The cross spectrum is less sensitive to foreground contamination than the auto power spectra, and can therefore help confirm the high-redshift origin of each signal. Furthermore, the cross spectrum measurement would help extract key information about the EoR, especially regarding the size distribution of ionized regions. We discuss uncertainties in predicting the CO signal at high redshift, and discuss strategies for improving these predictions. Under favorable assumptions and feasible specifications for a CO survey mapping the CO(2-1) and CO(1-0) lines, the power spectrum of CO emission fluctuations and its cross spectrum with future 21 cm measurements from the Murchison Widefield Array are detectable at high significance.

  3. Atomic Data and Spectral Line Intensities for Ni XXI

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Landi, E.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ni XXI. The configurations used are 2s(sup 2)2p(sup 4), 2s2p(sup 5), 2p(sup 6), 2s(sup 2)2p(sup 3)3s, and 2s(sup 2)3p(sup 3)3d giving rise to 58 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies, 85, 170, 255, 340, and 425 Ry. Excitation rate coefficients are calculated by assuming a Maxwellian electron velocity distribution at an electron temperature of log T(sub e)(K)=6.9, corresponding to maximum abundance of Ni XXI. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities 10(exp 8)-10(exp 14) per cubic centimeter. Relative spectral line intensities are calculated. Proton excitation rates between the lowest three levels have been included in the statistical equilibrium equations. The predicted intensity ratios are compared with available observations.

  4. Image intensity normalisation by maximising the Siddon line integral in the joint intensity distribution space.

    PubMed

    Kalemis, A; Binnie, D M; Flower, M A; Ott, R J

    2009-12-01

    This paper presents a novel data-driven method for image intensity normalisation, which is a prerequisite step for any kind of image comparison. The method involves a novel application of the Siddon algorithm that was developed initially for fast reconstruction of tomographic images and is based on a linear normalisation model with either one or two parameters. The latter are estimated by maximising the line integral, computed using the Siddon algorithm, in the 2D joint intensity distribution space of image pairs. The proposed normalisation method, referred to as Siddon Line Integral Maximisation (SLIM), was compared with three other methodologies, namely background ratio (BAR) scaling, linear fitting and proportional scaling, using a large number of synthesised datasets. SLIM was also compared with BAR normalisation when applied to phantom data and two clinical examples. The new method was found to be more accurate and less biased than its counterparts for the range of characteristics selected for the synthesised data. These findings were in agreement with the results from the analysis of the experimental and clinical data.

  5. a Nonhydrostatic Modeling Analysis of AN Intense Midlatitude Squall Line.

    NASA Astrophysics Data System (ADS)

    Yang, Ming-Jen

    1995-01-01

    Nonhydrostatic modeling shows that the convective cells of a squall line, which occurred over Kansas and Oklahoma on 10-11 June 1985, behaves as gravity waves. In the simulation, the gust front generates a continuous low -level updraft. Updraft cells periodically break away from the gust-front updraft and move at their associated gravity -wave phase speeds. Linear theory shows that waves are trapped in the troposphere because of the strong decrease of Scorer parameter with height. Linear theory predicts the gravity-wave amplitudes, quadrature relations, and the gravity-wave periods. The stronger front-to-rear propagation mode dominates in the mature stage of the storm. The decrease of Scorer parameter with height encountered by the rearward propagating waves is a product of the storm circulation. The drop-off in Scorer parameter with height is a manifestation of the shear between ascending front-to-rear and descending rear-to-front flows of the squall-line system. The squall line produces an environment conducive to trapping rearward propagating gravity waves generated at the gust front. Numerical experiments show that the rear inflow and related aspects of storm structure are sensitive to hydrometer types, ice-phase microphysics, and the midlevel environmental humidity. Ice-phase microphysics is important for the model to produce realistic air motions and precipitation in the stratiform region. With the occurrence of heavy hailstones, there is no enhanced rear-to-front flow at the back edge of the storm. Evaporation is the most important latent cooling process determining the structure and strength of the descending rear inflow and the mesoscale downdraft. Latent cooling by melting snow enhances the strength of the rear -to-front flow at the back edge of storm and the intensity of mesoscale downdraft. Mesoscale downdraft is initiated above the rm 0^circC level by sublimational cooling. With the environmental midlevel moisture reduced by half, mesoscale downdrafts

  6. Effect of layered nanostructures on the linewidth of forbidden E2 transitions

    NASA Astrophysics Data System (ADS)

    Guzatov, D. V.; Klimov, V. V.

    2017-08-01

    In the framework of classical electrodynamics, analytical expressions are derived and investigated for the linewidth of forbidden E2 transitions in an atom (molecule) located near layered metal – dielectric nanostructures. It is shown that the radiation intensity at the forbidden transition during detection in the halfspace behind a layered nanostructure can significantly exceed the intensity during detection in the half-space where an atom (molecule) is located.

  7. Atomic Data and Spectral Line Intensities for Ni XV

    NASA Technical Reports Server (NTRS)

    Landi, E.; Bhatia, A. K.

    2011-01-01

    Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Ni XV.Weinclude in the calculations the 9 lowest configurations, corresponding to 126 fine structure levels: 3s23p2, 3s3p3, 3s23p3d, 3p4, 3s3p23d, and 3s2 3p4l with l =, s, p, d, f. Collision strengths are calculated at five incident energies for all transitions: 7.8, 18.5, 33.5, 53.5, and 80.2 Ry above the threshold of each transition. An additional energy, very close to the transition threshold, has been added, whose value is between 0.004 and 0.28 Ry depending on the levels involved. Calculations have been carried out using the Flexible Atomic Code and the distorted-wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates calculated in the present work, statistical equilibrium equations for level populations are solved at electron densities covering the 10(exp 8)-10(exp 14)/cu cm range and at an electron temperature of log T(sub e)(K) = 6.4, corresponding to the maximum abundance of Ni XV. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database.

  8. Atomic Data and Spectral Line Intensities for Ca IX

    NASA Technical Reports Server (NTRS)

    Landi, E.; Bhatia, A. K.

    2012-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ca IX. We include in the calculations the 33 lowest configurations in the n = 3, 4, 5 complexes, corresponding to 283 fine structure levels in the 3l3l ', 3l4l'' and 3l4l''' configurations, where l,l' = s, p, d, l '' = s, p, d, f and l''' = s, p, d, f, g. Collision strengths are calculated at five incident energies for all transitions: 5.8, 13.6, 24.2, 38.6 and 57.9 Ry above the threshold of each transition. An additional energy, very close to the transition threshold, has been added, whose value is between 0.0055 Ry and 0.23 Ry depending on the levels involved. Calculations have been carried out using the Flexible Atomic Code and the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates calculated in the present work, statistical equilibrium equations for level populations are solved at electron densities covering the 10(exp 8)-10(exp 14)/cubic cm range and at an electron temperature of log T(sub e)(K)=5.8, corresponding to the maximum abundance of Ca IX. Spectral line intensities are calculated, and their diagnostic relevance is discussed.

  9. Atomic Data and Spectral Line Intensities for Ni XV

    NASA Technical Reports Server (NTRS)

    Landi, E.; Bhatia, A. K.

    2011-01-01

    Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Ni XV.Weinclude in the calculations the 9 lowest configurations, corresponding to 126 fine structure levels: 3s23p2, 3s3p3, 3s23p3d, 3p4, 3s3p23d, and 3s2 3p4l with l =, s, p, d, f. Collision strengths are calculated at five incident energies for all transitions: 7.8, 18.5, 33.5, 53.5, and 80.2 Ry above the threshold of each transition. An additional energy, very close to the transition threshold, has been added, whose value is between 0.004 and 0.28 Ry depending on the levels involved. Calculations have been carried out using the Flexible Atomic Code and the distorted-wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates calculated in the present work, statistical equilibrium equations for level populations are solved at electron densities covering the 10(exp 8)-10(exp 14)/cu cm range and at an electron temperature of log T(sub e)(K) = 6.4, corresponding to the maximum abundance of Ni XV. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database.

  10. Atomic Data and Spectral Line Intensities for NI XVII

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Landi, E.

    2011-01-01

    Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Ni XVII. We include in the calculations the 23 lowest configurations, corresponding to 159 fine-structure levels: 3l3l', 3l4l0'' , and 3s5l0''' , with l,l' = s,p,d, l'' = s,p,d, f, and l''' = s,p,d. Collision strengths are calculated at five incident energies for all transitions at varying energies above the threshold of each transition. One additional energy, very close to the threshold of each transition, has also been included. Calculations have been carried out using the Flexible Atomic Code in the distorted wave approximation. Additional calculations have been performed with the University College London suite of codes for comparison. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8) - 10(exp 14) / cubic cm and at an electron temperature of logT(sub e)e(K) = 6.5, corresponding to the maximum abundance of Ni XVII. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database

  11. Atomic Data and Spectral Line Intensities for Ne III

    NASA Technical Reports Server (NTRS)

    Landi, E.; Bhartia, A. K.

    2004-01-01

    Electron impact collision strengths, energy levels, oscillator strengths, and spontaneous radiative decay rates are calculated for Ne III. The configurations used are 2s(sup 2)2p(sup 4), 2s2p(sup 5), 2p(sup 6), 2s(sup 2)2p(sup 3)3(sub s), 2s(sup 2)2p(sup 3)3p, and 2s(sup 2)2p(sup 3)3d giving rise to 86 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies, 5.2, 10, 15, 20 and 25 Ry. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8) - 10(exp 14)/cc at an electron temperature of logTe/K = 5.0, corresponding to maximum abundance of Ne III. Relative spectral line intensities are calculated.

  12. Atomic Data and Spectral Line Intensities for S XI

    NASA Technical Reports Server (NTRS)

    Landi, E.; Bhatia, A. K.

    2003-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for S XI. The configurations included are 2s(sup 2)2psup 2), 2s2p(sup 3), 2p(sup 4), 2s(sup 2)2p3l and 2s(sup 2)2p4l (I = s , p , d) giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies, 32, 60, 90, 120, and 150 Ry. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved: The effects of resonances, proton rates, photoexcitation and cascades on level populations have been investigate. The predicted S XI line intensities are compared with EUV and UV observations of the quiet and active Sun.

  13. Generation of intensity covariations of the oxygen green and red lines in the nightglow

    NASA Astrophysics Data System (ADS)

    Misawa, K.; Takeuchi, I.; Kato, Y.; Aoyama, I.

    1984-02-01

    The cause of intensity covariations of the oxygen green and red lines is studied. Intensity covariations are compared with the auroral-electrojet-activity index AE, the substorm Pi2, and the magnetogram. It is suggested that intensity covariations or double-intensity maxima of the red line occur in association with intense auroral substorms, and that they are the direct experimental evidences of Testud's theory (1973).

  14. Determination of vibration-rotation lines intensities from absorption Fourier spectra

    NASA Technical Reports Server (NTRS)

    Mandin, J. Y.

    1979-01-01

    The method presented allows the line intensities to be calculated from either their equivalent widths, heights, or quantities deduced from spectra obtained by Fourier spectrometry. This method has proven its effectiveness in measuring intensities of 60 lines of the molecule H2O with a precision of 10%. However, this method cannot be applied to isolated lines.

  15. Atomic Data and Spectral Line Intensities for Ni XI

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Landi, E.

    2010-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ni XI. We include in the calculations the 10 lowest configurations, corresponding to 164 fine structure levels: 3s(sup 2)3p(sup 6), 3s(sup 2)3p(sup 5)3d, 3s(sup 2)3p(sup 4)3d(sup 2), 3s3p(sup 6)3d, 3s(sup 2)3p(sup 5)4l and 3s3p6 4l with l =.s, p, d. Collision strengths are calculated at five incident energies for all transitions: 7.1, 16.8, 30.2, 48.7 and 74.1 Ry above the threshold of each transition. An additional energy, very close to the transition threshold, has been added, whose value is between 0.06 Ry and 0.25 Ry depending on the lower level. Calculations have been carried out using the Flexible Atomic Code and the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, combined with Close Coupling collision excitation rate coefficient available in the literature for the lowest 17 levels, statistical equilibrium equations for level populations are solved at electron densities covering the 10(exp 8)-10(exp 14) cu cm range and at an electron temperature of logT(sub c)(K)=6.1, corresponding to the maximum abundance of Ni XI. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database.

  16. Atomic Data and Spectral Line Intensities for CA XVII

    NASA Technical Reports Server (NTRS)

    Bhatia, A.K.; Landi, E.

    2007-01-01

    Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ca XVII. The configurations used are 2s(sup 2), 2s2p, 2p(sup 2), 2l3l', 214l' and 2s5l', with l = s,p and l' = s,p, d giving rise to 92 fine-structure levels in intermediate coupling. Collision strengths are calculated at seven incident energies (15, 30, 75, 112.5, 150, 187.5 and 225 Ry) for the transitions within the three lowest configurations corresponding to the 10 lowest energy levels, and five incident energies (75, 112.5, 150, 187.5 and 225 Ry) for transitions between the lowest five levels and the n = 3,4,5 configurations. Calculations have been carried out using the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, and R-Matrix results for the 2s2, 2s2p, 2p2 configurations available in the literature, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10(exp 8)-10(exp 14)/cu cm at an electron temperature of log Te(K)=6.7, corresponding to the maximum abundance of Ca XVII. Spectral line intensities are calculated, and their diagnostic relevance L; discussed. This dataset will be made available in the next version of the CHIANTI database.

  17. Beau's lines and multiple periungueal pyogenic granulomas after long stay in an intensive care unit.

    PubMed

    Guhl, Guillermo; Torrelo, Antonio; Hernández, Angela; Zambrano, Antonio

    2008-01-01

    A child developed multiple Beau's lines and periungueal pyogenic granulomas after admission to the intensive care unit. Immobilization, hypoxia, and drugs might have acted as potential causative factors.

  18. Atomic data and line intensities for the S V ion

    NASA Astrophysics Data System (ADS)

    Iorga, C.; Stancalie, V.

    2017-05-01

    level population variations are the electron-impact collisional excitation and the radiative decay along with their inverse processes. As a result, the level populations along with the spectral high-line intensity ratios are provided.

  19. On the He/plus/ triplet line intensities.

    NASA Technical Reports Server (NTRS)

    Daltabuit, E.; Cox, D. P.

    1972-01-01

    Check of the adequacy of theoretical calculations of helium-triplet line strengths, including collisional enhancement, by comparing theoretical prediction with astronomical observations. It is shown that the observations of Peimbert and Torres-Peimbert (1971) and of Peimbert and Costero (1969) fit the theoretical predictions rather well, placing planetary nebulae and H II regions in separate density and temperature ranges. It appears that the theory of helium-triplet line strengths agrees with present observations.

  20. CALCULATION OF INTENSITY RATIOS OF OBSERVED INFRARED [Fe II] LINES

    SciTech Connect

    Deb, Narayan C.; Hibbert, Alan

    2010-03-10

    Two recent observational studies of the [Fe II] {lambda}12567/{lambda}16435 line ratio by Smith and Hartigan and Rodriguez-Ardila et al. have suggested that the available theoretical A-values could be incorrect to 10%-40%. We have carried out an extensive configuration interaction calculation of [Fe II] lines to investigate this claim, as well as the variability in observed line ratios for {lambda}8617/{lambda}9052 and {lambda}8892/{lambda}9227 of Dennefeld. For these transitions, we are generally in good agreement with the results of Nussbaumer and Storey, less so with those of Quinet et al. In comparison, the ratios derived from observations appear either to be less secure, or other factors influence those results.

  1. Far-infrared 14NH3 line positions and intensities measured with a FT-IR and AILES beamline, Synchrotron SOLEIL

    NASA Astrophysics Data System (ADS)

    Sung, Keeyoon; Yu, Shanshan; Pearson, John; Pirali, Olivier; Kwabia Tchana, Fridolin; Manceron, Laurent

    2016-09-01

    Extensive measurements of line positions and intensities are reported for the inversion-rotation and rovibrational transitions of 14NH3 in the 50-660 cm-1 region. This study analyzes high-resolution (0.00167 cm-1, unapodized) Fourier-transform spectra of high purity (99.5%) normal ammonia sample obtained using the AILES beamline of Synchrotron SOLEIL. The experimental conditions are designed to study transitions with intensities weaker than 1 × 10-22 cm-1/(molecule cm-2) at room temperature. Line positions and intensities of more than 2830 transitions of 14NH3 are measured and compiled after proper quality control; the features from minor isotopologues (15NH3 and NH2D) and H2O are identified and excluded. Based on the predictions of recent work from the empirical Hamiltonian modeling, systematic quantum assignments are made for 2047 transitions from eight bands including four inversion-rotation (gs, v2, 2v2, and v4) and four ro-vibrational bands (v2-gs, 2v2-v2, v4-v2, and 2v2-v4), as well as covering their ΔK = 3 forbidden transitions. The measured line positions for the assigned transitions are in an excellent agreement (typically better than 0.001 cm-1) with the predictions in a wide range of J and K for all the eight bands. The comparison with the HITRAN 2012 database is also satisfactory, although systematic offsets are seen for transitions with high J and K and those from weak bands. Also we note that out of the eight bands, the 2v2-v4 has not been listed in the HITRAN 2012 database. Differences of 20% are seen between our measured and calculated intensities depending on the bands. For line positions, greater differences are found for some NH3 bands in HITRAN 2012 than recent predictions. Measurements of the individual line positions and intensities are presented for the eight bands, and the final spectroscopic line positions and intensities are compiled as an electronic supplement.

  2. Spectrum line intensity as a surrogate for solar irradiance variations.

    PubMed

    Livingston, W C; Wallace, L; White, O R

    1988-06-24

    Active Cavity Radiometer Irradiance Monitor (ACRIM) solar constant measurements from 1980 to 1986 are compared with ground-based, irradiance spectrophotometry of selected Fraunhofer lines. Both data sets were identically sampled and smoothed with an 85-day running mean, and the ACRIM total solar irradiance (S) values were corrected for sunspot blocking (S(c)). The strength of the mid-photospheric manganese 539.4-nanometer line tracks almost perfectly with ACRIM S(e), Other spectral features formed high in the photosphere and chromosphere also track well. These comparisons independently confirm the variability in the ACRIM S(e), signal, indicate that the source of irradiance is faculae, and indicate that ACRIM S(e), follows the 11-year activity cycle.

  3. Forbidden patterns in financial time series.

    PubMed

    Zanin, Massimiliano

    2008-03-01

    The existence of forbidden patterns, i.e., certain missing sequences in a given time series, is a recently proposed instrument of potential application in the study of time series. Forbidden patterns are related to the permutation entropy, which has the basic properties of classic chaos indicators, such as Lyapunov exponent or Kolmogorov entropy, thus allowing to separate deterministic (usually chaotic) from random series; however, it requires fewer values of the series to be calculated, and it is suitable for using with small datasets. In this paper, the appearance of forbidden patterns is studied in different economical indicators such as stock indices (Dow Jones Industrial Average and Nasdaq Composite), NYSE stocks (IBM and Boeing), and others (ten year Bond interest rate), to find evidence of deterministic behavior in their evolutions. Moreover, the rate of appearance of the forbidden patterns is calculated, and some considerations about the underlying dynamics are suggested.

  4. Forbidden patterns in financial time series

    NASA Astrophysics Data System (ADS)

    Zanin, Massimiliano

    2008-03-01

    The existence of forbidden patterns, i.e., certain missing sequences in a given time series, is a recently proposed instrument of potential application in the study of time series. Forbidden patterns are related to the permutation entropy, which has the basic properties of classic chaos indicators, such as Lyapunov exponent or Kolmogorov entropy, thus allowing to separate deterministic (usually chaotic) from random series; however, it requires fewer values of the series to be calculated, and it is suitable for using with small datasets. In this paper, the appearance of forbidden patterns is studied in different economical indicators such as stock indices (Dow Jones Industrial Average and Nasdaq Composite), NYSE stocks (IBM and Boeing), and others (ten year Bond interest rate), to find evidence of deterministic behavior in their evolutions. Moreover, the rate of appearance of the forbidden patterns is calculated, and some considerations about the underlying dynamics are suggested.

  5. Electron impact excitation of Mg VIII . Collision strengths, transition probabilities and theoretical EUV and soft X-ray line intensities for Mg VIII

    NASA Astrophysics Data System (ADS)

    Grieve, M. F. R.; Ramsbottom, C. A.; Keenan, F. P.

    2013-08-01

    Context. Mg viii emission lines are observed in a range of astronomical objects such as the Sun, other cool stars and in the coronal line region of Seyfert galaxies. Under coronal conditions Mg viii emits strongly in the extreme ultraviolet (EUV) and soft X-ray spectral regions which makes it an ideal ion for plasma diagnostics. Aims: Two theoretical atomic models, consisting of 125 fine structure levels, are developed for the Mg viii ion. The 125 levels arise from the 2s22p, 2s2p2, 2p3, 2s23s, 2s23p, 2s23d, 2s2p3s, 2s2p3p, 2s2p3d, 2p23s, 2p23p and 2p23d configurations. Electron impact excitation collision strengths and radiative transition probabilities are calculated for both Mg viii models, compared with existing data, and the best model selected to generate a set of theoretical emission line intensities. The EUV lines, covering 312-790 Å, are compared with existing solar spectra (SERTS-89 and SUMER), while the soft X-ray transitions (69-97 Å) are examined for potential density diagnostic line ratios and also compared with the limited available solar and stellar observational data. Methods: The R-matrix codes Breit-Pauli RMATRXI and RMATRXII are utilised, along with the PSTGF code, to calculate the collision strengths for two Mg viii models. Collision strengths are averaged over a Maxwellian distribution to produce the corresponding effective collision strengths for use in astrophysical applications. Transition probabilities are also calculated using the CIV3 atomic structure code. The best data are then incorporated into the modelling code CLOUDY and line intensities generated for a range of electron temperatures and densities appropriate to solar and stellar coronal plasmas. Results: The present effective collision strengths are compared with two previous calculations. Good levels of agreement are found with the most recent, but there are large differences with the other for forbidden transitions. The resulting line intensities compare favourably with the

  6. Atomic Data and Spectral Line Intensities for Ne III

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Thomas, R. J.; Landi, E.; Fisher, Richard R. (Technical Monitor)

    2002-01-01

    A number of satellites and rockets have been launched to observe radiation from the Sun and other astrophysical objects. Line radiation is emitted when the electron impact excited levels decay to the lower levels by photon emission. From this radiation, the physical parameters such as electron temperature and density of the astrophysical plasma, elemental abundance, and opacity can be inferred. Ne III lines have been observed in H II regions, Ne-rich filaments in supernovae, and planetary nebulae. The allowed line at 489.50 Angstroms due to the transition 2s(sup 2) 2p(sup 5) (sup 3) P2 (goes to) 2s(sup 2)2p(sup 4)(sup 3)P2 has been identified in the solar spectrum by Vernazza and Reeves using Skylab observations. Other Ne III lines in the solar EUV spectrum have been reported by Thomas and Neupert based on observations from the Solar EUV Rocket Telescope and Spectrograph (SERTS) instrument. Atomic data for Ne III have been calculated by using a set of programs developed at, University College, London. The Superstructure and Distorted Wave (DW) programs have been updated over the years. In the Superstructure program, configuration interaction can be taken into account and radial functions are calculated in a modified Thomas-Fermi-Amaldi potential. This is a statistical potential and depends on parameters lambda 1 which are determined by optimizing the weighted sum of term energies. They are found to be lambda(sub 0)=1.2467, lambda(sub 1)=1.1617, and lambda(sub 2)=1.0663. The relativistic corrections are included by using the Breit-Pauli Hamiltonian as a perturbation to the nonrelativistic Hamiltonian. The same potential is used to calculate reactance matrices in the DW approximation in LS coupling. Collision strengths in intermediate coupling are obtained by using term coupling coefficients obtained from the Superstructure program. In this calculation, the configurations used are 2s(sup 2)2p(sup 4), 2s2p(sup 5), 2s(sup 2)2p(sup 3)3s, 2s(sup 2)p(sup 3)3d giving rise

  7. Expected intensities of solar neon-like ions

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1985-01-01

    A study of the expected intensities of the stronger solar neon-like ion emission lines, some not yet observed, is carried out to compare with the observational situation. The potential usefulness of the 2p5 3s(3P2) - 2p6 forbidden line as a density diagnostic is discussed, and new electric quadrupole lines in the soft X-ray range are noted. 'Observability diagrams' are presented as a convenient overview of the known and unobserved lines. The S VII resonance lines appear to have anomalous intensities.

  8. Room Temperature Line Lists for CO_2 Isotopologues with AB Initio Computed Intensities

    NASA Astrophysics Data System (ADS)

    Zak, Emil; Tennyson, Jonathan; Polyansky, Oleg; Lodi, Lorenzo; Zobov, Nikolay Fedorovich; Tashkun, Sergey; Perevalov, Valery

    2016-06-01

    We report 13 room temperature line lists for all major CO_2 isotopologues, covering 0-8000 wn. These line lists are a response to the need for line intensities of high, preferably sub-percent, accuracy by remote sensing experiments. Our scheme encompasses nuclear motion calculations supported by critical reliability analysis of the generated line intensities. Rotation-vibration wavefunctions and energy levels are computed using DVR3D and a high quality semi-empirical potential energy surface (PES) [1], followed by computation of intensities using a fully ab initio dipole moment surface (DMS). Cross comparison of line lists calculated using pairs of high-quality PES's and DMS's is used to assess imperfections in the PES, which lead to unreliable transition intensities between levels involved in resonance interactions. Four line lists are computed for each isotopologue to quantify sensitivity to minor distortions of the PES/DMS. This provides an estimate of the contribution to the overall line intensity error introduced by the underlying PES. Reliable lines are benchmarked against recent state-of-the-art measurements [2] and HITRAN-2012 supporting the claim that the majority of line intensities for strong bands are predicted with sub-percent accuracy [3]. Accurate line positions are generated using an effective Hamiltonian [4]. We recommend use of these line lists for future remote sensing studies and inclusions in databases. X. Huang, D. W. Schwenke, S. A. Tashkun, T. J. Lee, J. Chem. Phys. 136, 124311, 2012. O. L. Polyansky, K. Bielska, M. Ghysels, L. Lodi, N. F. Zobov, J. T. Hodges, J. Tennyson, PRL, 114, 243001, 2015. E. Zak, J. Tennyson, O. L. Polyansky, L. Lodi, S. A. Tashkun, V. I. Perevalov, JQSRT, in press and to be submitted. S. A. Tashkun, V. I. Perevalov, R. R. Gamache, J. Lamouroux, JQSRT, 152, 45-73, 2015.

  9. The safety of obstetric acupuncture: forbidden points revisited

    PubMed Central

    2015-01-01

    Background/aim Although the safety of acupuncture per se in pregnancy is reasonably well accepted, there remains debate regarding needling at points historically considered to be ‘forbidden’ during pregnancy. This article reviews the scientific literature on this topic. Main findings There is no objective evidence of harm following needling at forbidden points, summarised by the following four lines of evidence. (1) In 15 clinical trials (n=823 women receiving n=4549–7234 acupuncture treatments at one or more forbidden points) rates of preterm birth (PTB) and stillbirth following are equivalent to those in untreated control groups and consistent with background rates of these complications in the general population. (2) Observational studies, including a large cohort of 5885 pregnant women needled at forbidden points at all stage of pregnancy, demonstrate that rates of miscarriage, PTB, preterm prelabour rupture of membranes (PPROM), and preterm contractions (preterm labour (PTL) or threatened PTL) are comparable with untreated controls and/or consistent with their anticipated incidence. (3) There is no reliable evidence that acupuncture/electroacupuncture (EA) can induce miscarriage/labour, even under otherwise favourable circumstances such as post-dates pregnancy or intrauterine fetal death. (4) Laboratory experiments using pregnant rats have demonstrated that repeated EA at forbidden points throughout gestation does not influence rates of post-implantation embryonic demise or cause miscarriage, fetal loss or resorption. Conclusions These findings are reassuring and will help individualised risk:benefit assessment before treating pregnant women. Given the numerous evidence-based indications for obstetric acupuncture and lack of evidence of harm, risk:benefit assessments will often fall in favour of treatment. PMID:26362792

  10. Catalogue of equivalent widths and line intensities for prominences observed during 1964-1965

    NASA Technical Reports Server (NTRS)

    Rakhubovskiy, A. S.

    1973-01-01

    The method of observation and processing of the prominence spectra are described briefly. The equivalent widths, central intensities, half-widths and Doppler halfwidths are presented of the emission lines of the prominences.

  11. Room temperature line lists for CO2 symmetric isotopologues with ab initio computed intensities

    NASA Astrophysics Data System (ADS)

    Zak, Emil J.; Tennyson, Jonathan; Polyansky, Oleg L.; Lodi, Lorenzo; Zobov, Nikolay F.; Tashkun, Sergei A.; Perevalov, Valery I.

    2017-03-01

    Remote sensing experiments require high-accuracy, preferably sub-percent, line intensities and in response to this need we present computed room temperature line lists for six symmetric isotopologues of carbon dioxide: 13C16O2, 14C16O2, 12C17O2, 12C18O2, 13C17O2 and 13C18O2, covering the range 0-8000 cm-1. Our calculation scheme is based on variational nuclear motion calculations and on a reliability analysis of the generated line intensities. Rotation-vibration wavefunctions and energy levels are computed using the DVR3D software suite and a high quality semi-empirical potential energy surface (PES), followed by computation of intensities using an ab initio dipole moment surface (DMS). Four line lists are computed for each isotopologue to quantify sensitivity to minor distortions of the PES/DMS. Reliable lines are benchmarked against recent state-of-the-art measurements and against the HITRAN2012 database, supporting the claim that the majority of line intensities for strong bands are predicted with sub-percent accuracy. Accurate line positions are generated using an effective Hamiltonian. We recommend the use of these line lists for future remote sensing studies and their inclusion in databases.

  12. Anomalous Line Shifts From Local Intensity Gradients on the Soho/cds NIS Detector

    NASA Astrophysics Data System (ADS)

    Haugan, S. V. H.

    1999-04-01

    Line shifts for some emission lines on the SOHO/CDS NIS detector appear to be strongly correlated with local intensity gradients along the slit in a way that seems impossible to explain with a physical solar model. Line widths also show a correlation with local intensity gradients. The most plausible instrumental explanation seems to be an elliptical, tilted point-spread function inducing the line shifts. A toy model demonstrating the essentials of the observed behaviour is presented. The effective point-spread function of the instrument appears to modify the line shape into something other than a Gaussian, leaving highly structured residuals after line fitting, including `ghost' images in some pixel planes. The cause of these effects is yet unknown, but they should warrant experiments on the engineering model to reproduce the observed effects, shedding light on the nature of the aberrations.

  13. 14NH_3 Line Positions and Intensities in the Far-Infrared Comparison of Ft-Ir Measurements to Empirical Hamiltonian Model Predictions

    NASA Astrophysics Data System (ADS)

    Sung, Keeyoon; Yu, Shanshan; Pearson, John; Pirali, Olivier; Kwabia Tchana, F.; Manceron, Laurent

    2016-06-01

    We have analyzed multiple spectra of high purity (99.5%) normal ammonia sample recorded at room temperatures using the FT-IR and AILES beamline at Synchrotron SOLEIL, France. More than 2830 line positions and intensities are measured for the inversion-rotation and rovibrational transitions in the 50 - 660 wn region. Quantum assignments were made for 2047 transitions from eight bands including four inversion-rotation bands (gs(a-s), νb{2}(a-s), 2νb{2}(a-s), and νb{4}(a-s)) and four ro-vibrational bands (νb{2} - gs, 2νb{2} - gs, νb{4} - νb{2}, and 2νb{2} -νb{4}), as well as covering more than 300 lines of ΔK = 3 forbidden transitions. Out of the eight bands, we note that 2νb{2} - νb{4} has not been listed in the HITRAN 2012 database. The measured line positions for the assigned transitions are in an excellent agreement (typically better than 0.001 wn) with the predictions from the empirical Hamiltonian model [S. Yu, J.C. Pearson, B.J. Drouin, et al.(2010)] in a wide range of J and K for all the eight bands. The comparison with the HITRAN 2012 database is also satisfactory, although systematic offsets are seen for transitions with high J and K and those from weak bands. However, differences of 20% or so are seen in line intensities for allowed transitions between the measurements and the model predictions, depending on the bands. We have also noticed that most of the intensity outliers in the Hamiltonian model predictions belong to transitions from gs(a-s) band. We present the final results of the FT-IR measurements of line positions and intensities, and their comparisons to the model predictions and the HITRAN 2012 database. Research described in this paper was performed at the Jet Propulsion Laboratory and California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration.

  14. Intensity Mapping of Hα, Hβ, [OII], and [OIII] Lines at z < 5

    NASA Astrophysics Data System (ADS)

    Gong, Yan; Cooray, Asantha; Silva, Marta B.; Zemcov, Michael; Feng, Chang; Santos, Mario G.; Dore, Olivier; Chen, Xuelei

    2017-02-01

    Intensity mapping is becoming a useful tool to study the large-scale structure of the universe through spatial variations in the integrated emission from galaxies and the intergalactic medium. We study intensity mapping of the {{H}}α 6563 \\mathringA , [O iii] 5007 Å, [O ii] 3727 Å, and {{H}}β 4861 \\mathringA lines at 0.8≤slant z≤slant 5.2. The mean intensities of these four emission lines are estimated using the observed luminosity functions (LFs), cosmological simulations, and the star formation rate density (SFRD) derived from observations at z≲ 5. We calculate the intensity power spectra and consider the foreground contamination of other lines at lower redshifts. We use the proposed NASA small explorer SPHEREx (the Spectro-Photometer for the History of the universe, Epoch of Reionization, and Ices Explorer) as a case study for the detectability of the intensity power spectra of the four emission lines. We also investigate the cross-correlation with the 21 cm line probed by the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Tianlai experiment and the Square Kilometer Array (SKA) at 0.8≤slant z≤slant 2.4. We find both the auto and cross power spectra can be well measured for the Hα, [O iii] and [O ii] lines at z≲ 3, while it is more challenging for the Hβ line. Finally, we estimate the constraint on the SFRD from intensity mapping, and find we can reach an accuracy higher than 7% at z≲ 4, which is better than with the usual method of measurements using the LFs of galaxies.

  15. Prevention of central venous line associated bloodstream infections in adult intensive care units: A systematic review.

    PubMed

    Velasquez Reyes, Diana Carolina; Bloomer, Melissa; Morphet, Julia

    2017-06-26

    In adult Intensive Care Units, the complexity of patient treatment requirements make the use of central venous lines essential. Despite the potential benefits central venous lines can have for patients, there is a high risk of bloodstream infection associated with these catheters. Identify and critique the best available evidence regarding interventions to prevent central venous line associated bloodstream infections in adult intensive care unit patients other than anti-microbial catheters. A systematic review of studies published from January 2007 to February 2016 was undertaken. A systematic search of seven databases was carried out: MEDLINE; CINAHL Plus; EMBASE; PubMed; Cochrane Library; Scopus and Google Scholar. Studies were critically appraised by three independent reviewers prior to inclusion. Nineteen studies were included. A range of interventions were found to be used for the prevention or reduction of central venous line associated bloodstream infections. These interventions included dressings, closed infusion systems, aseptic skin preparation, central venous line bundles, quality improvement initiatives, education, an extra staff in the Intensive Care Unit and the participation in the 'On the CUSP: Stop Blood Stream Infections' national programme. Central venous line associated bloodstream infections can be reduced by a range of interventions including closed infusion systems, aseptic technique during insertion and management of the central venous line, early removal of central venous lines and appropriate site selection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Unique forbidden beta decays and neutrino mass

    SciTech Connect

    Dvornický, Rastislav; Šimkovic, Fedor

    2015-10-28

    The measurement of the electron energy spectrum in single β decays close to the endpoint provides a direct determination of the neutrino masses. The most sensitive experiments use β decays with low Q value, e.g. KATRIN (tritium) and MARE (rhenium). We present the theoretical spectral shape of electrons emitted in the first, second, and fourth unique forbidden β decays. Our findings show that the Kurie functions for these unique forbidden β transitions are linear in the limit of massless neutrinos like the Kurie function of the allowed β decay of tritium.

  17. Line intensity enhancements in stellar coronal X-ray spectra due to opacity effects

    NASA Astrophysics Data System (ADS)

    Rose, S. J.; Matranga, M.; Mathioudakis, M.; Keenan, F. P.; Wark, J. S.

    2008-06-01

    Context: The I(15.01 Å)/I(16.78 Å) emission line intensity ratio in Fe xvii has been reported to deviate from its theoretical value in solar and stellar X-ray spectra. This is attributed to opacity in the 15.01 Å line, leading to a reduction in its intensity, and was interpreted in terms of a geometry in which the emitters and absorbers are spatially distinct. Aims: We study the I(15.01 Å)/I(16.78 Å) intensity ratio for the active cool dwarf EV Lac, in both flare and quiescent spectra. Methods: The observations were obtained with the Reflection Grating Spectrometer on the XMM-Newton satellite. The emission measure distribution versus temperature reconstruction technique is used for our analysis. Results: We find that the 15.01 Å line exhibits a significant enhancement in intensity over the optically thin value. To our knowledge, this is the first time that such an enhancement has been detected on such a sound statistical basis. We interpret this enhancement in terms of a geometry in which the emitters and absorbers are not spatially distinct, and where the geometry is such that resonant pumping of the upper level has a greater effect on the observed line intensity than resonant absorption in the line-of-sight.

  18. Nonlinear-resonance line shapes: Dependence on the transverse intensity distribution of a light beam

    SciTech Connect

    Taichenachev, A.V.; Yudin, V.I.; Wynands, R.; Kitching, J.; Hollberg, L.

    2004-02-01

    We analyze the line shape and width of atomic coherent-population-trapping (CPT) resonances excited by laser beams with different transverse intensity profiles. A dramatic difference in the resonance line shape is found when comparing a beam with a 'steplike' profile to a beam with a Gaussian profile. In particular, for nonuniform profiles, a non-Lorentzian functional form is given that is more appropriate for describing the nonlinear resonance line shape than is a conventional Lorentzian. Our analysis is supported by measurements of CPT line shapes in a thermal vapor of {sup 85}Rb.

  19. Line intensity measurements for acetylene between 8980 and 9420 cm-1

    NASA Astrophysics Data System (ADS)

    Béguier, S.; Lyulin, O. M.; Hu, S.-M.; Campargue, A.

    2017-03-01

    The absorption spectrum of acetylene is studied by high-resolution Fourier-transform spectroscopy (FTS) between 8980 and 9420 cm-1. Positions and intensities of 432 12C2H2 absorption lines are retrieved from a spectrum recorded at room temperature (298.5 K) with a pressure of 87.6 hPa and a 105 m path length. The measured lines belong to 11 bands including three bands observed for the first time. The obtained intensity dataset constitutes the first intensity information in the region. The Herman-Wallis coefficients are derived from a fit of the measured intensity values. The reported results will be valuable to complete the spectroscopic databases of acetylene.

  20. Operation of the intensity monitors in beam transport lines at Fermilab during Run II¹

    DOE PAGES

    Crisp, J.; Fellenz, B.; Fitzgerald, J.; ...

    2011-10-06

    The intensity of charged particle beams at Fermilab must be kept within pre-determined safety and operational envelopes in part by assuring all beam within a few percent has been transported from any source to destination. Beam instensity monitors with toroidial pickups provide such beam intensity measurements in the transport lines between accelerators at FNAL. With Run II, much effort was made to continually improve the resolution and accuracy of the system.

  1. Observation of Anomalous Intensity of EUV Lines during 2008-2010 Minimum of the Solar Cycle

    NASA Astrophysics Data System (ADS)

    Kazachevskaya, T. V.; Ivanov-Kholodny, G. S.

    2013-02-01

    The data processing and the measurements analysis of absolute intensity lines in solar irradiance in EUV spectra on satellites TIMED (27-190 nm with 0,1 nm resolution) and SOHO (lines 26-34 nm and 0,1-50 nm) in 2002-2011 have been carried out. The results of measurements show that during the period of minimum in the last solar cycle (2007-2009) the intensity of radiation in the lines of hydrogen H L-alpha (121.6 nm), helium and other ions are minimum. But line ion Neon intensity (Ne VI- Ne VIII I 43.6 - 77.03 nm ) and Oxygen ion lines: (OII - OVI 83.4 - 103.8 nm) in the cycle minimum increases and reaches its maximum in 2007-2008. The conclusion has been drown that while studying the effect of solar activity we should not probably consider only the Wolf number data, especially in the minimum phase. Now we see that there is some peculiarity in the process connected with the time of solar ultraviolet radiation intensity.

  2. Ratios of molecular hydrogen line intensities in shocked gas - Evidence for cooling zones

    NASA Technical Reports Server (NTRS)

    Brand, P. W. J. L.; Moorhouse, A.; Bird, M.; Burton, M. G.; Geballe, T. R.

    1988-01-01

    Column densities of molecular hydrogen have been calculated from 19 infrared vibration-rotation and pure rotational line intensities measured at peak 1 of the Orion molecular outflow. The run of column density with energy level is similar to a simple coolng zone model of the line-emitting region, but is not well fitted by predictions of C-shock models current in the literature.

  3. Ratios of molecular hydrogen line intensities in shocked gas - Evidence for cooling zones

    NASA Technical Reports Server (NTRS)

    Brand, P. W. J. L.; Moorhouse, A.; Bird, M.; Burton, M. G.; Geballe, T. R.

    1988-01-01

    Column densities of molecular hydrogen have been calculated from 19 infrared vibration-rotation and pure rotational line intensities measured at peak 1 of the Orion molecular outflow. The run of column density with energy level is similar to a simple coolng zone model of the line-emitting region, but is not well fitted by predictions of C-shock models current in the literature.

  4. The soft X-ray spectrum of Capella - Discovery of intense line emission

    NASA Technical Reports Server (NTRS)

    Cash, W.; Bowyer, S.; Charles, P. A.; Lampton, M.; Garmire, G.; Riegler, G.

    1978-01-01

    A soft X-ray spectrum of Capella has been obtained with the HEAO 1 satellite. Only models which include intense line emission at 0.85 keV can adequately explain the data. The spectrum is consistent with emission from an isothermal solar-abundance plasma with a temperature of 10.5 million (+ or - 2.8 million) K. It is also consistent with a blend of temperatures between 4 and 20 million K. The intensity of the X-ray emission is constant over 2 days and similar to the intensity observed by ANS.

  5. Absolute Line Intensities for the nu6 Band of H2O2.

    PubMed

    Klee; Winnewisser; Perrin; Flaud

    1999-05-01

    The purpose of this work was to obtain reliable absolute intensities for the nu6 band of H2O2. It was undertaken because strong discrepancies exist between the different nu6 band intensities which are presently available in the literature (A. Perrin, A. Valentin, J.-M. Flaud, C. Camy-Peyret, L. Schriver, A. Schriver, and P. Arcas, J. Mol. Spectrosc. 1995. 171, 358), (R. May, J. Quant. Radiat. Transfer 1991. 45, 267), and (R. L. Sams, personal communication). The method which was chosen in the present work was to measure simultaneously the far-infrared absorptions and the nu6 absorptions of H2O2. Consequently, Fourier transform spectra of H2O2 were recorded at Giessen in a spectral range (370-1270 cm-1) which covers both the R branch of the torsion-rotation band and the P branch of the nu6 band which appear at low and high wavenumbers, respectively. From the low wavenumber data, the partial pressure of H2O2 present in the cell during the recording of the spectra was determined by calibrating the observed absorptions in the torsion-rotation band with intensities computed using the permanent H2O2 dipole moment measured by Stark effect (A. Perrin, J.-M. Flaud, C. Camy-Peyret, R. Schermaul, M. Winnewisser, J.-Y. Mandin, V. Dana, M. Badaoui, and J. Koput, J. Mol. Spectrosc. 1996. 176, 287-296) and [E. A. Cohen and H. M. Pickett, J. Mol. Spectrosc. 1981. 87, 582-583). In the high frequency range, this value of the partial pressure of H2O2 was used to measure absolute line intensities in the nu6 band. Finally, the line intensities in the nu6 band were fitted using the theoretical methods described in detail in our previous works. Using these new results on line intensities together with the line position parameters that we obtained previously, a new synthetic spectra of the nu6 band was generated, leading to a total band intensity of 0.185 x 10(-16) cm-1/(molecule.cm-2) at 296 K. It has to be pointed out that the new line intensities agree to within the experimental

  6. a Rigorous Comparison of Theoretical and Measured Carbon Dioxide Line Intensities

    NASA Astrophysics Data System (ADS)

    Yi, Hongming; Fleisher, Adam J.; Gameson, Lyn; Zak, Emil J.; Polyansky, Oleg; Tennyson, Jonathan; Hodges, Joseph T.

    2017-06-01

    The ability to calculate molecular line intensities from first principles plays an increasingly important role in populating line-by-line spectroscopic databases because of its generality and extensibility to various isotopologues, spectral ranges and temperature conditions. Such calculations require a spectroscopically determined potential energy surface, and an accurate dipole moment surface that can be either fully ab initio or an effective quantity based on fits to measurements Following our recent work where we used high-precision measurements of intensities in the (30013 →00001) band of ^{12}C^{16}O_2 to bound the uncertainty of calculated line lists, here we carry out high-precision, frequency-stabilized cavity ring-down spectroscopy measurements in the R-branch of the ^{12}C^{16}O_2 (20012 →00001) band from J = 16 to 52. Gas samples consisted of 50 μmol mol^{-1} or 100 μmol mol^{-1} of nitrogen-broadened carbon dioxide with gravimetrically determined SI-traceable molar composition. We demonstrate relative measurement precision (Type A) at the 0.15 % level and estimate systematic (Type B) uncertainty contributions in % of: isotopic abundance 0.01; sample density, 0.016; cavity free spectral rang,e 0.03; line shape, 0.05; line interferences, 0.05; and carbon dioxide molar fraction, 0.06. Combined in quadrature, these components yield a relative standard uncertainty in measured line intensity less than 0.2 % for most observed transitions. These intensities differ by more than 2 % from those measured by Fourier transform spectroscopy and archived in HITRAN 2012 but differ by less than 0.5 % with the calculations of Zak et al. E. Zak et al., J. Quant. Spectrosc. Radiat. Transf. 177, (2016) 31. Huang et al., J. Quant. Spectrosc. Radiat. Transf. 130, (2013) 134. Tashkun et al., J. Quant. Spectrosc. Radiat. Transf. 152, (2015) 45.

  7. Long-term variations of the oxygen red 630 nm line nightglow intensity

    NASA Astrophysics Data System (ADS)

    Gudadze, N. B.; Didebulidze, G. G.; Javakhishvili, G. Sh.; Shepherd, M. G.; Vardosanidze, M. V.

    2007-02-01

    The long-term data set of total nightglow intensity of the oxygen red 630.0 nm line observed at Abastumani (41.8 degrees N, 42.8 degrees E) between 1957-1993 is investigated. The long-term trend and characteristic variations in solar radiation during an 11 year cycle of the red-line intensity are different after astronomical twilight (premidnight) and at midnight. The amplitude of deviation of the red-line intensity from its mean value at solar maximum and (or) minimum phase is greatest after astronomical twilight and decreases toward midnight. The long-term trend of these variations changes from its value about 0.74 R/year premidnight to its minimum negative value of about -1.92 R/year at and after midnight. This behavior of the long-term trend is considered as a possible result of an increase in electron density below the peak height (h(m)F2) of the ionospheric F2 layer and lowering of the height h(m)F2 after midnight predicted by the TIME-GCM model on the assumption of an increase in density of greenhouse gases in the lower atmosphere. The third-order regression equation (with different solar activity indices) is considered to be convenient for describing long-term variations in the mean annual red-line intensity.

  8. On Estimation of Contamination from Hydrogen Cyanide in Carbon Monoxide Line-intensity Mapping

    NASA Astrophysics Data System (ADS)

    Chung, Dongwoo T.; Li, Tony Y.; Viero, Marco P.; Church, Sarah E.; Wechsler, Risa H.

    2017-09-01

    Line-intensity mapping surveys probe large-scale structure through spatial variations in molecular line emission from a population of unresolved cosmological sources. Future such surveys of carbon monoxide line emission, specifically the CO(1-0) line, face potential contamination from a disjointed population of sources emitting in a hydrogen cyanide emission line, HCN(1-0). This paper explores the potential range of the strength of HCN emission and its effect on the CO auto power spectrum, using simulations with an empirical model of the CO/HCN–halo connection. We find that effects on the observed CO power spectrum depend on modeling assumptions but are very small for our fiducial model, which is based on current understanding of the galaxy–halo connection. Given the fiducial model, we expect the bias in overall CO detection significance due to HCN to be less than 1%.

  9. On Estimation of Contamination from Hydrogen Cyanide in Carbon Monoxide Line-intensity Mapping

    DOE PAGES

    Chung, Dongwoo T.; Li, Tony Y.; Viero, Marco P.; ...

    2017-08-31

    Here, line-intensity mapping surveys probe large-scale structure through spatial variations in molecular line emission from a population of unresolved cosmological sources. Future such surveys of carbon monoxide line emission, specifically the CO(1-0) line, face potential contamination from a disjointed population of sources emitting in a hydrogen cyanide emission line, HCN(1-0). This paper explores the potential range of the strength of HCN emission and its effect on the CO auto power spectrum, using simulations with an empirical model of the CO/HCN–halo connection. We find that effects on the observed CO power spectrum depend on modeling assumptions but are very small formore » our fiducial model, which is based on current understanding of the galaxy–halo connection. Given the fiducial model, we expect the bias in overall CO detection significance due to HCN to be less than 1%.« less

  10. Measurement of the radiative lifetime of the 2s(2)2p(4) (1)S(0) metastable level of neon; a study of forbidden transitions of astrophysical interest

    NASA Astrophysics Data System (ADS)

    Daw, Adrian Nigel

    The radiative lifetime of the 2s22 p4 1S0 metastable level of Ne2+ (Ne III) has been measured to be 223 +/- 11 ms at the 90% confidence level by observing the photons emitted at 1815 Å (181.5 nm) by a decaying population of 1 S0 Ne2+ ions stored in a radio frequency ion trap. This thesis describes the first use of a method to account for any ions lost from the trap and determine the radiative lifetime. Metastable ions were produced by electron bombardment of Ne gas, and rate coefficients for Ne2+ + Ne collisions were also determined. The lifetime measurement is in good agreement with recent calculated values, and has a lower uncertainty than the calculated values. This is the first lifetime measurement for an excited term of a ground configuration ion in the second row of the periodic table. The transition probabilities (A-values) for the forbidden transitions in the ground configurations of these ions are required for astrophysical spectral line intensity ratio diagnostics. Using calculated branching ratios, we estimate that, at the 90% confidence level, A(3P1 - 1S0) = 1.94 +/- 0.17 s-1 for the forbidden line of Ne III at 1815 Å, and A(1D2 - 1S0) = 2.55 +/- 0.19 s-1 for the forbidden line of Ne III at 3344 Å.

  11. Electron density profile measurements from hydrogen line intensity ratio method in Versatile Experiment Spherical Torus

    NASA Astrophysics Data System (ADS)

    Kim, YooSung; Shi, Yue-Jiang; Yang, Jeong-hun; Kim, SeongCheol; Kim, Young-Gi; Dang, Jeong-Jeung; Yang, Seongmoo; Jo, Jungmin; Oh, Soo-Ghee; Chung, Kyoung-Jae; Hwang, Y. S.

    2016-11-01

    Electron density profiles of versatile experiment spherical torus plasmas are measured by using a hydrogen line intensity ratio method. A fast-frame visible camera with appropriate bandpass filters is used to detect images of Balmer line intensities. The unique optical system makes it possible to take images of Hα and Hβ radiation simultaneously, with only one camera. The frame rate is 1000 fps and the spatial resolution of the system is about 0.5 cm. One-dimensional local emissivity profiles have been obtained from the toroidal line of sight with viewing dumps. An initial result for the electron density profile is presented and is in reasonable agreement with values measured by a triple Langmuir probe.

  12. Electron density profile measurements from hydrogen line intensity ratio method in Versatile Experimental Spherical Torus

    SciTech Connect

    Kim, YooSung; Shi, Yue-Jiang Yang, Jeong-hun; Kim, SeongCheol; Kim, Young-Gi; Dang, Jeong-Jeung; Yang, Seongmoo; Jo, Jungmin; Chung, Kyoung-Jae; Oh, Soo-Ghee; Hwang, Y. S.

    2016-11-15

    Electron density profiles of versatile experiment spherical torus plasmas are measured by using a hydrogen line intensity ratio method. A fast-frame visible camera with appropriate bandpass filters is used to detect images of Balmer line intensities. The unique optical system makes it possible to take images of H{sub α} and H{sub β} radiation simultaneously, with only one camera. The frame rate is 1000 fps and the spatial resolution of the system is about 0.5 cm. One-dimensional local emissivity profiles have been obtained from the toroidal line of sight with viewing dumps. An initial result for the electron density profile is presented and is in reasonable agreement with values measured by a triple Langmuir probe.

  13. The gamma 1 and gamma 3 bands of (16)O3: Line positions and intensities

    NASA Technical Reports Server (NTRS)

    Flaud, J.-M.; Camy-Peyret, C.; Devi, V. Malathy; Rinsland, C. P.; Smith, M. A. H.

    1988-01-01

    Using 0.005/cm-resolution Fourier transform spectra of samples of ozone, the gamma 1 and gamma 3 bands of (16)O3 have been reanalyzed to obtain accurate line positions and an extended set of upper state rotational levels (J up to 69, K sub a up to 20). Combined with the available microwave data, these upper state rotational levels were satisfactorily fitted using a Hamiltonian which takes explicitly into account the strong Coriolis interaction affecting the rotational levels of these two interacting states. In addition, 350 relative line intensities were measured from which the rotational expansions of the transition moment operators for the gamma 1 and gamma 3 states have been deduced. Finally, a complete listing of line positions, intensities, and lower state energies of the gamma 1 and gamma 3 bands of (16)O3 has been generated.

  14. Relation of the green coronal line intensity to sunspot areas and magnetic fields of different scales

    NASA Astrophysics Data System (ADS)

    Badalyan, O. G.; Bludova, N. G.

    2014-07-01

    The intensity of Fe XIV 530.3-nm green coronal line is compared quantitatively with the strength of magnetic fields of small and large scales and also with total sunspot areas for 1977-2001. A degree of similarity of appropriate synoptic maps is evaluated using correlation analysis. The green line intensity maps are constructed from data of its daily monitoring. Strengths of magnetic fields are calculated in a potential approximation using the photosphere observations of Wilcox Solar Observatory for a distance of 1.1 The calculations are performed separately for fields of large and small spatial scales. The total area of sunspots is obtained using data from the Greenwich Catalogue and its continuation by USAF/NOAA. The correlation has been calculated for the aggregate of areas (with a size of 20° in latitude and 30° in longitude) coinciding spatially on all maps. It is found that the most correlation between the green line intensity and coronal fields of small scales is observed in a zone of 0°-20°. The correlation with total sunspot areas (i.e., with local fields at the photosphere level) is substantially less here. In the higher-latitude zone 20°-40°, correlation of the green-line intensity with spot areas and small-scale coronal fields decreases. The large-scale fields have little influence on the green-line emission in the spot-formation zone. These results are the evidence of a complex nature of the effect of different-scale fields, arising as a result of dynamo activity in the subsurface (leptocline) and deep-lying (tachocline) layers of the convective zone, on the processes of the Sun's corona heating and green coronal line emission.

  15. Doppler cooling and trapping on forbidden transitions.

    PubMed

    Binnewies, T; Wilpers, G; Sterr, U; Riehle, F; Helmcke, J; Mehlstäubler, T E; Rasel, E M; Ertmer, W

    2001-09-17

    Ultracold atoms at temperatures close to the recoil limit have been achieved by extending Doppler cooling to forbidden transitions. A cloud of (40)Ca atoms has been cooled and trapped to a temperature as low as 6 microK by operating a magnetooptical trap on the spin-forbidden intercombination transition. Quenching the long-lived excited state with an additional laser enhanced the scattering rate by a factor of 15, while a high selectivity in velocity was preserved. With this method, more than 10% of precooled atoms from a standard magnetooptical trap have been transferred to the ultracold trap. Monte Carlo simulations of the cooling process are in good agreement with the experiments.

  16. INTENSITY ENHANCEMENT OF O VI ULTRAVIOLET EMISSION LINES IN SOLAR SPECTRA DUE TO OPACITY

    SciTech Connect

    Keenan, F. P.; Mathioudakis, M.; Doyle, J. G.; Madjarska, M. S.; Rose, S. J.; Bowler, L. A.; Britton, J.; McCrink, L.

    2014-04-01

    Opacity is a property of many plasmas. It is normally expected that if an emission line in a plasma becomes optically thick, then its intensity ratio to that of another transition that remains optically thin should decrease. However, radiative transfer calculations undertaken both by ourselves and others predict that under certain conditions the intensity ratio of an optically thick to an optically thin line can show an increase over the optically thin value, indicating an enhancement in the former. These conditions include the geometry of the emitting plasma and its orientation to the observer. A similar effect can take place between lines of differing optical depths. While previous observational studies have focused on stellar point sources, here we investigate the spatially resolved solar atmosphere using measurements of the I(1032 Å)/I(1038 Å) intensity ratio of O VI in several regions obtained with the Solar Ultraviolet Measurements of Emitted Radiation instrument on board the Solar and Heliospheric Observatory satellite. We find several I(1032 Å)/I(1038 Å) ratios observed on the disk to be significantly larger than the optically thin value of 2.0, providing the first detection (to our knowledge) of intensity enhancement in the ratio arising from opacity effects in the solar atmosphere. The agreement between observation and theory is excellent and confirms that the O VI emission originates from a slab-like geometry in the solar atmosphere, rather than from cylindrical structures.

  17. Examining Helium Line Intensities and Ratios in a Linear Helium Plasma to Identify Te and ne

    NASA Astrophysics Data System (ADS)

    Ray, H.; Biewer, T. M.; Unterberg, E. A.; Fehling, D. T.; Isler, R. C.

    2015-11-01

    Oak Ridge National Laboratory's prototype Material Plasma Exposure eXperiment (Proto-MPEX) is a linear plasma device dedicated to the understanding of plasma material interaction physics. A photomultiplier tube (PMT) based diagnostic system called a filterscope examines the visible light emission from Proto-MPEX. The filterscope is a non-invasive, high sensitivity, and high temporal resolution compact system with multiple PMT channels. Three PMTs contain He I narrow bandpass filters of wavelengths 667.9, 723.6, and 706.7 nm for line ratio analysis. Helium line intensities and ratios have been widely applied on astrophysical plasmas and machines such as JET and NSTX to determine profiles of electron temperatures, Te, and densities, ne. Ratios of the He I intensities measured by the filterscope are compared to calculated intensity ratios determined through a collisional radiative model (CRM) as follows: An excited He atom in state P will de-excite to a lower energy level Q by emitting a photon of a specific wavelength. A CRM uses the interactions P has with Q and other energy levels to calculate the population density of P. The calculated population density is used to determine the spectral line intensity of the wavelength analyzed. The aforementioned process is performed for each of the He I bandpass filters, and ratios dependent on Te and ne are calculated and compared to the filterscopes measured ratios. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725.

  18. Measurement of the profile and intensity of the solar He I lambda 584-A resonance line

    NASA Technical Reports Server (NTRS)

    Maloy, J. O.; Hartmann, U. G.; Judge, D. L.; Carlson, R. W.

    1978-01-01

    The intensity and profile of the helium resonance line at 584 A from the entire disk of the sun was investigated by using a rocket-borne helium-filled spectrometer and a curve-of-growth technique. The line profile was found to be accurately represented by a Gaussian profile with full width at half maximum of 122 + or - 10 mA, while the integrated intensity was measured to be 2.6 + or - 1.3 billion photons/s per sq cm at solar activity levels of F(10.7) = 90.8 x 10 to the -22nd per sq m/Hz and Rz = 27. The measured line width is in good agreement with previous spectrographic measurements, but the integrated intensity is larger than most previous photoelectric measurements. However, the derived line center flux of 20 + or - 10 billion photons/s per sq cm/A is in good agreement with values inferred from airglow measurements.

  19. Blood Cultures at Central Line Insertion in the Intensive Care Unit: Comparison with Peripheral Venipuncture▿

    PubMed Central

    Stohl, Sheldon; Benenson, Shmuel; Sviri, Sigal; Avidan, Alexander; Block, Colin; Sprung, Charles L.; Levin, Phillip D.

    2011-01-01

    Blood cultures are a key diagnostic test for intensive care unit (ICU) patients; however, contaminants complicate interpretations and lead to unnecessary antibiotic administration and costs. Indications for blood cultures and central venous catheter (CVC) insertions often overlap for ICU patients. Obtaining blood cultures under the strict sterile precautions utilized for CVC insertion might be expected to decrease culture contamination. This retrospective study compared the results of blood cultures taken at CVC insertion, at arterial line insertion, and from peripheral venipuncture in order to validate the advantage of CVC insertion cultures. Cultures from indwelling lines were excluded. Results of 14,589 blood cultures, including 2,736 (19%) CVC, 1,513 (10%) arterial line, and 10,340 (71%) peripheral cultures taken over 5.5 years in two ICUs (general and medical) were analyzed. CVC cultures were contaminated more frequently than arterial line or peripheral cultures (225/2,736 [8%] CVC, 48/1,513 [3%] arterial line, and 378/10,340 (4%) peripheral cultures [P < 0.001 for CVC versus peripheral and CVC versus arterial line cultures]). True pathogens were found more frequently in CVC insertion cultures (334/2,736 [12%] CVC, 155/1,513 [10%] arterial line, and 795/10,340 [8%] peripheral cultures [P < 0.001 for CVC versus peripheral cultures; P = 0.055 for CVC versus arterial line cultures; P < 0.001 for peripheral versus arterial line cultures]). Contamination and true-positive rates were similar for culture sets from the two ICUs for each given culture source. Despite superior sterile precautions, cultures taken at the time of central line insertion had a higher contamination rate than did either peripheral or arterial line blood cultures. This may be related to the increased manipulations required for CVC insertion. PMID:21525219

  20. Electron-impact Excitation Collision Strengths and Theoretical Line Intensities for Transitions in S III

    NASA Astrophysics Data System (ADS)

    Grieve, M. F. R.; Ramsbottom, C. A.; Hudson, C. E.; Keenan, F. P.

    2014-01-01

    We present Maxwellian-averaged effective collision strengths for the electron-impact excitation of S III over a wide range of electron temperatures of astrophysical importance, log Te (K) = 3.0-6.0. The calculation incorporates 53 fine-structure levels arising from the six configurations—3s 23p 2, 3s3p 3, 3s 23p3d, 3s 23p4s, 3s 23p4p, and 3s 23p4d—giving rise to 1378 individual lines and is undertaken using the recently developed RMATRX II plus FINE95 suite of codes. A detailed comparison is made with a previous R-matrix calculation and significant differences are found for some transitions. The atomic data are subsequently incorporated into the modeling code CLOUDY to generate line intensities for a range of plasma parameters, with emphasis on allowed ultraviolet extreme-ultraviolet emission lines detected from the Io plasma torus. Electron density-sensitive line ratios are calculated with the present atomic data and compared with those from CHIANTI v7.1, as well as with Io plasma torus spectra obtained by Far-Ultraviolet Spectroscopic Explorer and Extreme-Ultraviolet Explorer. The present line intensities are found to agree well with the observational results and provide a noticeable improvement on the values predicted by CHIANTI.

  1. Electron-impact excitation collision strengths and theoretical line intensities for transitions in S III

    SciTech Connect

    Grieve, M. F. R.; Ramsbottom, C. A.; Hudson, C. E.; Keenan, F. P.

    2014-01-01

    We present Maxwellian-averaged effective collision strengths for the electron-impact excitation of S III over a wide range of electron temperatures of astrophysical importance, log T{sub e} (K) = 3.0-6.0. The calculation incorporates 53 fine-structure levels arising from the six configurations—3s {sup 2}3p {sup 2}, 3s3p {sup 3}, 3s {sup 2}3p3d, 3s {sup 2}3p4s, 3s {sup 2}3p4p, and 3s {sup 2}3p4d—giving rise to 1378 individual lines and is undertaken using the recently developed RMATRX II plus FINE95 suite of codes. A detailed comparison is made with a previous R-matrix calculation and significant differences are found for some transitions. The atomic data are subsequently incorporated into the modeling code CLOUDY to generate line intensities for a range of plasma parameters, with emphasis on allowed ultraviolet extreme-ultraviolet emission lines detected from the Io plasma torus. Electron density-sensitive line ratios are calculated with the present atomic data and compared with those from CHIANTI v7.1, as well as with Io plasma torus spectra obtained by Far-Ultraviolet Spectroscopic Explorer and Extreme-Ultraviolet Explorer. The present line intensities are found to agree well with the observational results and provide a noticeable improvement on the values predicted by CHIANTI.

  2. Ultrasound line-by-line scanning method of spatial-temporal active cavitation mapping for high-intensity focused ultrasound.

    PubMed

    Ding, Ting; Zhang, Siyuan; Fu, Quanyou; Xu, Zhian; Wan, Mingxi

    2014-01-01

    This paper presented an ultrasound line-by-line scanning method of spatial-temporal active cavitation mapping applicable in a liquid or liquid filled tissue cavities exposed by high-intensity focused ultrasound (HIFU). Scattered signals from cavitation bubbles were obtained in a scan line immediately after one HIFU exposure, and then there was a waiting time of 2 s long enough to make the liquid back to the original state. As this pattern extended, an image was built up by sequentially measuring a series of such lines. The acquisition of the beamformed radiofrequency (RF) signals for a scan line was synchronized with HIFU exposure. The duration of HIFU exposure, as well as the delay of the interrogating pulse relative to the moment while HIFU was turned off, could vary from microseconds to seconds. The feasibility of this method was demonstrated in tap-water and a tap-water filled cavity in the tissue-mimicking gelatin-agar phantom as capable of observing temporal evolutions of cavitation bubble cloud with temporal resolution of several microseconds, lateral and axial resolution of 0.50 mm and 0.29 mm respectively. The dissolution process of cavitation bubble cloud and spatial distribution affected by cavitation previously generated were also investigated. Although the application is limited by the requirement for a gassy fluid (e.g. tap water, etc.) that allows replenishment of nuclei between HIFU exposures, the technique may be a useful tool in spatial-temporal cavitation mapping for HIFU with high precision and resolution, providing a reference for clinical therapy.

  3. Communication: Visible line intensities of the triatomic hydrogen ion from experiment and theory

    SciTech Connect

    Petrignani, Annemieke; Berg, Max H.; Grussie, Florian; Wolf, Andreas; Mizus, Irina I.; Zobov, Nikolai F.; Polyansky, Oleg L.; Tennyson, Jonathan; Pavanello, Michele; Adamowicz, Ludwik

    2014-12-28

    The visible spectrum of H{sub 3}{sup +} is studied using high-sensitivity action spectroscopy in a cryogenic radiofrequency multipole trap. Advances are made to measure the weak ro-vibrational transitions from the lowest rotational states of H{sub 3}{sup +} up to high excitation energies providing visible line intensities and, after normalisation to an infrared calibration line, the corresponding Einstein B coefficients. Ab initio predictions for the Einstein B coefficients are obtained from a highly precise dipole moment surface of H{sub 3}{sup +} and found to be in excellent agreement, even in the region where states have been classified as chaotic.

  4. Determination of the magnetic spin direction from the nuclear forward-scattering line intensities.

    PubMed

    Callens, R; L'abbé, C; Meersschaut, J; Serdons, I; Sturhahn, W; Toellner, T S

    2007-07-01

    An expression is derived for the line intensities in a nuclear forward-scattering energy spectrum that is obtained via a Fourier transformation of the time dependence of the wavefield. The calculation takes into account the coherent properties of the nuclear forward-scattering process and the experimental limitations on the observable time window. It is shown that, for magnetic samples, the spin direction can be determined from the ratios between the different lines in the energy spectrum. The theory is complemented with experimental results on alpha-iron.

  5. Communication: Visible line intensities of the triatomic hydrogen ion from experiment and theory

    NASA Astrophysics Data System (ADS)

    Petrignani, Annemieke; Berg, Max H.; Grussie, Florian; Wolf, Andreas; Mizus, Irina I.; Polyansky, Oleg L.; Tennyson, Jonathan; Zobov, Nikolai F.; Pavanello, Michele; Adamowicz, Ludwik

    2014-12-01

    The visible spectrum of H3 + is studied using high-sensitivity action spectroscopy in a cryogenic radiofrequency multipole trap. Advances are made to measure the weak ro-vibrational transitions from the lowest rotational states of H3 + up to high excitation energies providing visible line intensities and, after normalisation to an infrared calibration line, the corresponding Einstein B coefficients. Ab initio predictions for the Einstein B coefficients are obtained from a highly precise dipole moment surface of H3 + and found to be in excellent agreement, even in the region where states have been classified as chaotic.

  6. Does Velocity Redistribution Really Enhance the HE 304 A Line to Observed Intensities?

    NASA Technical Reports Server (NTRS)

    Jordan, Stuart; Andretta, Vincenzo; Garcia, Adriana; Brosius, Jeffrey; Behring, William

    1999-01-01

    Previous work by this group has demonstrated that small-scale nonthermal velocities probably play a significant role in enhancing the intensity of the He II 304 A line above values predicted by the static atmosphere NLTE theories, and more in conformity with Skylab and SOHO observations. This presentation briefly summarizes the evidence for this conclusion, emphasizing SOHO and correlated groundbased observations, of which examples are presented. However, in contrast to the previous studies, the tact taken here is more critical, asking the question "Can velocity redistribution fully explain the observations of the 304 A line, and what counter-indications and problems remain?" The conclusion reached is that, while velocity redistribution plays a significant role in the intensity enhancement, it may not be the whole story. Some other mechanism, associated with velocity filtration, may be at work.

  7. Absolute Line Intensities in the 2nu3 Band of 16O12C32S

    PubMed

    Bermejo; Domenech; Santos; Bouanich; Blanquet

    1997-09-01

    The strengths of 100 lines in the 2nu3 band of 16O12C32S have been measured at high resolution in the spectral range 4069-4118 cm-1, using a tunable difference-frequency laser spectrometer. These intensities were obtained by fitting Voigt profiles to the measured shapes of the lines. The vibrational transition moment [(2.141 ± 0.020) x 10(-2) D] and the absolute intensity (16.19 ± 0.24 cm-2 atm-1 at 296 K) of the 2nu3 band of 16O12C32S are determined from these linestrength measurements. Copyright 1997 Academic Press. Copyright 1997Academic Press

  8. Forbidden Ca 2 in the sun unmasked by way of Venus

    NASA Technical Reports Server (NTRS)

    Schorn, R. A.; Young, A. T.; Barker, E. S.

    1975-01-01

    Eleven high-dispersion spectra of Venus, taken with blue Doppler shifts have permitted the unmasking of the 7323.88A forbidden line of Ca II from terrestrial absorption. An equivalent width is obtained of 7.4 + or - 0.4mA for this line in integrated sunlight. Our value of W sub lambda is smaller than previous values and much more accurate. The HSRA solar model gives a solar calcium abundance of A sub Ca = 6.21.

  9. Line Positions and Intensities for the ν12 Band of 13C12CH_6

    NASA Astrophysics Data System (ADS)

    Devi, V. Malathy; Benner, D. Chris; Sung, Keeyoon; Crawford, Timothy J.; Mantz, Arlan; Smith, Mary Ann H.

    2014-06-01

    High-resolution, high signal-to-noise spectra of mono-substituted 13C-ethane (13C12CH_6) in the 12.2 μm region were recorded with a Bruker IFS 125HR Fourier transform spectrometer. The spectra were obtained for four sample pressures at three different temperatures between 130 and 208 K using a 99% 13C-enriched ethane sample contained in a 20.38-cm long coolable absorption cell. A multispectrum nonlinear least squares fitting technique was used to fit the same intervals in the four spectra simultaneously to determine line positions and intensities. Similar to our previous analyses of 12C_2H_6 spectra in this same region, constraints were applied to accurately fit each pair of doublet components arising from torsional Coriolis interaction of the excited ν12 = 1 state with the nearby torsional ν_6 = 3 state. Line intensities corresponding to each spectrum temperature (130 K, 178 K and 208 K) are reported for 1660 ν12 absorption lines for which the assignments are known, and integrated intensities are estimated as the summation of the measured values. The measured line positions and intensities (re-scaled to 296 K) are compared with values in recent editions of spectroscopic databases. K. Sung, A. W. Mantz, L. R. Brown, et al., J. Mol. Spectrosc., 162 (2010) 124-134. D. C. Benner, C. P. Rinsland, V. Malathy Devi, M. A. H. Smith and D. Atkins, JQSRT, 53 (1995) 705-721. V. Malathy Devi, C. P. Rinsland, D. Chris Benner, et al., JQSRT, 111 (2010) 1234-1251 V. Malathy Devi, D. Chris Benner, C. P. Rinsland, et al., JQSRT, 111 (2010) 2481-2504. Research described in this paper was performed at Connecticut College, the College of William and Mary, NASA Langley Research Center and the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration.

  10. Line Positions and Intensities of Monodeuterated Methane Between 2.2 and 2.5 Microns

    NASA Astrophysics Data System (ADS)

    Brown, Linda R.; Sung, K.; Nikitin, A. V.; Smith, M. H.; Mantz, A. W.; Tyuterev, V. G.; Rey, M.

    2012-10-01

    A new study of 12CH3D line positions and intensities was performed for the upper portion of the Enneadecad polyad between 4000 and 4550 cm-1. For this, FTIR spectra were recorded with D-enriched methane samples (at 80 K with a Bruker 125 IFS at 0.005 cm-1 resolution and at 291 K with the McMath-Pierce FTS at 0.011 cm-1 resolution, respectively). Line positions and intensities were retrieved by least square curve-fitting procedures and analyzed using the effective Hamiltonian and the effective Dipole moment expressed in terms of irreducible tensors operators adapted to symmetric top molecules. Initially, only the cold spectrum was used to identify quantum assignments and predict 12CH3D relative intensities in this region. Combining the two temperature datasets confirmed the assumed quantum assignments and also demonstrated the relative accuracies to be better than ±0.0002 cm-1 for line positions and at least ±6% for 1160 selected features. Including additional assignments from the room temperature spectra alone permitted 1362 line intensities of 12 bands (involving 23 vibrational symmetry components) to be reproduced with an RMS of 9%. Over 4085 selected positions for 12 bands were modeled to 0.008 cm-1. More work is needed to obtain a complete characterization of this complex polyad. This work is part of the ANR project "CH4@Titan" (ref: BLAN08-2_321467). Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, the NASA Langley Research Center and Connecticut College under contracts and grants with the National Aeronautics and Space Administration. We acknowledge the LEFE-CHAT INSU project APOA1 (CNRS, France); the Groupement de Recherche International SAMIA between CNRS (France), RFBR (Russia) and CAS (China).

  11. Line Intensities in the Far-Infrared Spectrum of H 2O 2

    NASA Astrophysics Data System (ADS)

    Perrin, A.; Flaud, J.-M.; Camy-Peyret, C.; Schermaul, R.; Winnewisser, M.; Mandin, J.-Y.; Dana, V.; Badaoui, M.; Koput, J.

    1996-04-01

    Using high resolution Fourier transform spectra (resolution 0.002 cm -1) recorded at the Instituto Ricerca Onde Electromagnetiche Firenze and at the Justus Liebig University Giessen, it has been possible to measure the relative intensities of lines in the far-infrared spectrum of H 2O 2in the 25-400 cm -1spectral region. These intensities were used as input data in a least-squares fit calculation in order to obtain the expansion parameters of the transition moment operator of the pure torsional-rotational transitions of H 2O 2. For these intensity calculations, the theoretical model takes into account the cos γ-type dependence of the dipole moment due to the large amplitude motion of the H atoms relative to the O-O bond, where 2γ is the torsion angle. The value of the dipole moment obtained from the fit of the observed intensities was then scaled to the value obtained from Stark effect measurements. Finally, a synthetic spectrum of the far infrared band of H 2O 2was generated, using the dipole moment expansion determined in this work for the line intensities and the parameters and the Hamiltonian matrix given in a previous analysis (C. Camy-Peyret, J.-M. Flaud, J. W. C. Johns, and M. Noel, J. Mol. Spectrosc.155,84-104 (1992)) for the line positions. In addition to the (Δ n= ±1, Δ Ka= ∓2) torsional-rotational resonances within the ground vibrational state, which are usually observed for H 2O 2, the Hamiltonian model takes explicitly into account both the vibration-rotation resonances involving the ground state and the v3= 1 vibrational state and the "staggering" effect which is due to the cispotential barrier.

  12. The holographic recording in photopolymer by excitation forbidden singlet-triplet transitions

    NASA Astrophysics Data System (ADS)

    Shelkovnikov, V. V.; Pen, E. F.; Russkich, V. V.; Vasiliev, E. V.; Kovalevsky, V. I.

    2006-05-01

    The possibility and features of the holographic recording by excitation of the forbidden singlet-triplet transitions are considered in the report. The experimental demonstration of the hologram recording on forbidden transition is carried out in thick photopolymer material sensitized by Erithrozine dye. The single hologram with diffraction efficiency DE=50% and 16 angle multiplexing hologram were recorded by irradiation of the low intensity He-Ne laser (632 nm) at high concentration of the sensitizing dye and at high optical density in allowed absorption band of dye. The growth of DE of transition hologram depending on the Kr+(647 nm) laser irradiation intensity of was studied. The observed linear dependence of the maximal rate of DE growth on the intensity of recording irradiation was explained by two steps-two photon excitation (T I<--S 0, T II<--T I) of the dye in the photopolymer samples.

  13. Intensity mapping across cosmic times with the Lyα line

    SciTech Connect

    Pullen, Anthony R.; Doré, Olivier; Bock, Jamie

    2014-05-10

    We present a quantitative model of Lyα emission throughout cosmic history and determine the prospects for intensity mapping spatial fluctuations in the Lyα signal. Since (1) our model assumes at z > 6 the minimum star formation required to sustain reionization and (2) is based at z < 6 on a luminosity function (LF) extrapolated from the few observed bright Lyα emitters, this should be considered a lower limit. Mapping the line emission allows probes of reionization, star formation, and large-scale structure (LSS) as a function of redshift. While Lyα emission during reionization has been studied, we also predict the postreionization signal to test predictions of the intensity and motivate future intensity mapping probes of reionization. We include emission from massive dark matter halos and the intergalactic medium (IGM) in our model. We find agreement with current, measured LFs of Lyα emitters at z < 8. However, diffuse IGM emission, not associated with Lyα emitters, dominates the intensity up to z ∼ 10. While our model is applicable for deep-optical or near-infrared observers like the James Webb Space Telescope, only intensity mapping will detect the diffuse IGM emission. We also construct a three-dimensional power spectrum model of the Lyα emission. Finally, we consider the prospects of an intensity mapper for measuring Lyα fluctuations while identifying interloper contamination for removal. Our results suggest that while the reionization signal is challenging, Lyα fluctuations can be an interesting new probe of LSS at late times when used in conjunction with other lines, e.g., Hα, to monitor low-redshift foreground confusion.

  14. INTENSITY MAPPING OF THE [C II] FINE STRUCTURE LINE DURING THE EPOCH OF REIONIZATION

    SciTech Connect

    Gong Yan; Cooray, Asantha; Silva, Marta; Santos, Mario G.; Bock, James; Bradford, C. Matt; Zemcov, Michael

    2012-01-20

    The atomic C II fine-structure line is one of the brightest lines in a typical star-forming galaxy spectrum with a luminosity {approx}0.1%-1% of the bolometric luminosity. It is potentially a reliable tracer of the dense gas distribution at high redshifts and could provide an additional probe to the era of reionization. By taking into account the spontaneous, stimulated, and collisional emission of the C II line, we calculate the spin temperature and the mean intensity as a function of the redshift. When averaged over a cosmologically large volume, we find that the C II emission from ionized carbon in individual galaxies is larger than the signal generated by carbon in the intergalactic medium. Assuming that the C II luminosity is proportional to the carbon mass in dark matter halos, we also compute the power spectrum of the C II line intensity at various redshifts. In order to avoid the contamination from CO rotational lines at low redshift when targeting a C II survey at high redshifts, we propose the cross-correlation of C II and 21 cm line emission from high redshifts. To explore the detectability of the C II signal from reionization, we also evaluate the expected errors on the C II power spectrum and C II-21 cm cross power spectrum based on the design of the future millimeter surveys. We note that the C II-21 cm cross power spectrum contains interesting features that capture physics during reionization, including the ionized bubble sizes and the mean ionization fraction, which are challenging to measure from 21 cm data alone. We propose an instrumental concept for the reionization C II experiment targeting the frequency range of {approx}200-300 GHz with 1, 3, and 10 m apertures and a bolometric spectrometer array with 64 independent spectral pixels with about 20,000 bolometers.

  15. Line-of-sight geometrical and instrumental resolution effects on intensity perturbations by sausage modes

    NASA Astrophysics Data System (ADS)

    Antolin, P.; Van Doorsselaere, T.

    2013-07-01

    Context. Diagnostics of magnetohydrodynamic (MHD) waves in the solar atmosphere is a topic that often encounters interpretation problems, partly because of the high complexity of the solar atmospheric medium. Forward modelling can significantly guide interpretation, bridging the gap between numerical simulations and observations, and increasing the reliability of mode identification for applying MHD seismology. Aims: We determine the characteristics of the fast MHD sausage mode in the corona on the modulation of observable quantities, such as line intensity and spectral line broadening. Effects of the line-of-sight angle and of spatial, temporal, and spectral resolutions are considered. Methods: We take a cylindrical tube that simulates a loop in a low-β coronal environment with an optically thin background and let it oscillate with the fast sausage mode. A parametric study is performed. Results: Longitudinal structuring of the intensity modulation is obtained and set by the nodal structure of the radial velocity. The modulation is strongly dependent on the contribution function of the spectral line. Under the assumption of equilibrium ionisation, the intensity variation can be very low (≲4% for Fe ix 171) or significant (35% for Fe xii 193). Most of this variation disappears when considering the radiative relaxation times of the ions, due to the fast timescales of the sausage mode in the corona. Regardless of the ionisation state of the plasma, the variation in spectral line broadening can be significant, even for low intensity modulation. The nature of this broadening is not thermal but is mostly turbulent. This places spectrometers in clear advantage over imaging instruments for the detection of the sausage mode. The modulation of all quantities can considerably decrease with the line-of-sight angle with respect to the perpendicular to the tube axis. The spatial and temporal resolution are the main factors affecting modulation, erasing longitudinal

  16. Missing and forbidden links in mutualistic networks

    PubMed Central

    Olesen, Jens M.; Bascompte, Jordi; Dupont, Yoko L.; Elberling, Heidi; Rasmussen, Claus; Jordano, Pedro

    2011-01-01

    Ecological networks are complexes of interacting species, but not all potential links among species are realized. Unobserved links are either missing or forbidden. Missing links exist, but require more sampling or alternative ways of detection to be verified. Forbidden links remain unobservable, irrespective of sampling effort. They are caused by linkage constraints. We studied one Arctic pollination network and two Mediterranean seed-dispersal networks. In the first, for example, we recorded flower-visit links for one full season, arranged data in an interaction matrix and got a connectance C of 15 per cent. Interaction accumulation curves documented our sampling of interactions through observation of visits to be robust. Then, we included data on pollen from the body surface of flower visitors as an additional link ‘currency’. This resulted in 98 new links, missing from the visitation data. Thus, the combined visit–pollen matrix got an increased C of 20 per cent. For the three networks, C ranged from 20 to 52 per cent, and thus the percentage of unobserved links (100 − C) was 48 to 80 per cent; these were assumed forbidden because of linkage constraints and not missing because of under-sampling. Phenological uncoupling (i.e. non-overlapping phenophases between interacting mutualists) is one kind of constraint, and it explained 22 to 28 per cent of all possible, but unobserved links. Increasing phenophase overlap between species increased link probability, but extensive overlaps were required to achieve a high probability. Other kinds of constraint, such as size mismatch and accessibility limitations, are briefly addressed. PMID:20843845

  17. Light Dark Matter from Forbidden Channels.

    PubMed

    D'Agnolo, Raffaele Tito; Ruderman, Joshua T

    2015-08-07

    Dark matter (DM) may be a thermal relic that annihilates into heavier states in the early universe. This forbidden DM framework accommodates a wide range of DM masses from keV to weak scales. An exponential hierarchy between the DM mass and the weak scale follows from the exponential suppression of the thermally averaged cross section. Stringent constraints from the cosmic microwave background are evaded because annihilations turn off at late times. We provide an example where DM annihilates into dark photons, which is testable through large DM self-interactions and direct detection.

  18. Forbidden Fruit and the Prediction of Cigarette Smoking

    PubMed Central

    SUSSMAN, STEVE; GRANA, RACHEL; POKHREL, PALLAV; ROHRBACH, LOUISE A.; SUN, PING

    2011-01-01

    The concept of “forbidden fruit” has been popularly associated with adolescent cigarette smoking in the US. However, only a few empirical studies have been conducted to investigate how this construct operates among adolescents. We examined the concurrent and prospective relationships between two related concepts of forbidden fruit and adolescent cigarette smoking behavior and intention. We found some support for forbidden fruit attitudes as concurrent and longitudinal predictors of smoking and intention to smoke. Implications of these findings are discussed. PMID:20590380

  19. Measuring Galaxy Clustering and the Evolution of [C II] Mean Intensity with Far-IR Line Intensity Mapping during 0.5 < z < 1.5

    NASA Astrophysics Data System (ADS)

    Uzgil, Bade; Aguirre, James E.; Bradford, Charles; Lidz, Adam

    2016-01-01

    Infrared fine-structure emission lines from trace metals are powerful diagnostics of the interstellar medium in galaxies. We explore the possibility of studying the redshifted far-IR fine-structure line emission using the three-dimensional (3D) power spectra obtained with an imaging spectrometer. The intensity mapping approach measures the spatio-spectral fluctuations due to line emission from all galaxies, including those below the individual detection threshold. The technique provides 3D measurements of galaxy clustering and moments of the galaxy luminosity function. Furthermore, the linear portion of the power spectrum can be used to measure the total line emission intensity including all sources through cosmic time with redshift information naturally encoded. As a case study, we consider measurement of [C II] autocorrelation in the 0.5 < z < 1.5 epoch, where interloper lines are minimized, using far-IR/submillimeter balloon-borne and future space-borne instruments with moderate and high sensitivity, respectively. In this context, we compare the intensity mapping approach to blind galaxy surveys based on individual detections. We find that intensity mapping is nearly always the best way to obtain the total line emission because blind, wide-field galaxy surveys lack sufficient depth and deep pencil beams do not observe enough galaxies in the requisite luminosity and redshift bins. Also, intensity mapping is often the most efficient way to measure the power spectrum shape, depending on the details of the luminosity function and the telescope aperture.

  20. Highly accurate intensity factors of pure CO2 lines near 2 μm.

    PubMed

    Odintsova, T A; Fasci, E; Moretti, L; Zak, E J; Polyansky, O L; Tennyson, J; Gianfrani, L; Castrillo, A

    2017-06-28

    Line intensities for carbon dioxide are measured with a novel spectroscopic approach, assisted by an optical frequency comb synthesizer for frequency calibration purposes. The main feature of the spectrometer consists in the exploitation of optical feedback from a V-shaped high-finesse optical resonator to effectively narrow a distributed feedback diode laser at the wavelength of 2 μm. Laser-gas interaction takes place inside an isothermal cell, which is placed on the transmission from the cavity. High quality, self-calibrated, absorption spectra are observed in pure CO2 samples at different gas pressures, in coincidence with three lines of the R-branch of the ν1 + 2ν2 + ν3 band. Line intensities are determined using a global fitting approach in which a manifold of spectra are simultaneously analyzed across the range of pressures between 5 and 100 Torr, sharing a restricted number of unknown parameters. Various sources of uncertainty have been identified and carefully quantified, thus leading to an overall uncertainty ranging between 0.17% and 0.23%. The measured values are in a very good agreement with recent ab initio predictions.

  1. Data-Model Comparisons of Photoelectron Flux Intensities on the Strong Crustal Field Lines at Mars

    NASA Astrophysics Data System (ADS)

    Liemohn, Michael; Trantham, Matthew; Mitchell, David

    2010-05-01

    This study quantifies the factors controlling photoelectron fluxes on strong crustal field lines in the Martian ionosphere. Using data from Mars Global Surveyor's Magnetometer and Electron Reflectometer instruments, dayside electron populations near the strong crustal fields in the southern hemisphere are analyzed versus various controlling parameters. These parameters include a Mars F10.7 proxy, a solar wind pressure proxy, local solar zenith angle, magnetic elevation angle, magnetic field strength. It was found that solar EUV radiation (corrected for solar zenith angle and the Mars-Sun distance) has the strongest influence on the photoelectron fluxes, and during different time periods this radiation has a stronger influence than at others times. Second, fluxes show a slight enhancement when the magnetic elevation angle is near zero degrees (horizontal field lines). Finally, other parameters, such as pressure and magnetic field strength, seem to have no major influence. These measurement-based results are then compared against numerical modeling flux intensities to quantify the physical mechanisms behind the observed relationships. The numerical code used for this study is our superthermal electron transport model, which solves for the electric distribution function along a magnetic field line. The code includes the influence of a variable magnetic field strength, pitch angle scattering and mirror trapping, and collisional energy cascading. The influence of solar EUV flux, atmospheric composition, solar wind dynamic pressure, and the local magnetic field are systematically investigated with this code to understand why some of these parameters have a strong influence on photoelectron flux intensity while others do not.

  2. Highly accurate intensity factors of pure CO2 lines near 2 μ m

    NASA Astrophysics Data System (ADS)

    Odintsova, T. A.; Fasci, E.; Moretti, L.; Zak, E. J.; Polyansky, O. L.; Tennyson, J.; Gianfrani, L.; Castrillo, A.

    2017-06-01

    Line intensities for carbon dioxide are measured with a novel spectroscopic approach, assisted by an optical frequency comb synthesizer for frequency calibration purposes. The main feature of the spectrometer consists in the exploitation of optical feedback from a V-shaped high-finesse optical resonator to effectively narrow a distributed feedback diode laser at the wavelength of 2 μ m. Laser-gas interaction takes place inside an isothermal cell, which is placed on the transmission from the cavity. High quality, self-calibrated, absorption spectra are observed in pure CO2 samples at different gas pressures, in coincidence with three lines of the R-branch of the ν1 + 2ν2 + ν3 band. Line intensities are determined using a global fitting approach in which a manifold of spectra are simultaneously analyzed across the range of pressures between 5 and 100 Torr, sharing a restricted number of unknown parameters. Various sources of uncertainty have been identified and carefully quantified, thus leading to an overall uncertainty ranging between 0.17% and 0.23%. The measured values are in a very good agreement with recent ab initio predictions.

  3. [Multidimensional Strategy Regarding the Reduction of Central-Line Associated Infection in Pediatric Intensive Care].

    PubMed

    Rodrigues, Jorge; Dias, Andrea; Oliveira, Guiomar; Farela Neves, José

    2016-06-01

    To determine the central-line associated bloodstream infection rate after implementation of central venous catheter-care practice bundles and guidelines and to compare it with the previous central-line associated bloodstream infection rate. A prospective, longitudinal, observational descriptive study with an exploratory component was performed in a Pediatric Intensive Care Unit during five months. The universe was composed of every child admitted to Pediatric Intensive Care Unit who inserted a central venous catheter. A comparative study with historical controls was performed to evaluate the result of the intervention (group 1 versus group 2). Seventy five children were included, with a median age of 23 months: 22 (29.3%) newborns; 28 (37.3%) with recent surgery and 32 (43.8%) with underlying illness. A total of 105 central venous catheter were inserted, the majority a single central venous catheter (69.3%), with a mean duration of 6.8 ± 6.7 days. The most common type of central venous catheter was the short-term, non-tunneled central venous catheter (45.7%), while the subclavian and brachial flexure veins were the most frequent insertion sites (both 25.7%). There were no cases of central-line associated bloodstream infection reported during this study. Comparing with historical controls (group 1), both groups were similar regarding age, gender, department of origin and place of central venous catheter insertion. In the current study (group 2), the median length of stay was higher, while the mean duration of central venous catheter (excluding peripherally inserted central line) was similar in both groups. There were no statistical differences regarding central venous catheter caliber and number of lumens. Fewer children admitted to Pediatric Intensive Care Unit had central venous catheter inserted in group 2, with no significant difference between single or multiple central venous catheter. After multidimensional strategy implementation there was no reported

  4. ``Forbidden'' phonon in the iron chalcogenide series

    NASA Astrophysics Data System (ADS)

    Fobes, David M.; Zaliznyak, Igor A.; Xu, Zhijun; Gu, Genda; Tranquada, John M.

    2015-03-01

    Recently, we uncovered evidence for the formation of a bond-order wave (BOW) leading to ferro-orbital order at low temperature, acting to stabilize the bicollinear AFM order, in the iron-rich parent compound, Fe1+yTe. Investigating the inelastic spectra centered near (100) in Fe1+yTe, a signature peak for the BOW formation in the monoclinic phase, we observed an acoustic phonon dispersion in both tetragonal and monoclinic phases. While a structural Bragg peak accompanies the mode in the monoclinic phase, in the tetragonal phase Bragg scattering at this Q is forbidden by symmetry, and we observed no elastic peak. This phonon mode was also observed in superconducting FeTe0.6Se0.4, where structural and magnetic transitions are suppressed. LDA frozen phonon calculations suggested that this mode could result from a spin imbalance between neighboring Fe atoms, but polarized neutron measurements revealed no additional magnetic scattering. We propose that this ``forbidden'' phonon mode may originate from dynamically broken symmetry, perhaps related to the strong dynamic spin correlations in these materials. Work at BNL was supported by BES, US DOE, under Contract No. DE-AC02-98CH10886. Research at ORNL's HFIR and SNS sponsored by Scientific User Facilities Division, BES, US DOE. We acknowledge the support of NIST, in providing neutron research facilities.

  5. Measuring galaxy clustering and the evolution of [C II] mean intensity with far-IR line intensity mapping during 0.5 < z < 1.5

    SciTech Connect

    Uzgil, B. D.; Aguirre, J. E.; Lidz, A.; Bradford, C. M.

    2014-10-01

    Infrared fine-structure emission lines from trace metals are powerful diagnostics of the interstellar medium in galaxies. We explore the possibility of studying the redshifted far-IR fine-structure line emission using the three-dimensional (3D) power spectra obtained with an imaging spectrometer. The intensity mapping approach measures the spatio-spectral fluctuations due to line emission from all galaxies, including those below the individual detection threshold. The technique provides 3D measurements of galaxy clustering and moments of the galaxy luminosity function. Furthermore, the linear portion of the power spectrum can be used to measure the total line emission intensity including all sources through cosmic time with redshift information naturally encoded. Total line emission, when compared to the total star formation activity and/or other line intensities, reveals evolution of the interstellar conditions of galaxies in aggregate. As a case study, we consider measurement of [C II] autocorrelation in the 0.5 < z < 1.5 epoch, where interloper lines are minimized, using far-IR/submillimeter balloon-borne and future space-borne instruments with moderate and high sensitivity, respectively. In this context, we compare the intensity mapping approach to blind galaxy surveys based on individual detections. We find that intensity mapping is nearly always the best way to obtain the total line emission because blind, wide-field galaxy surveys lack sufficient depth and deep pencil beams do not observe enough galaxies in the requisite luminosity and redshift bins. Also, intensity mapping is often the most efficient way to measure the power spectrum shape, depending on the details of the luminosity function and the telescope aperture.

  6. Excitation of the symmetry forbidden bending mode in molecular photoionization

    NASA Astrophysics Data System (ADS)

    Miller, J. Scott; Poliakoff, E. D.; Miller, Thomas F.; Natalense, Alexandra P. P.; Lucchese, Robert R.

    2001-03-01

    We present results on the energy dependence of the vibrational branching ratio for the bending mode in CO2 3σu-1 photoionization. Specifically, we determine the v+=(0,1,0)/v+=(0,0,0) intensity ratio by detecting dispersed fluorescence from the electronically excited photoions. The results exhibit large deviations over a very wide energy range, 18forbidden by symmetry, and while observations of such features are well established in photoelectron spectroscopy, their appearance is normally ascribed to vibronic coupling in the ionic hole state. In this case, we find that such explanations fail to account for the energy dependence of the branching ratio. These deviations indicate that the continuum photoelectron participates in transferring oscillator strength to the nominally forbidden vibrational transition. A theoretical framework is developed for interpreting the experimental data, and Schwinger variational calculations are performed. These calculations demonstrate that the continuum electron is responsible for the observation of the excited bending mode as well as its energy dependence. This is an intrachannel effect that is best described as photoelectron-induced vibronic symmetry breaking. This appears to be a general phenomenon, and it may be useful in illuminating connections between bond angle and photoionization spectroscopies. The magnitude of these deviations display the utility of vibrationally resolved studies, and the extent over which these changes occur underscores the necessity of broad range studies to elucidate slowly varying characteristics in photoionization continua.

  7. Measurement of the Relative Intensity of the Ly-(alpha) Lines in Fe 25+

    SciTech Connect

    Wong, K L; Beiersdorfer, P; Reed, K J; Osterheld, A L

    2002-06-18

    The intensity of the polarized Ly-{alpha}{sub 1} (2p{sub 3/2} {yields} 1s{sub 1/2}) transition has been measured relative to that of the unpolarized Ly-{alpha}{sub 2} (2p{sub 1/2} {yields} 1s{sub 1/2}) transition in Fe{sup 25+}. The measurements were made with the Livermore electron beam ion trap EBIT-II for beam energies from threshold to 2.5 times threshold. The results are compared to the corresponding intensity ratio predicted using excitation cross sections from distorted-wave calculations, which includes polarization, the M1(2s{sub 1/2} {yields} 1s{sub 1/2}) transition, and cascade contributions. Discrepancies are found that tend to confirm a recent report of a measurement of the Ly-{alpha} lines in Ti{sup 21+} performed on the Tokyo electron beam ion trap.

  8. Accurate Intensity Velocity Phase Difference in the Potassium Resonance Line Obtained with VAMOS

    NASA Astrophysics Data System (ADS)

    Magrì, M.; Oliviero, M.; Severino, G.

    2008-01-01

    We present new results about the phase difference between the intensity and velocity fluctuations of the solar photosphere obtained with the Velocity And Magnetic Observations of the Sun (VAMOS) instrument, which uses the magneto-optical filter (MOF) technique. Before this observing run, we applied the calibration method described in Magrì, Oliviero, and Severino ( Solar Phys. 232, 159, 2005) to reduce the instrumental cross-talk which was present in previous VAMOS data. The quality of this calibration, which can be easily applied to any MOF-based instrument, has been confirmed by comparing with the MOF transmission-profile measurements obtained with a diode laser system. Finally, we discuss the new VAMOS phase-difference value in relation to data obtained by other authors in the same potassium spectral line and in other lines that can be used to study nonadiabatic effects of solar global oscillations.

  9. Remote interrogation of WDM fiber-optic intensity sensors deploying delay lines in the virtual domain.

    PubMed

    Montero, David Sánchez; Vázquez, Carmen

    2013-05-07

    In this work a radio-frequency self-referencing WDM intensity-based fiber-optic sensor operating in reflective configuration and using virtual instrumentation is presented. The use of virtual delay lines at the reception stage, along with novel flexible self-referencing techniques, and using a single frequency, avoids all-optical or electrical-based delay lines approaches. This solution preserves the self-referencing and performance characteristics of the proposed WDM-based optical sensing topology, and leads to a more compact solution with higher flexibility for the multiple interrogation of remote sensing points in a sensor network. Results are presented for a displacement sensor demonstrating the concept feasibility.

  10. Low intensity noise and narrow line-width diode laser light at 540 nm

    NASA Astrophysics Data System (ADS)

    Wang, Lirong; Tamaki, Ryo; Kasai, Katsuyuki; Okada-Shudo, Yoshiko; Watanabe, Masayoshi; Zhang, Yun

    2015-05-01

    We present a convenient method to generate high quality single-frequency green light at a wavelength of 540 nm. It consists of a noise suppressed external cavity diode laser at a wavelength of 1080 nm by optical filtering and resonant optical feedback, and a frequency doubling of the fundamental light with an a-cut KTP crystal. Highly efficient conversion is realized by type II non-critical phase matching. A stable single-frequency operation with a maximum power of about 20 mW is performed for more than 3 h. Both the intensity noise and line-width reach the level of a monolithic nonplanar ring laser, which is well known for its extraordinarily narrow line-width and extremely low noise among available single-frequency operating lasers.

  11. Forbidden Zones for Numerically-Controlled Machine Tools

    NASA Technical Reports Server (NTRS)

    Philpot, D.

    1986-01-01

    Computer-controlled machine tool prevented from striking and damaging protruding members on workpiece by creating forbidden zone in control program. With aid of computer graphics, tool profile and coordinates of forbidden zone digitized and stored in computer memory as part of tool path.

  12. Forbidden Zones for Numerically-Controlled Machine Tools

    NASA Technical Reports Server (NTRS)

    Philpot, D.

    1986-01-01

    Computer-controlled machine tool prevented from striking and damaging protruding members on workpiece by creating forbidden zone in control program. With aid of computer graphics, tool profile and coordinates of forbidden zone digitized and stored in computer memory as part of tool path.

  13. Absolute line intensities for carbonyl sulfide from 827 to 2939 cm -1

    NASA Astrophysics Data System (ADS)

    Vander Auwera, J.; Fayt, A.

    2006-01-01

    Using a total of 18 unapodized high-resolution (MOPD=300 and 450 cm) Fourier transform absorption spectra of carbonyl sulfide ( P× ℓ=14.3-60,600 Pa×cm, T=296.0 K), we measured 1340 absolute line intensities in 8 bands (ν+ν21-ν21,2ν20,2ν,ν+2ν20,4ν20,ν,ν21+ν-ν21,ν+ν) of the main isotopologue, located between 827 and 2939 cm -1. In addition, we measured 307 absolute line intensities in the ν 3 fundamental band of 16O 12C 34S and 16O 13C 32S, observed near 2061.45 and 2009.23 cm -1, respectively. The observed Herman-Wallis dependences are in most cases reproduced by the global model of OCS [E. Rbaihi, A. Belafhal, J. Vander Auwera, S. Naïm, and A. Fayt, J. Mol. Spectrosc., 191:32-44, 1998]. The pressure self-broadening parameter was also measured up to J=83.

  14. line profiles for a sample of supergiant HII regions. II. Broad, low intensity components

    NASA Astrophysics Data System (ADS)

    Rozas, M.; Richer, M. G.; López, J. A.; Relaño, M.; Beckman, J. E.

    2006-08-01

    We analyze the broad, low intensity, high velocity components that are seen in the Hα line profiles for a sample of HII regions. These HII regions are chosen from among the brightest and most isolated in a sample of spiral galaxies for which we have photometric and spectroscopic data: NGC 157, NGC 3631, NGC 6764, NGC 3344, NGC 4321, NGC 5364, NGC 5055, NGC 5985, and NGC 7479. We confirm that the line profiles of most of these bright, giant extragalactic HII regions contain broad kinematic components of low intensity, but high velocity, that we denote as wings. We analyze these components, deriving emission measures, central velocities, and velocity dispersions of the blue and red features, which are similar. We interpret these components as expanding shells within the HII regions and produced by the stellar winds from the ionizing stars. We compare the kinetic energies of these expanding shells with the kinetic energy available from the stellar winds. If we allow for the hypothesis that the brightest HII regions are density bounded, we show that, for these HII regions, the stellar wind mechanism can explain the observed shell kinetic energies.

  15. Intensity of Hydrogen Line Emission from Accreting Gas-Giant Planets

    NASA Astrophysics Data System (ADS)

    Aoyama, Yuhiko; Tanigawa, Takayuki; Ikoma, Masahiro

    2015-12-01

    Planets have been thought to form in circumstellar gaseous disks. Indeed, a number of young stars surrounded by such disks have been already detected. Recently, there are some reports on detection of gap-like structure in circumstellar disks, which suggests that there are forming massive protoplanets embedded in the disks. A challenging issue is how to find forming planets in circumstellar disks directly. In this study, we investigate whether detectable emission occurs from accreting gas-giant planets. In a circumstellar disk, once a solid core becomes massive enough, it captures the surrounding disk gas gravitationally in a runaway manner. Since the disk gas accretion occurs much faster than angular momentum loss, a circumplanetary disk is formed in the mid-plane of the circumstellar disk. Recent three-dimensional hydrodynamic simulations by Tanigawa et al. (2012) revealed that the gas flowed from the cicumstellar disk to the circumplanetary disk not horizontally but vertically. According to those simulations, the disk gas falls onto the circumplanetary disk at a speed comparable to the free fall speed, and the local gas temperature reaches up to tens of thousands of kelvin because of shock heating near the planet. Thus, the presence of an accreting gas giant planet may be found by observation of the radiative emission from such hot gas in the circumplanetary disk, which we quantify in this study. In particular, we focus on the intensity of line emission from hydrogen. We have simulated the post-shock gas flow with non-equilibrium chemical reaction and electron transition. Then, we have found that the intensity of some hydrogen lines is proportional to the number density of the surrounding circumstellar disk gas and square of the planet mass, so the protoplanet’s hydrogen-line emission is less intense by a few orders of magnitude relative to the protostar’s emission under some realistic conditions. Also, the duration time is comparable to the dissipation time

  16. Forbidden friends as forbidden fruit: parental supervision of friendships, contact with deviant peers, and adolescent delinquency.

    PubMed

    Keijsers, Loes; Branje, Susan; Hawk, Skyler T; Schwartz, Seth J; Frijns, Tom; Koot, Hans M; van Lier, Pol; Meeus, Wim

    2012-01-01

    Spending leisure time with deviant peers may have strong influences on adolescents' delinquency. The current 3-wave multi-informant study examined how parental control and parental prohibition of friendships relate to these undesirable peer influences. To this end, annual questionnaires were administered to 497 Dutch youths (283 boys, mean age = 13 years at baseline), their best friends, and both parents. Cross-lagged panel analyses revealed strong longitudinal links from contacts with deviant peers to adolescent delinquency, but not vice versa. Parent-reported prohibition of friendships positively predicted contacts with deviant peers and indirectly predicted higher adolescent delinquency. Similar indirect effects were not found for parental control. The results suggest that forbidden friends may become "forbidden fruit," leading to unintended increases in adolescents' own delinquency. © 2011 The Authors. Child Development © 2011 Society for Research in Child Development, Inc.

  17. Line Intensities of Isotopic Carbonyl Sulfide (ocs) at 2.5 Micrometer

    NASA Astrophysics Data System (ADS)

    Toth, Robert A.; Sung, Keeyoon; Brown, Linda R.; Crawford, Timothy J.

    2009-06-01

    We have measured line intensities of ^{16}O^{12}C^{32}S, ^{16}O^{13}C^{32}S, ^{16}O^{12}C^{33}S, ^{16}O^{12}C^{34}S, and ^{18}O^{12}C^{32}S in the 2.5 μm region for the first time to support planetary studies of the Venus atmosphere. Laboratory absorption spectra of OCS were recorded at 0.0033 cm^{-1} resolution at room temperature using a Bruker IFS 125-HR Fourier transform spectrometer at the Jet Propulsion Laboratory. Normal samples of OCS were used in this study, and sample impurities and isotopic abundances were determined from mass spectrum analysis. Optical densities sufficient to observe isotopic bands and weaker hot bands were achieved by using a multi-pass White cell and single pass gas cells in various path lengths, which were validated by analyzing near-IR CO_2 spectra. We present line intensities for almost 30 bands of the OCS isotopes excluding ground state bands of ^{16}O^{12}C^{32}S, which we have reported recently. We have Herman-Wallis factors determined for the individual bands. In some cases, it has been observed that band intensities normalized to 100% isotopic species show a significant deviation from that of the primary isotopic species (up to by 12.5%). No earlier measurements have been reported for these bands. Measurement precision and accuracies will be discussed. Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration. We thank Drs. Stojan Madzunkov, John A. MacAskill, and Murray R. Darrach from the Atomic and Molecular Collision Group at Jet Propulsion Laboratory for recording mass spectrum of the OCS sample used in this work.

  18. Genome size and metabolic intensity in tetrapods: a tale of two lines.

    PubMed

    Vinogradov, Alexander E; Anatskaya, Olga V

    2006-01-07

    We show the negative link between genome size and metabolic intensity in tetrapods, using the heart index (relative heart mass) as a unified indicator of metabolic intensity in poikilothermal and homeothermal animals. We found two separate regression lines of heart index on genome size for reptiles-birds and amphibians-mammals (the slope of regression is steeper in reptiles-birds). We also show a negative correlation between GC content and nucleosome formation potential in vertebrate DNA, and, consistent with this relationship, a positive correlation between genome GC content and nuclear size (independent of genome size). It is known that there are two separate regression lines of genome GC content on genome size for reptiles-birds and amphibians-mammals: reptiles-birds have the relatively higher GC content (for their genome sizes) compared to amphibians-mammals. Our results suggest uniting all these data into one concept. The slope of negative regression between GC content and nucleosome formation potential is steeper in exons than in non-coding DNA (where nucleosome formation potential is generally higher), which indicates a special role of non-coding DNA for orderly chromatin organization. The chromatin condensation and nuclear size are supposed to be key parameters that accommodate the effects of both genome size and GC content and connect them with metabolic intensity. Our data suggest that the reptilian-birds clade evolved special relationships among these parameters, whereas mammals preserved the amphibian-like relationships. Surprisingly, mammals, although acquiring a more complex general organization, seem to retain certain genome-related properties that are similar to amphibians. At the same time, the slope of regression between nucleosome formation potential and GC content is steeper in poikilothermal than in homeothermal genomes, which suggests that mammals and birds acquired certain common features of genomic organization.

  19. Limitations to Accuracy in Extracting Characteristic Line Intensities From X-Ray Spectra

    PubMed Central

    Statham, Peter J.

    2002-01-01

    The early development of quantitative electron probe microanalysis, first using crystal spectrometers, then energy dispersive x-ray spectrometers (EDXS), demonstrated that elements could be detected at 0.001 mass fraction level and major concentrations measured within 2 % relative uncertainty. However, during this period of extensive investigation and evaluation, EDXS detectors were not able to detect x rays below 1 keV and all quantitative analysis was performed using a set of reference standards measured on the instrument. Now that EDXS systems are often used without standards and are increasingly being used to analyse elements using lines well below 1 keV, accuracy can be considerably worse than is documented in standard textbooks. Spectrum processing techniques found most applicable to EDXS have now been integrated into total system solutions and can give excellent results on selected samples. However, the same techniques fail in some applications because of a variety of instrumental effects. Prediction of peak shape, width and position for every characteristic line and measurement of background intensity is complicated by variations in response from system to system and with changing count rate. However, with an understanding of the fundamental sources of error, even a total system can be tested like a “black box” in areas where it is most likely to fail and thus establish the degree of confidence that should apply in the intended application. This approach is particularly important when the microanalysis technique is applied at lower electron beam voltages where the extraction of line intensities is complicated by extreme peak overlap and higher background levels. PMID:27446751

  20. Predicting the intensity mapping signal for multi-J CO lines

    SciTech Connect

    Mashian, Natalie; Loeb, Abraham; Sternberg, Amiel E-mail: amiel@wise.tau.ac.il

    2015-11-01

    We present a novel approach to estimating the intensity mapping signal of any CO rotational line emitted during the Epoch of Reionization (EoR). Our approach is based on large velocity gradient (LVG) modeling, a radiative transfer modeling technique that generates the full CO spectral line energy distribution (SLED) for a specified gas kinetic temperature, volume density, velocity gradient, molecular abundance, and column density. These parameters, which drive the physics of CO transitions and ultimately dictate the shape and amplitude of the CO SLED, can be linked to the global properties of the host galaxy, mainly the star formation rate (SFR) and the SFR surface density. By further employing an empirically derived SFR−M relation for high redshift galaxies, we can express the LVG parameters, and thus the specific intensity of any CO rotational transition, as functions of the host halo mass M and redshift z. Integrating over the range of halo masses expected to host CO-luminous galaxies, we predict a mean CO(1-0) brightness temperature ranging from ∼ 0.6 μK at z = 6 to ∼ 0.03 μK at z = 10 with brightness temperature fluctuations of Δ{sub CO}{sup 2} ∼ 0.1 and 0.005 μK respectively, at k = 0.1 Mpc{sup −1}. In this model, the CO emission signal remains strong for higher rotational levels at z = 6, with ( T{sub CO} ) ∼ 0.3 and 0.05 μK for the CO J = 6arrow5 and CO J = 10arrow9 transitions respectively. Including the effects of CO photodissociation in these molecular clouds, especially at low metallicities, results in the overall reduction in the amplitude of the CO signal, with the low- and high-J lines weakening by 2–20% and 10–45%, respectively, over the redshift range 4 < z < 10.

  1. 158 micron forbidden C II mapping of NGC 6946 - Probing the atomic medium

    NASA Technical Reports Server (NTRS)

    Madden, S. C.; Geis, N.; Genzel, R.; Herrmann, F.; Jackson, J.; Poglitsch, A.; Stacey, G. J.; Townes, C. H.

    1993-01-01

    A well-sampled map (23 x 17 kpc) of the strong 158 micron forbidden C II cooling line in the Scd galaxy NGC 6946 at 55 arcsec resolution is presented which was taken with the MPE/UCB Far-infrared Imaging Fabry-Perot Interferometer (FIFI) in the Kuiper Airborne Observatory. It is concluded that the line emission in NGC 6946 is present in three spatially distinct components including nucleus, spiral arms, and extended region. An extended emission region is a source of most of the forbidden C II luminosity in NGC 6946. The 1 arcmin nuclear component has a line luminosity of 1.5 x 10 exp 7 solar luminosity and contributes 0.15 percent of the galaxy's total FIR luminosity. An extended component of forbidden C II emission is found to exist past the molecular extent of the galaxy and to be present to at least the full dimensions of the map. This component is attributed to a mixture of neutral and atomic clouds.

  2. Introducing an on-line adaptive procedure for prostate image guided intensity modulate proton therapy.

    PubMed

    Zhang, M; Westerly, D C; Mackie, T R

    2011-08-07

    With on-line image guidance (IG), prostate shifts relative to the bony anatomy can be corrected by realigning the patient with respect to the treatment fields. In image guided intensity modulated proton therapy (IG-IMPT), because the proton range is more sensitive to the material it travels through, the realignment may introduce large dose variations. This effect is studied in this work and an on-line adaptive procedure is proposed to restore the planned dose to the target. A 2D anthropomorphic phantom was constructed from a real prostate patient's CT image. Two-field laterally opposing spot 3D-modulation and 24-field full arc distal edge tracking (DET) plans were generated with a prescription of 70 Gy to the planning target volume. For the simulated delivery, we considered two types of procedures: the non-adaptive procedure and the on-line adaptive procedure. In the non-adaptive procedure, only patient realignment to match the prostate location in the planning CT was performed. In the on-line adaptive procedure, on top of the patient realignment, the kinetic energy for each individual proton pencil beam was re-determined from the on-line CT image acquired after the realignment and subsequently used for delivery. Dose distributions were re-calculated for individual fractions for different plans and different delivery procedures. The results show, without adaptive, that both the 3D-modulation and the DET plans experienced delivered dose degradation by having large cold or hot spots in the prostate. The DET plan had worse dose degradation than the 3D-modulation plan. The adaptive procedure effectively restored the planned dose distribution in the DET plan, with delivered prostate D(98%), D(50%) and D(2%) values less than 1% from the prescription. In the 3D-modulation plan, in certain cases the adaptive procedure was not effective to reduce the delivered dose degradation and yield similar results as the non-adaptive procedure. In conclusion, based on this 2D phantom

  3. A comparison of theoretical and solar-flare intensity ratios for the Fe XIX X-ray lines

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Fawcett, B. C.; Phillips, K. J. H.; Lemen, J. R.; Mason, H. E.

    1989-01-01

    Atomic data including energy levels, gf-values, and wavelengths are given for the Fe XIX transitions that give rise to lines in solar-flare and active-region X-ray spectra. Collision strengths and theoretical intensity ratios are presented for lines which occur in the 13.2-14.3-A range. Observed spectra are found to be consistent with those derived from the present Fe XIX atomic data. For the case of spectra in which the Fe XIX lines are very strong, such as those at the maxima of hot flares, two observed line features due to Fe XIX are shown to have larger intensities than calculated. The calculated Fe XIX and Ne IX line spectra are used to determine electron densities from Ne IX line ratios.

  4. Hydrogen Balmer alpha intensity distributions and line profiles from multiple scattering theory using realistic geocoronal models

    NASA Technical Reports Server (NTRS)

    Anderson, D. E., Jr.; Meier, R. R.; Hodges, R. R., Jr.; Tinsley, B. A.

    1987-01-01

    The H Balmer alpha nightglow is investigated by using Monte Carlo models of asymmetric geocoronal atomic hydrogen distributions as input to a radiative transfer model of solar Lyman-beta radiation in the thermosphere and atmosphere. It is shown that it is essential to include multiple scattering of Lyman-beta radiation in the interpretation of Balmer alpha airglow data. Observations of diurnal variation in the Balmer alpha airglow showing slightly greater intensities in the morning relative to evening are consistent with theory. No evidence is found for anything other than a single sinusoidal diurnal variation of exobase density. Dramatic changes in effective temperature derived from the observed Balmer alpha line profiles are expected on the basis of changing illumination conditions in the thermosphere and exosphere as different regions of the sky are scanned.

  5. Hydrogen Balmer alpha intensity distributions and line profiles from multiple scattering theory using realistic geocoronal models

    NASA Technical Reports Server (NTRS)

    Anderson, D. E., Jr.; Meier, R. R.; Hodges, R. R., Jr.; Tinsley, B. A.

    1987-01-01

    The H Balmer alpha nightglow is investigated by using Monte Carlo models of asymmetric geocoronal atomic hydrogen distributions as input to a radiative transfer model of solar Lyman-beta radiation in the thermosphere and atmosphere. It is shown that it is essential to include multiple scattering of Lyman-beta radiation in the interpretation of Balmer alpha airglow data. Observations of diurnal variation in the Balmer alpha airglow showing slightly greater intensities in the morning relative to evening are consistent with theory. No evidence is found for anything other than a single sinusoidal diurnal variation of exobase density. Dramatic changes in effective temperature derived from the observed Balmer alpha line profiles are expected on the basis of changing illumination conditions in the thermosphere and exosphere as different regions of the sky are scanned.

  6. Line intensities and collisional-broadening parameters for the nu4 and nu6 bands of carbonyl fluoride

    NASA Technical Reports Server (NTRS)

    May, Randy D.

    1992-01-01

    Line intensities, air- and self-broadening parameters have been measured for selected lines in the nu4 (1243/cm) and nu6 (774/cm) bands of carbonyl fluoride at 296 and 215 K using a tunable diode-laser spectrometer. Measured line intensities are in good agreement +/- 6 percent with recently reported values derived from rotational analyses of the nu4 and nu6 bands. The measured average air-broadening coefficient at 296 K also agrees well (+/- 5 percent) with N2-broadening coefficients determined from microwave studies, while the average self-broadening coefficient reported here is smaller than a previously reported value by 45 percent.

  7. Diagnostics of recombining laser plasma parameters based on He-like ion resonance lines intensity ratios

    NASA Astrophysics Data System (ADS)

    Ryazantsev, S. N.; Skobelev, I. Yu; Faenov, A. Ya; Pikuz, T. A.; Grum-Grzhimailo, A. N.; Pikuz, S. A.

    2016-11-01

    While the plasma created by powerful laser expands from the target surface it becomes overcooled, i.e. recombining one. Improving of diagnostic methods applicable for such plasma is rather important problem in laboratory astrophysics nowadays because laser produced jets are fully scalable to young stellar objects. Such scaling is possible because of the plasma hydrodynamic equations invariance under some transformations. In this paper it is shown that relative intensities of the resonance transitions in He-like ions can be used to measure the parameters of recombining plasma. Intensity of the spectral lines corresponding to these transitions is sensitive to the density in the range of 1016-1020 cm-3 while the temperature ranges from 10 to 100 eV for ions with nuclear charge Zn ∼ 10. Calculations were carried out for F VIII ion and allowed to determine parameters of plasma jets created by nanosecond laser system ELFIE (Ecole Polytechnique, France) for astrophysical phenomenon modelling. Obtained dependencies are quite universal and can be used for any recombining plasma containing He-like fluorine ions.

  8. Transport of intense ion beams and space charge compensation issues in low energy beam lines (invited).

    PubMed

    Chauvin, N; Delferrière, O; Duperrier, R; Gobin, R; Nghiem, P A P; Uriot, D

    2012-02-01

    Over the last few years, the interest of the international scientific community for high power accelerators in the megawatt range has been increasing. For such machines, the ion source has to deliver a beam intensity that ranges from several tens up to a hundred of mA. One of the major challenges is to extract and transport the beam while minimizing the emittance growth and optimizing its injection into the radio frequency quadrupole. Consequently, it is crucial to perform precise simulations and cautious design of the low energy beam transport (LEBT) line. In particular, the beam dynamics calculations have to take into account not only the space charge effects but also the space charge compensation of the beam induced by ionization of the residual gas. The physical phenomena occurring in a high intensity LEBT and their possible effects on the beam are presented, with a particular emphasis on space charge compensation. Then, beam transport issues in different kind of LEBTs are briefly reviewed. The SOLMAXP particle-in-cell code dedicated to the modeling of the transport of charge particles under a space charge compensation regime is described. Finally, beam dynamics simulations results obtained with SOLMAXP are presented in the case of international fusion materials irradiation facility injector.

  9. Magnetic circular dichroism of symmetry and spin forbidden transitions of high-spin metal ions

    NASA Astrophysics Data System (ADS)

    Oganesyan, Vasily S.; Thomson, Andrew J.

    2000-09-01

    Recently we have developed a general method of analyzing magnetic circular dichroism (MCD) spectra and magnetization curves of high-spin metal ions for spin-allowed transitions [Oganesyan et al., J. Chem. Phys. 110, 762 (1999)]. In the present article this approach is extended to cover the cases of spin- and symmetry-forbidden transitions. At high ligand fields many low-energy ligand field transitions become spin-forbidden. Extraction of information content about the electronic structure of the ground state can be obtained through the analysis and correlation of the positions, signs, and intensities of the MCD bands and magnetization curves of these transitions. The casting of the theory in terms of the irreducible tensor method allows full advantage to be taken of any symmetry elements and simplifies multielectron calculations. The theory is valid over the entire range of magnetic field strength and, therefore, allows the information content of spectra over the full field and temperature range to be exploited. The method is applied to the analysis of the recorded MCD spectra and magnetization curves of the lowest energy spin-forbidden ligand field transitions of pseudo-tetrahedral high-spin Fe(III), S=5/2, in the protein rubredoxin from Methanobacterium thermoautotrophicum (strain Marburg). The predicted signs, intensities, and magnetization curves for these transitions are in excellent agreement with experimental data. We also show that when the anisotropy of the ground state is larger than the Zeeman splitting the MCD of both spin-forbidden and allowed transitions can become comparable in magnitude. Hence caution is needed in order to avoid the misinterpretation of experimental results.

  10. Intense gamma-ray lines from hidden vector dark matter decay

    SciTech Connect

    Arina, Chiara; Hambye, Thomas; Ibarra, Alejandro; Weniger, Christoph E-mail: thambye@ulb.ac.be E-mail: christoph.weniger@desy.de

    2010-03-01

    Scenarios with hidden, spontaneously broken, non-abelian gauge groups contain a natural dark matter candidate, the hidden vector, whose longevity is due to an accidental custodial symmetry in the renormalizable Lagrangian. Nevertheless, non-renormalizable dimension six operators break the custodial symmetry and induce the decay of the dark matter particle at cosmological times. We discuss in this paper the cosmic ray signatures of this scenario and we show that the decay of hidden vector dark matter particles generically produce an intense gamma ray line which could be observed by the Fermi-LAT experiment, if the scale of custodial symmetry breaking is close to the Grand Unification scale. This gamma line proceeds directly from a tree level dark matter 2-body decay in association with a Higgs boson. Within this model we also perform a determination of the relic density constraints taking into account the dark matter annihilation processes with one dark matter particle in the final state. The corresponding direct detection rates can be easily of order the current experimental sensitivities.

  11. Management of arterial lines and blood sampling in intensive care: a threat to patient safety.

    PubMed

    Leslie, R A; Gouldson, S; Habib, N; Harris, N; Murray, H; Wells, V; Cook, T M

    2013-11-01

    In 2008, the UK National Patient Safety Agency (NPSA) made recommendations for safe arterial line management. Following a patient safety incident in our intensive care unit (ICU), we surveyed current practice in arterial line management and determined whether these recommendations had been adopted. We contacted all 241 adult ICUs in the UK; 228 (94.6%) completed the survey. Some NPSA recommendations have been widely implemented - use of sodium chloride 0.9% as flush fluid, two-person checking of fluids before use - and their practice was consistent. Others have been incompletely implemented and many areas of practice (prescription of fluids, two-person checking at shift changes, use of opaque pressure bags, arterial sampling technique) were highly variable. More importantly, the use of the wrong fluid as an arterial flush was reported by 30% of respondents for ICU practice, and a further 30% for practice elsewhere in the hospital. Our survey provides evidence of continuing risk to patients. © 2013 The Association of Anaesthetists of Great Britain and Ireland.

  12. Far-infrared line intensities of H2O and CO from warm molecular clouds

    NASA Technical Reports Server (NTRS)

    Takahashi, T.; Hollenbach, D. J.; Silk, J.

    1985-01-01

    Takahashi et al. (1983) have studied the role of H2O in the overall energetics of warm molecular clouds with large optical depths. It was found that in molecular clouds associated with nearby or embedded luminosity sources, the dust is likely to be warmer than the molecular gas. Thus, the warm dust represents the primary source of heat for the gas. In some cases, H2O was found to cool the gas. Takahashi et al. (1983) have presented the formalism for treating H2O in an optically thick molecular cloud with embedded sources of luminosity. The total H2O heating and cooling rates were also calculated. In the present investigation, the emergent intensities of far-infrared lines of H2O and excited, rotational CO transitions from relatively warm molecular clouds based on the large-velocity gradient model of the previous study are calculated. It is found that the dominant submillimeter CO transitions are related to emission, while the H2O transitions can be either absorption or emission lines.

  13. Forbidden phenotypes and the limits of evolution

    PubMed Central

    Vermeij, Geerat J.

    2015-01-01

    Evolution has produced an astonishing array of organisms, but does it have limits and, if so, how are these overcome and how have they changed over the course of time? Here, I review models for describing and explaining existing diversity, and then explore parts of the evolutionary tree that remain empty. In an analysis of 32 forbidden states among eukaryotes, identified in major clades and in the three great habitat realms of water, land and air, I argue that no phenotypic constraint is absolute, that most constraints reflect a limited time–energy budget available to individual organisms, that natural selection is ultimately responsible for both imposing and overcoming constraints, including those normally ascribed to developmental patterns of construction and phylogenetic conservatism, and that increases in adaptive versatility in major clades together with accompanying new ecological opportunities have eliminated many constraints. Phenotypes that were inaccessible during the Early Palaeozoic era have evolved during later periods while very few adaptive states have disappeared. The filling of phenotypic space has proceeded cumulatively in three overlapping phases characterized by diversification at the biochemical, morphological and cultural levels. PMID:26640643

  14. Quantitative extraction of spectral line intensities and widths from x-ray spectra recorded with gated microchannel plate detectors.

    PubMed

    Dunham, Greg; Bailey, J E; Rochau, G A; Lake, P W; Nielsen-Weber, L B

    2007-06-01

    Plasma spectroscopy requires determination of spectral line intensities and widths. At Sandia National Laboratories Z facility we use elliptical crystal spectrometers equipped with gated microchannel plate detectors to record time and space resolved spectra. We collect a large volume of data typically consisting of five to six snapshots in time and five to ten spectral lines with 30 spatial elements per frame, totaling to more than 900 measurements per experiment. This large volume of data requires efficiency in processing. We have addressed this challenge by using a line fitting routine to automatically fit each spectrum using assumed line profiles and taking into account photoelectron statistics to efficiently extract line intensities and widths with uncertainties. We verified that the random data noise obeys Poisson statistics. Rescale factors for converting film exposure to effective counts required for understanding the photoelectron statistics are presented. An example of the application of these results to the analysis of spectra recorded in Z experiments is presented.

  15. Numerical and experimental study of atomic transport and Balmer line intensity in Linac4 negative ion source

    SciTech Connect

    Shibata, T. Nishida, K.; Hatayama, A.; Mattei, S.; Lettry, J.

    2015-04-08

    Time structure of Balmer H{sub α} line intensity in Linac4 RF plasma has been analyzed by the combined simulation model of atomic transport and Collisional-Radiative models. As a preliminary result, time variation of the line intensity in the ignition phase of RF plasma is calculated and compared with the experimental results by photometry. For the comparison, spatial distribution of the local H{sub α} photon emission rate at each time is calculated from the numerical model. The contribution of the local photon emission rates to the observed line intensity via optical viewing port is also investigated by application of the mock-up of the optical viewing port and the known light source. It has been clarified from the analyses that the higher and the lower peaks of the H{sub α} line intensity observed during 1 RF cycle is mainly due to the different spatial distributions in the electron energy distribution function and the resultant local photon emission rate. These results support previous suggestion that the existence of the capacitive electric field in axial direction leads to the higher/lower peaks of the line intensity.

  16. Comparing the H-alpha Intensity and Radio Wave Scattering on Eight Low-Latitude Lines of Sight

    NASA Astrophysics Data System (ADS)

    Simonetti, J. H.; Dennison, B.; Topasna, G. A.

    1995-12-01

    Spangler and Reynolds compared H-alpha intensities, measured using the Wisconsin Fabry-Perot interferometer, with radio-wave scattering sizes of eight extragalactic sources along low-latitiude lines of sight. They find that some correlation exists between scattering and H-alpha intensity, as one might expect. However, the H-alpha observations were made with a 50(') beam size; higher resolution observations might provide a more accurate measure of the intensity along the scattering line of sight. We made sensitive, arcminute resolution H-alpha images of the same fields to upgrade the accuracy of their results. We find that many of their measured H-alpha intensities are accurate, but some of the higher intensities are biased upward by the presence of clumped emission. Appropriate reduction of these large intensities increases the degree of correlation between scattering and H-alpha intensity, thus strengthening their original conclusions. This work is a first step towards using our spectral-line imaging system for a more extensive study of the relationship between the warm ionized medium and scattering of radio waves. This research was supported by NSF grant AST-9319670 and a grant from the Horton Foundation to Virginia Tech.

  17. The filamentary nebula YM 29 - Spectrograms and emission-line photographs

    NASA Astrophysics Data System (ADS)

    Lozinskaya, T. A.; Sitnik, T. G.; Toropova, M. S.

    1986-04-01

    Spectrograms as well as monochromatic photographs and isophotes in three emission features have been obtained for YM 29, an old planetary nebula of Peimbert type PN I. The morphology depends on the ionization state: diffuse forbidden O III emission is accompanied by fine forbidden N II, forbidden S II filaments. Moreover the radiation is stratified, with regions bright in the forbidden O II line located 10-40 arcsec closer to the nucleus than the forbidden N II, forbidden S II emission sites. Similar morphology distinctions and stratification, typifying nebulae ionized by the central star's ultraviolet radiation, have previously been reported in a kindred object, Simeiz 22.

  18. Automated Measurement of Nerve Fiber Density Using Line Intensity Scan Analysis

    PubMed Central

    Sathyanesan, Aaron; Ogura, Tatsuya; Lin, Weihong

    2012-01-01

    Quantification of nerve fibers in peripheral and central nervous systems is important for the understanding of neuronal function, organization and pathological changes. However, current methods to quantify nerve fibers are resource-intensive and often provide an indirect measurement of nerve fiber density. Here, we describe an automated and efficient method for nerve fiber quantification, which we developed by making use of widely available software and analytical techniques, including Hessian-based feature extraction in NIH ImageJ and line intensity scan analysis. The combined use of these analytical tools through an automated routine enables reliable detection and quantification of nerve fibers from low magnification, non-uniformly labeled epifluorescence images. This allows for time-efficient determination of nerve density and also comparative analysis in large brain structures, such as hippocampus or between various regions of neural circuitry. Using this method, we have obtained accurate measurements of cholinergic fiber density in hippocampus and a large area of cortex in mouse brain sections immunolabeled with an antibody against the vesicular acetylcholine transporter (VAChT). The density values are comparable among animals tested, showing a high degree of reproducibility. Because our method can be performed at relatively low cost and in large tissue sections where nerve fibers can be labeled by various antibodies or visualized by expression of reporter proteins, such as green fluorescent protein in transgenic mice, we expect our method to be broadly useful in both research and clinical investigation. To our knowledge, this is the first method to reliably quantify nerve fibers through a rapid and automated protocol. PMID:22613744

  19. Conversion of "Tables of Spectral-Line Intensities" for NBS copper arc into table for inductively coupled argon plasmas

    NASA Astrophysics Data System (ADS)

    Boumans, P. W. J. M.

    This paper describes an approach used to convert the Tables of Spectral-Line Intensities for the copper arc explored by M EGGERS, C ORLISS and S CRIBNER at the National Bureau of Standards (NBS Tables) into a table appropriate for inductively coupled plasmas (ICP). Previous work of this author was extended to determine "definitive" factors for converting the intensities listed in the NBS Tables into ICP sensitivities using the ICP detection limits of more than 800 prominent lines published by W INGE, P ETERSON and F ASSEL. A computer iteration procedure was devised to find simultaneously the desired conversion factors and the true relative intensity distribution in the background spectrum of the argon ICP explored by W INGE et al. This approach proved to be viable and resulted in a complete translation of the tables for the NBS copper arc into a table of ICP sensitivities, which, together with a previously described approach by this author to quantify line coincidences in terms of critical concentration ratios, formed the basis of new Line Coincidence Tables for Inductively Coupled Plasma Atomic Emission Spectrometry involving 896 prominent lines of 67 elements. The Appendix of the present work produces a list of these prominent lines arranged according to element and wavelength, along with sensitivities, detection limits, and ratios of the detection limits to the best detection limit of the element. A second list of some 200 supplementary computer predicted prominent lines is also appended.

  20. Interstellar CaII line intensities and the distances of the OB stars

    NASA Astrophysics Data System (ADS)

    Krełowski, J.; Galazutdinov, G. A.; Megier, A.; Strobel, A.; Bondar, A.; Musaev, F. A.; Han, I.

    We show that the equivalent widths of the well-known interstellar CaII H and K lines can be used to determine the distances to OB stars in our Galaxy. The equivalent widths, measured in the spectra of 149 early-type stars, exhibit a simple (approximately inverse) relation with Hipparcos parallaxes. It was Struve (1928) who first observed the relation between the "detached" CaII K line and estimated distance. Further work on the subject was published by Sanford (1937), Merrill (1937), Evans (1941), and Beals and Oke (1953). While many later studies have used the CaII (and other atomic) lines to study both spatial and velocity structure of the interstellar medium, the early results on the intensity × distance relation were for nearly half a century difficult to improve on, because of the problems associated with estimating stellar distances in the appropriate distance range (hundreds of parsecs). The publication of the Hipparcos Catalogue (ESA 1997) made available a set of parallaxes for 120 thousand stars measured with miliarcsecond accuracy. Using this homogeneous source of parallax data, and a collection of high resolution spectra of 149 OB stars, we investigate the dependence of the equivalent widths of CaII H and K interstellar lines on parallax. For many stars in our sample, the errors in Hipparcos parallaxes are comparable to the parallaxes themselves. We studied the relations directly in the parallax × equivalent width diagrams, avoiding problems (e.g truncation bias) associated with the inversion (Arenou & Luri 1999, Smith 2003). We have selected for this project a set of 149 early-type stars (no later than B3), where the influence of possible stellar contamination of H and K lines is negligible. The spectra have been collected using echelle spectrographs of several observatories: MAESTRO (Terskol, Northern Caucasus), Feros (ESO) and BOES (Korea). The spectral resolution varies between 30,000 and 120,000. Figure 1 presents the parallax vs EW(CaII H

  1. Discovery of Time Variation of the Intensity of Molecular Lines in IRC+10216 in The Submillimeter and Far Infrared Domains

    PubMed Central

    Cernicharo, J.; Teyssier, D.; Quintana-Lacaci, G.; Daniel, F.; Agúndez, M.; Prieto, L. Velilla; Decin, L.; Guélin, M.; Encrenaz, P.; García-Lario, P.; de Beck, E.; Barlow, M.J.; Groenewegen, M.A.T.; Neufeld, D.; Pearson, J.

    2015-01-01

    We report on the discovery of strong intensity variations in the high rotational lines of abundant molecular species towards the archetypical circumstellar envelope of IRC+10216. The observations have been carried out with the HIFI instrument on board Herschel1 and with the IRAM2 30-m telescope. They cover several observing periods spreading over 3 years. The line intensity variations for molecules produced in the external layers of the envelope most probably result from time variations in the infrared pumping rates. We analyze the main implications this discovery has on the interpretation of molecular line emission in the envelopes of Mira-type stars. Radiative transfer calculations have to take into account both the time variability of infrared pumping and the possible variation of the dust and gas temperatures with stellar phase in order to reproduce the observation of molecular lines at different epochs. The effect of gas temperature variations with stellar phase could be particularly important for lines produced in the innermost regions of the envelope. Each layer of the circumstellar envelope sees the stellar light radiation with a different lag time (phase). Our results show that this effect must be included in the models. The sub-mm and FIR lines of AGB stars cannot anymore be considered as safe intensity calibrators. PMID:26722620

  2. Discovery of Time Variation of the Intensity of Molecular Lines in IRC+10216 in The Submillimeter and Far Infrared Domains.

    PubMed

    Cernicharo, J; Teyssier, D; Quintana-Lacaci, G; Daniel, F; Agúndez, M; Prieto, L Velilla; Decin, L; Guélin, M; Encrenaz, P; García-Lario, P; de Beck, E; Barlow, M J; Groenewegen, M A T; Neufeld, D; Pearson, J

    2014-10-20

    We report on the discovery of strong intensity variations in the high rotational lines of abundant molecular species towards the archetypical circumstellar envelope of IRC+10216. The observations have been carried out with the HIFI instrument on board Herschel and with the IRAM 30-m telescope. They cover several observing periods spreading over 3 years. The line intensity variations for molecules produced in the external layers of the envelope most probably result from time variations in the infrared pumping rates. We analyze the main implications this discovery has on the interpretation of molecular line emission in the envelopes of Mira-type stars. Radiative transfer calculations have to take into account both the time variability of infrared pumping and the possible variation of the dust and gas temperatures with stellar phase in order to reproduce the observation of molecular lines at different epochs. The effect of gas temperature variations with stellar phase could be particularly important for lines produced in the innermost regions of the envelope. Each layer of the circumstellar envelope sees the stellar light radiation with a different lag time (phase). Our results show that this effect must be included in the models. The sub-mm and FIR lines of AGB stars cannot anymore be considered as safe intensity calibrators.

  3. ANALYSIS OF BREIT-PAULI TRANSITION PROBABILITIES FOR LINES IN O III

    SciTech Connect

    Fischer, C. Froese; Tachiev, G.; Rubin, R. H.; Rodriguez, M.

    2009-09-20

    Accurate atomic data are essential for understanding the properties of both O III lines produced by the Bowen fluorescence mechanism and [O III] forbidden lines observed in numerous gaseous nebulae. Improved Breit-Pauli transition probabilities have been published for the carbon sequence. Included were revised data for O III. The present paper analyzes the accuracy of the data specifically for O III by comparison with other theory as well as some recent experiments and observations. For the electric dipole transition probabilities, good agreement is found for allowed Bowen fluorescence lines between predictions of intensity ratios with observed data. For forbidden transitions, the Breit-Pauli magnetic dipole transition operator requires corrections that often are neglected. Good agreement is found when these transition probabilities are computed with multiconfiguration Dirac-Hartree-Fock methods.

  4. The intensities and profiles of XUV transition zone lines in a quiet sun region compared to a polar coronal hole

    NASA Technical Reports Server (NTRS)

    Feldman, U.; Doschek, G. A.; Tousey, R.

    1975-01-01

    The intensities of XUV transition-zone lines from limb spectra of a quiet-sun region and a polar coronal hole are compared. The spectra were obtained with a slit spectrograph on Skylab and cover a region from -12 sec within the limb to 20 sec above it. The lines selected for comparison are formed at temperatures that range from 36,000 to 220,000 K. Lines of the higher-temperature ions, e.g. O v, are significantly less intense in the coronal hole, and lines of lower-temperature ions show little change. Profiles of selected optically thin transition-zone lines from the quiet-sun and coronal-hole spectra are also shown. The lines are broader than expected in ionization equilibrium, and bulk-motion velocities are deduced from the widths of the lines. There appears to be little, if any, statistically significant difference in the velocities obtained from the quiet-sun region and the coronal hole.

  5. Real Distribution of the Coronal Green Line Intensity and Modelling Study of Galactic Cosmic Ray Propagation

    NASA Astrophysics Data System (ADS)

    Gushchina, R. T.; Alania, M. V.; Gil, A.; Iskra, K.; Siluszyk, M.

    2003-07-01

    transport equation of galactic cosmic rays (GCR) has been numerically solved for different qA>0 (1996) and qA<0 (1987) epochs assuming that free path of GCR scattering in the interplanetary space is controlled by the Sun's coronal green line intensity (CGLI). We found some distinctions in the distribution of the expected heliolatitudinal gradients of GCR for two and three dimensional interplanetary magnetic field. INTRODUCTION. modulation of GCR in the interplanetary space is generally determined by four processesdiffusion, convection, drift and energy change of GCR particles due to interaction with the solar wind. The joint effect of all above mentioned processes result the 11year variation of GCR. In papers [1-3] are assumed that the general reason of the 11-year variation of GCR in the energy range more than 1 GeV is different structure of the irregularities of the IMF in the maxima and minima epochs of solar activity (SA) caused the radical changes of the dependence of diffusion coefficient on the rigidity of GCR particles. EXPERIMENTAL DATA AND METHOD OF INVESTIGATION. experimental data of sunspot numbers, sunspots' areas and CGLI (λ = 5303˚) show a considerable changes during the 11-year cycle of SA, while e.g. A the changes of the solar wind velocity are not so noticeable [4, 5]. An attempt to take into account influences of the real distributions of the sunspot's areas and the Sun's CGLI on the modulation of GCR considering delay time of the phenomena in the interplanetary space with respect to the processes on the Sun have been undertaken in papers [6-8]. One of parameters of SA contentiously observed on the Earth is the Sun's CGLI. One can suppose that a modulation of GCR by some means is controlled by the changes of the CGLI; particularly there is assumed that a scattering free path of GCR transport is related with the

  6. Central line-associated bloodstream infections in the intensive care unit: importance of the care bundle

    PubMed Central

    Doğanay, Zahide; Çelik, Hale Kefeli; Tomak, Leman; Günal, Özgür; Kılıç, S. Sırrı

    2016-01-01

    Background The importance and efficacy of a care bundle for preventing central line-associated bloodstream infections (CLABSIs) and infectious complications related to placing a central venous catheter (CVC) in patients in the intensive care unit (ICU). Methods A care bundle was implemented from July 2013 to June 2014 in a medical ICU and surgical ICU. Data were divided into three periods: the prior period (July 2012–June 2013), the intervention period (July 2013–June 2014; first and second periods), and the post-intervention period (July 2014–December 2014; third period). A care bundle consisting of optimal hand hygiene, skin antisepsis with chlorhexidine (2%) allowing the skin to dry, maximal barrier precautions for inserting a catheter (sterile gloves, gown, mask, and drapes), choice of optimal insertion site, prompt catheter removal, and daily evaluation of the need for the CVC was introduced. Results The catheterization duration was longer and femoral access was more frequently observed in patients with CLABSIs. CLABSI rates decreased with use of the care bundle. The CLABSI rate in the medical ICU was 6.20/1,000 catheter days during the prior period, 3.88/1,000 catheter days during the intervention period, and 1.05/1,000 catheter days during the third period. The CLABSI rate in the surgical ICU was 8.27/1,000, 4.60/1,000, and 3.73/1,000 catheter days during these three periods, respectively. Conclusions The choice of an optimal catheter insertion site, use of all barrier precautions, and removal of catheters when they are no longer needed are essential to decrease the CLABSI rate. PMID:27924201

  7. Contribution of inner shell Compton ionization to the X-ray fluorescence line intensity

    NASA Astrophysics Data System (ADS)

    Fernández, Jorge E.; Scot, Viviana; Di Giulio, Eugenio

    2016-10-01

    The Compton effect is a potential ionization mechanism of atoms. It produces vacancies in inner shells that are filled with the same mechanism of atomic relaxation as the one following photo-absorption. This contribution to X-ray fluorescence emission is frequently neglected because the total Compton cross-section is apparently much lower than the photoelectric one at useful X-ray energies. However, a more careful analysis suggests that is necessary to consider single shell cross sections (instead of total cross sections) as a function of energy. In this article these Compton cross sections are computed for the shells K, L1-L3 and M1-M5 in the framework of the impulse approximation. By comparing the Compton and the photoelectric cross-section for each shell it is then possible to determine the extent of the Compton correction to the intensity of the corresponding characteristic lines. It is shown that for the K shell the correction becomes relevant for excitation energies which are too high to be influent in X-ray spectrometry. In contrast, for L and M shells the Compton contribution is relevant for medium-Z elements and medium energies. To illustrate the different grades of relevance of the correction, for each ionized shell, the energies for which the Compton contribution reaches the extent levels of 1, 5, 10, 20, 50 and 100% of the photoelectric one are determined for all the elements with Z = 11-92. For practical applications it is provided a simple formula and fitting coefficients to compute average correction levels for the shells considered.

  8. Dipole forbidden vibrational modes for NO and CO on Cu observed in the far IR

    SciTech Connect

    Hirschmugl, C.J. |; Dumas, P.; Suhren, M.; Chabal, Y.J.; Hoffmann, F.M.; Williams, G.P.

    1993-11-01

    IRRAS spectra of NO/Cu(111) and ({radical}3 {times} {radical}3)R30{degrees} coverage of CO/Cu(111) in the range 3000--180 cm{sup {minus}1} show both the adsorbate internal modes and features assigned to the hindered rotational modes. These dipole-forbidden features are characterized by asymmetric (mostly negative) absorption lineshapes and are accompanied by a change in broadband absorption. The shape and intensity of this broadband absorption is well accounted for by a scattering model.

  9. X-ray line spectral signatures of plasmas driven by high- intensity ultra-short laser pulses

    NASA Astrophysics Data System (ADS)

    Hakel, Peter

    2001-11-01

    In this dissertation we report on our atomic-kinetics and X-ray line spectra modeling work in the context of plasmas generated by high-intensity, ultrashort-duration pulsed lasers. We focus on characterizing the properties of X-ray line emissions (i.e., intensity, broadening, and polarization) as signatures of plasma conditions, discuss the relevant atomic processes, and introduce atomic kinetics as a means for their quantitative assessment. This also requires the knowledge of detailed line shapes including the effects of Doppler and natural broadening, Stark broadening, line shifts and radiation transport. A suite of time-dependent, collisional-radiative atomic kinetics and spectral codes, CRAK/SPECTRUM, were developed. We applied these codes to the analysis of K- shell aluminum X-ray line spectra recorded in experiments using layered targets performed at the Max-Planck- Institut für Quantenoptik. Modeling calculations indicate that red line shifts observed in these experiments cannot be explained by shifts in the centers of gravity of composite spectral features due to enhanced satellite contributions, but are consistent with line shift effects in resonance and satellite lines. We discuss the mechanism of polarized X-ray line emission in plasmas, its connection to plasma anisotropy, and introduce an atomic kinetics model and code (POLAR) based on the population kinetics of magnetic sublevels. POLAR represents a multi-level, multi-process approach to the problem of polarized spectra in plasmas, and hence it is well suited for plasma applications where cascade effects and alignment transfer can become important. Polarization degrees of X-ray spectral lines computed with POLAR were successfully benchmarked against calculations done with other formalisms, and experimental results obtained at the EBIT facility of Lawrence Livermore National Laboratory. We investigate the polarization of He-like Si X-ray satellite lines as spectral signatures of anisotropy in the

  10. Anomalous He-like ion resonance-to-intercombination line intensity ratios in discharge and laser produced plasmas

    NASA Astrophysics Data System (ADS)

    Shlyaptsev, Vyacheslav; Avaria, G.; Li, J.; Tomasel, F. G.; Busquet, M.; Klapish, M.; Faenov, A. Ya.; Rocca, J. J.; Csu Team; Artep Team; Osaka University Team

    2016-10-01

    Highly anomalous resonance-to-intercombination line intensity ratios were observed in He-like ions spectra from plasmas created in high current density microcapillary channels by ultrafast current pulses (<= 4ns risetime). The emission from discharges containing Si or Al impurities show intercombination line intensities to exceed the resonance line intensities by nearly an order of magnitude. The analysis and detailed hydrodynamic/atomic physics model simulations suggest that the effect responsible for the spectral anomaly reported here is different from those observed to cause similar abnormalities in other plasmas, and is related instead to a new phenomenon in which the very different optical depths in the transverse and axial directions generate triplet level populations greatly exceeding the singlet state populations. The modeling suggests that for different experimental conditions there could be even much larger line ratios observed. The model predictions were tested in wide range parameters and methods of plasma creation including laser produced plasma. This work was supported by NSF Physics Award PHY-1004295.

  11. Limits on Lorentz violation from forbidden β decays.

    PubMed

    Noordmans, J P; Wilschut, H W; Timmermans, R G E

    2013-10-25

    Forbidden (slow) β decays offer new opportunities to test the invariance of the weak interaction under Lorentz transformations. Within a general effective field theory framework we analyze and reinterpret the only two relevant experiments, performed in the 1970s, dedicated to search for a preferred direction in space in first- and second-forbidden β decays. We show that the results of these experiments put strong and unique limits on Lorentz violation, and in particular on the presence of several interactions in the modern Lorentz-violating standard model extension. We discuss prospects to improve on these limits.

  12. Forbidden patterns, permutation entropy and stock market inefficiency

    NASA Astrophysics Data System (ADS)

    Zunino, Luciano; Zanin, Massimiliano; Tabak, Benjamin M.; Pérez, Darío G.; Rosso, Osvaldo A.

    2009-07-01

    In this paper we introduce two new quantifiers for the stock market inefficiency: the number of forbidden patterns and the normalized permutation entropy. They are model-independent measures, thus they have more general applicability. We find robust evidence that degree of market inefficiency is positively correlated with the number of forbidden patterns and negatively correlated with the permutation entropy. Our empirical results suggest that these two physical tools are useful to discriminate the stage of stock market development and can be easily implemented.

  13. Comparing Administrative and Clinical Data for Central Line Associated Blood Stream Infections in Pediatric Intensive Care Unit and Pediatric Cardiothoracic Intensive Care Unit

    PubMed Central

    Bond, Jory; Issa, Mohamed; Nasrallah, Ali; Bahroloomi, Sheena; Blackwood, Roland A.

    2016-01-01

    Central line associated bloodstream infections (CLABSIs) are a frequent source of health complication for patients of all ages, including for patients in the pediatric intensive care unit (PICU) and Pediatric Cardiothoracic Intensive Care Unit (PCTU). Many hospitals, including the University of Michigan Health System, currently use the International Classification of Disease (ICD) coding system when coding for CLABSI. The purpose of this study was to determine the accuracy of coding for CLABSI infections with ICD-9CM codes in PICU and PCTU patients. A retrospective chart review was conducted for 75 PICU and PCTU patients with 90 events of hospital acquired central line infections at the University of Michigan Health System (from 2007-2011). The different variables examined in the chart review included the type of central line the patient had, the duration of the stay of the line, the type of organism infecting the patient, and the treatment the patient received. A review was conducted to assess if patients had received the proper ICD-9CM code for their hospital acquired infection. In addition, each patient chart was searched using Electronic Medical Record Search Engine to determine if any phrases that commonly referred to hospital acquired CLABSIs were present in their charts. Our review found that in most CLABSI cases the hospital’s administrative data diagnosis using ICD-9CM coding systems did not code for the CLABSI. Our results indicate a low sensitivity of 32% in the PICU and an even lower sensitivity of 12% in the PCTU. Using these results, we can conclude that the ICD-9CM coding system cannot be used for accurately defining hospital acquired CLABSIs in administrative data. With the new use of the ICD-10CM coding system, further research is needed to assess the effects of the ICD-10CM coding system on the accuracy of administrative data.

  14. Emission-Line Intensity Ratios in Fe XVII Observed with a Microcalorimeter on an Electron Beam Ion Trap

    NASA Astrophysics Data System (ADS)

    Laming, J. M.; Kink, I.; Takacs, E.; Porto, J. V.; Gillaspy, J. D.; Silver, E. H.; Schnopper, H. W.; Bandler, S. R.; Brickhouse, N. S.; Murray, S. S.; Barbera, M.; Bhatia, A. K.; Doschek, G. A.; Madden, N.; Landis, D.; Beeman, J.; Haller, E. E.

    2000-12-01

    We report new observations of emission line intensity ratios of Fe XVII under controlled experimental conditions, using the National Institute of Standards and Technology electron beam ion trap (EBIT) with a microcalorimeter detector. We compare our observations with collisional-radiative models using atomic data computed in distorted wave and R-matrix approximations, which follow the transfer of the polarization of level populations through radiative cascades. Our results for the intensity ratio of the 2p61S0- 2p53d1P1 15.014 Å line to the 2p61S0- 2p53d3D1 15.265 Å line are 2.94+/-0.18 and 2.50+/-0.13 at beam energies of 900 and 1250 eV, respectively. These results are not consistent with collisional-radiative models and support conclusions from earlier EBIT work at the Lawrence Livermore National Laboratory that the degree of resonance scattering in the solar 15.014 Å line has been overestimated in previous analyses. Further observations assess the intensity ratio of the three lines between the 2p6-2p53s configurations to the three lines between the 2p6-2p53d configurations. Both R-matrix and distorted wave approximations agree with each other and our experimental results much better than most solar and stellar observations, suggesting that other processes not present in our experiment must play a role in forming the Fe XVII spectrum in solar and astrophysical plasmas.

  15. Measurement of multiplet intensities and noble gas-broadened line widths in the nu 3 fundamental of methane

    NASA Technical Reports Server (NTRS)

    Varanasi, P.; Pugh, L. A.; Bangaru, B. R. P.

    1974-01-01

    Presented integrated intensity data at 300 K for J multiplets between P(11) and R(11) in the nu-3 fundamental of C-12 methane are shown to be in good agreement with most previously published pertinent values. Also, line widths measured at 100 K, 130 K, 190 K, 250 K, and 300 K for R(0), R(1), and R(2) broadened by He, Ne, and Ar are presented, and the line-width temperature dependence is discussed for the three cases of broadening.

  16. Line positions and intensities for the gamma 1 + gamma 2 and gamma 2 + gamma 3 bands of (16)O3

    NASA Technical Reports Server (NTRS)

    Devi, V. Malathy; Flaud, J.-M.; Canypeyret, C.; Rinsland, C. P.; Smith, M. A. H.

    1988-01-01

    Using 0.005 cm-resolution Fourier transform spectra of (16)O3, generated by electric discharge from a greater than 99.98 percent pure sample of (16)O3, an extensive analysis of the gamma 1 + gamma 2 and the gamma 2 + gamma 3 bands in the 5.7 micron region was performed. The rotational energy levels of the upper (110) and (011) vibrational states of (16)O3 were reproduced within their experimental uncertainties using a Hamiltonian which takes explicitly into account the Coriolis-type interaction occurring between the rotational energy levels of both states. Improved vibrational energies and rotational and coupling constants were also derived for the (110) and (011) states. Precise transition moment constants for these two bands were deduced from analysis of 220 measured line intensities. Finally, a complete list of line positions, intensities, and lower state energies for both bands has been generated.

  17. Use of generalized population ratios to obtain Fe XV line intensities and linewidths at high electron densities

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Bhatia, A. K.

    1980-01-01

    A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284-500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t(ij), related to 'taboo' probabilities of Markov chain theory. The t(ij) are here evaluated for a real atomic system, being therefore of potential interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.

  18. A computer program for fast non-LTE analysis of interstellar line spectra. With diagnostic plots to interpret observed line intensity ratios

    NASA Astrophysics Data System (ADS)

    van der Tak, F. F. S.; Black, J. H.; Schöier, F. L.; Jansen, D. J.; van Dishoeck, E. F.

    2007-06-01

    Aims:The large quantity and high quality of modern radio and infrared line observations require efficient modeling techniques to infer physical and chemical parameters such as temperature, density, and molecular abundances. Methods: We present a computer program to calculate the intensities of atomic and molecular lines produced in a uniform medium, based on statistical equilibrium calculations involving collisional and radiative processes and including radiation from background sources. Optical depth effects are treated with an escape probability method. The program is available on the World Wide Web at http://www.sron.rug.nl/~vdtak/radex/index.shtml. The program makes use of molecular data files maintained in the Leiden Atomic and Molecular Database (LAMDA), which will continue to be improved and expanded. Results: The performance of the program is compared with more approximate and with more sophisticated methods. An Appendix provides diagnostic plots to estimate physical parameters from line intensity ratios of commonly observed molecules. Conclusions: This program should form an important tool in analyzing observations from current and future radio and infrared telescopes. Appendices A-D, are only available in electronic form at http://www.aanda.org

  19. Forbidden coronal iron-like emission in the Puppis A shock front - The effect of inhomogeneities

    NASA Technical Reports Server (NTRS)

    Teske, Richard G.; Petre, Robert

    1987-01-01

    CCD images of the shock front at the eastern rim of Pup A, obtained in the forbidden lines of Fe X (6374 A) and Fe XIV (5303 A), are reported and compared to Einstein high-resolution-image soft X-ray data. The observed part of the remnant is complex, containing density irregularities. Optical and X-ray data are consistent in showing a nearly flat gradient of ionization temperature behind the shock. To determine conditions in the shock, scans of surface brightness across it in the optical lines were compared to surface brightnesses predicted by idealized Sedov models. It was not possible to match both the red and green line scans by a simple, single-component model, and the failure is ascribed to the presence of the density inhomogeneities. This result has important implications for the determination of SNR shock-front models by fitting X-ray data with Sedov models.

  20. Proposed rocket experiments to measure the profile and intensity of the solar He1584A resonance line

    NASA Technical Reports Server (NTRS)

    Judge, D. L.

    1978-01-01

    The intensity and profile of the helium resonance line at 584 A from the entire disc of the sun was investigated using a rocket-borne helium-filled spectrometer and a curve of growth technique. The line profile was found to be accurately represented by a Gaussian profile with full width at half maximum of 122 plus or minus 10m A while the integrated intensity was measured to be (2.6 plus or minus 1.3) x 10 to the 9th power/photons sec sq cm at solar levels of F sub 10.7 = 90.8 x 10 to the minus 22th power/sq m H sub z and R sub z = 27. The measured linewidth is in good agreement with previous spectrographic measurement but the integrated intensity is larger than most previous photoelectric measurements. However, the derived line center flux of (2.0 plus or minus 1.0) x 10 to the 10th power/photons sec sq cm A is in good agreement with values inferred from airglow measurements.

  1. In-line Filtration Decreases Systemic Inflammatory Response Syndrome, Renal and Hematologic Dysfunction in Pediatric Cardiac Intensive Care Patients.

    PubMed

    Sasse, Michael; Dziuba, Friederike; Jack, Thomas; Köditz, Harald; Kaussen, Torsten; Bertram, Harald; Beerbaum, Philipp; Boehne, Martin

    2015-08-01

    Cardiac surgery with cardiopulmonary bypass (CPB) frequently leads to systemic inflammatory response syndrome (SIRS) with concomitant organ malfunction. Infused particles may exacerbate inflammatory syndromes since they activate the coagulation cascade and alter inflammatory response or microvascular perfusion. In a randomized, controlled, prospective trial, we have previously shown that particle-retentive in-line filtration prevented major complications in critically ill children. Now, we investigated the effect of in-line filtration on major complications in the subgroup of cardiac patients. Children admitted to tertiary pediatric intensive care unit were randomized to either control or filter group obtaining in-line filtration throughout complete infusion therapy. Risk differences and 95 % confidence intervals (CI) of several complications such as SIRS, sepsis, mortality, various organ failure and dysfunction were compared between both groups using the Wald method. 305 children (n = 150 control, n = 155 filter group) with cardiac diseases were finally analyzed. The majority was admitted after cardiac surgery with CPB. Risk of SIRS (-11.3 %; 95 % CI -21.8 to -0.5 %), renal (-10.0 %; 95 % CI -17.0 to -3.0 %) and hematologic (-8.1 %; 95 % CI -14.2 to -0.2 %) dysfunction were significantly decreased within the filter group. No risk differences were demonstrated for occurrence of sepsis, any other organ failure or dysfunctions between both groups. Infused particles might aggravate a systemic hypercoagulability and inflammation with subsequent organ malfunction in pediatric cardiac intensive care patients. Particle-retentive in-line filtration might be effective in preventing SIRS and maintaining renal and hematologic function. In-line filtration offers a novel therapeutic option to decrease morbidity in cardiac intensive care.

  2. Generalization of Suppression in Norma Khouri's "Forbidden Love"

    ERIC Educational Resources Information Center

    Mariam, Olya; Rana, Sidra

    2014-01-01

    The aim of this research is to critique the repercussions of over-generalization of a social issue as depicted in Norma Khouri's "Forbidden Love." The novel/memoir has been written against the 9/11 backdrop and as such serves as means of sensationalizing and exploiting a cultural event which unfortunately echoes in the East. The…

  3. Line intensities of methane in the 2700-2862-kayser region

    NASA Technical Reports Server (NTRS)

    Hunt, R. H.; Brown, L. R.; Toth, R. A.

    1978-01-01

    Individual strengths and wave numbers of 2080 methane absorption lines have been measured between 2700 and 2862 kaysers at an average resolution of 0.023 kayser using a grating spectrometer. The results include all lines with strengths greater than 0.00003 per sq cm/atm observable at 296 K with a maximum path of 32 m and a pressure of 4 torr.

  4. Numerical Modelling of Intense Electron Beam Transport in the Spiral Line Induction Accelerator

    DTIC Science & Technology

    1992-08-28

    arising in the context of the spiral line induction accelerator (SLIA), a device in which the beam is transported along an open-ended beam pipe ...field. Because the field coils are wound directly onto the spiral beam pipe , and because each bend is magnetically shielded from its neighbors, each... Spiral Line Induction Accelerator J. KRALL, S. SLINKER, M. LAMPE AND G. JOYCE Beam Physics Branch Plasma Physics Division August 28, 1992 _pw DTIC U)lz E

  5. Line intensities and temperature-dependent line broadening coefficients of Q-branch transitions in the v2 band of ammonia near 10.4 μm

    NASA Astrophysics Data System (ADS)

    Sur, Ritobrata; Spearrin, R. Mitchell; Peng, Wen Y.; Strand, Christopher L.; Jeffries, Jay B.; Enns, Gregory M.; Hanson, Ronald K.

    2016-05-01

    We report measured line intensities and temperature-dependent broadening coefficients of NH3 with Ar, N2, O2, CO2, H2O, and NH3 for nine sQ(J,K) transitions in the ν2 fundamental band in the frequency range 961.5-967.5 cm-1. This spectral region was chosen due to the strong NH3 absorption strength and lack of spectral interference from H2O and CO2 for laser-based sensing applications. Spectroscopic parameters were determined by multi-line fitting using Voigt lineshapes of absorption spectra measured with two quantum cascade lasers in thermodynamically-controlled optical cells. The temperature dependence of broadening was measured over a range of temperatures between 300 and 600 K. These measurements aid the development of mid-infrared NH3 sensors for a broad range of gas mixtures and at elevated temperatures.

  6. Simultaneous analysis of the Ballik-Ramsay and Phillips systems of C2 and observation of forbidden transitions between singlet and triplet states

    NASA Astrophysics Data System (ADS)

    Chen, Wang; Kawaguchi, Kentarou; Bernath, Peter F.; Tang, Jian

    2015-02-01

    6229 lines of the Ballik-Ramsay system (b3Σg--a3Πu) and the Phillips system (A1Πu-X1Σg+) of C2 up to v = 8 and J = 76, which were taken from the literature or assigned in the present work, were analyzed simultaneously by least-squares fitting with 82 Dunham-like molecular parameters and spin-orbit interaction constants between the b3Σg- and X1Σg+ states with a standard deviation of 0.0037 cm-1 for the whole data set. As a result of the deperturbation analysis, the spin-orbit interaction constant AbX was determined as 6.333(7) cm-1 and the energy difference between the X1Σg+ and a3Πu states was determined as 720.008(2) cm-1 for the potential minima or 613.650(3) cm-1 for the v = 0 levels with Merer and Brown's N2 Hamiltonian for 3Π states, which is about 3.3 cm-1 larger than the previously determined value. Due to this sizable change, a new energy-level crossing was found at J = 2 for v = 3 (F1) of b3Σg- state and v = 6 of X1Σg+ state, where the strong interaction causes a nearly complete mixing of the wave functions of the b3Σg- and X1Σg+ states and the forbidden transitions become observable. Using the predictions of our deperturbation analysis, we were able to identify 16 forbidden transitions between the singlet and triplet states at the predicted frequencies with the expected intensities, which verifies our value for the energy difference between the X1Σg+ and a3Πu states.

  7. Simultaneous analysis of the Ballik-Ramsay and Phillips systems of C2 and observation of forbidden transitions between singlet and triplet states.

    PubMed

    Chen, Wang; Kawaguchi, Kentarou; Bernath, Peter F; Tang, Jian

    2015-02-14

    6229 lines of the Ballik-Ramsay system (b(3)Σg (-)-a(3)Πu) and the Phillips system (A(1)Πu-X(1)Σg (+)) of C2 up to v = 8 and J = 76, which were taken from the literature or assigned in the present work, were analyzed simultaneously by least-squares fitting with 82 Dunham-like molecular parameters and spin-orbit interaction constants between the b(3)Σg (-) and X(1)Σg (+) states with a standard deviation of 0.0037 cm(-1) for the whole data set. As a result of the deperturbation analysis, the spin-orbit interaction constant AbX was determined as 6.333(7) cm(-1) and the energy difference between the X(1)Σg (+) and a(3)Πu states was determined as 720.008(2) cm(-1) for the potential minima or 613.650(3) cm(-1) for the v = 0 levels with Merer and Brown's N(2) Hamiltonian for (3)Π states, which is about 3.3 cm(-1) larger than the previously determined value. Due to this sizable change, a new energy-level crossing was found at J = 2 for v = 3 (F1) of b(3)Σg (-) state and v = 6 of X(1)Σg (+) state, where the strong interaction causes a nearly complete mixing of the wave functions of the b(3)Σg (-) and X(1)Σg (+) states and the forbidden transitions become observable. Using the predictions of our deperturbation analysis, we were able to identify 16 forbidden transitions between the singlet and triplet states at the predicted frequencies with the expected intensities, which verifies our value for the energy difference between the X(1)Σg (+) and a(3)Πu states.

  8. Power lines, roads, and avian nest survival: effects on predator identity and predation intensity

    PubMed Central

    DeGregorio, Brett A; Weatherhead, Patrick J; Sperry, Jinelle H

    2014-01-01

    1 Anthropogenic alteration of landscapes can affect avian nest success by influencing the abundance, distribution, and behavior of predators. Understanding avian nest predation risk necessitates understanding how landscapes affect predator distribution and behavior. 2 From a sample of 463 nests of 17 songbird species, we evaluated how landscape features (distance to forest edge, unpaved roads, and power lines) influenced daily nest survival. We also used video cameras to identify nest predators at 137 nest predation events and evaluated how landscape features influenced predator identity. Finally, we determined the abundance and distribution of several of the principal predators using surveys and radiotelemetry. 3 Distance to power lines was the best predictor of predator identity: predation by brown-headed cowbirds (Molothrus ater), corvids (Corvus sp. and Cyanocitta cristata), racers (Coluber constrictor), and coachwhips (Masticophis flagellum) increased with proximity to power lines, whereas predation by rat snakes (Elaphe obsoleta) and raptors decreased. In some cases, predator density may reliably indicate nest predation risk because racers, corvids, and cowbirds frequently used power line right-of-ways. 4 Of five bird species with enough nests to analyze individually, daily nest survival of only indigo buntings (Passerina cyanea) decreased with proximity to power lines, despite predation by most predators at our site being positively associated with power lines. For all nesting species combined, distance to unpaved road was the model that most influenced daily nest survival. This pattern is likely a consequence of rat snakes, the locally dominant nest predator (28% of predation events), rarely using power lines and associated areas. Instead, rat snakes were frequently associated with road edges, indicating that not all edges are functionally similar. 5 Our results suggest that interactions between predators and landscape features are likely to be specific to

  9. Power lines, roads, and avian nest survival: effects on predator identity and predation intensity.

    PubMed

    DeGregorio, Brett A; Weatherhead, Patrick J; Sperry, Jinelle H

    2014-05-01

    1 Anthropogenic alteration of landscapes can affect avian nest success by influencing the abundance, distribution, and behavior of predators. Understanding avian nest predation risk necessitates understanding how landscapes affect predator distribution and behavior. 2 From a sample of 463 nests of 17 songbird species, we evaluated how landscape features (distance to forest edge, unpaved roads, and power lines) influenced daily nest survival. We also used video cameras to identify nest predators at 137 nest predation events and evaluated how landscape features influenced predator identity. Finally, we determined the abundance and distribution of several of the principal predators using surveys and radiotelemetry. 3 Distance to power lines was the best predictor of predator identity: predation by brown-headed cowbirds (Molothrus ater), corvids (Corvus sp. and Cyanocitta cristata), racers (Coluber constrictor), and coachwhips (Masticophis flagellum) increased with proximity to power lines, whereas predation by rat snakes (Elaphe obsoleta) and raptors decreased. In some cases, predator density may reliably indicate nest predation risk because racers, corvids, and cowbirds frequently used power line right-of-ways. 4 Of five bird species with enough nests to analyze individually, daily nest survival of only indigo buntings (Passerina cyanea) decreased with proximity to power lines, despite predation by most predators at our site being positively associated with power lines. For all nesting species combined, distance to unpaved road was the model that most influenced daily nest survival. This pattern is likely a consequence of rat snakes, the locally dominant nest predator (28% of predation events), rarely using power lines and associated areas. Instead, rat snakes were frequently associated with road edges, indicating that not all edges are functionally similar. 5 Our results suggest that interactions between predators and landscape features are likely to be specific to

  10. Formaldehyde Emission in Comet C/2002 T7 (LINEAR) at Infrared Wavelengths: Line-by-Line Validation of Modeled Fluorescent Intensities

    NASA Astrophysics Data System (ADS)

    DiSanti, Michael A.; Bonev, B. P.; Dello Russo, N.; Magee-Sauer, K.; Mumma, M. J.; Reuter, D. C.; Villanueva, G. L.; Anderson, W. M.; Gibb, E. L.

    2006-09-01

    Cometary nuclei are the most primitive remnants of the early Solar System, so measuring abundances of their ices allows a glimpse into the conditions in which icy bodies formed. Only in the last several years has it become possible to routinely study native cometary volatiles at infrared wavelengths. In spring 2004, we observed comet C/2002 T7 (LINEAR, hereafter C/T7) using the CSHELL spectrometer at the NASA-IRTF 3-m telescope. CSHELL offers sufficiently high spectral resolving power (λ/δλ 2.5 x 104) to permit line-by-line intensities to be measured. Emission lines from multiple molecular species were targeted in the 2.9 - 5.0 micron spectral region, and our observations revealed an extremely rich chemistry in C/T7, including formaldehyde (H2CO). H2CO is ubiquitous in dense interstellar clouds, so its presence is expected in comets if they contain interstellar material. These bodies delivered enormous quantities of pre-biotic chemicals to the young Earth, thus the abundance of H2CO in comets is of keen astrobiological interest. C/T7 provided the best opportunity to date to compare H2CO line intensities predicted by an existing fluorescence model1 with high-resolution comet spectra. We present results2 showing a high degree of correlation between model and data. This work validates the model and permits highly reliable measures of rotational temperature and production rate of H2CO, for comparison with chemically related molecules (CO, methyl alcohol) in C/T7 and other comets in our database. This research was supported by the NASA Planetary Atmospheres (RTOP 344-33-55), Astrobiology (RTOP 344-53-51), and Planetary Astronomy (RTOP 344-32-98) Programs. References: 1Reuter, D. C., et al. 1989 Ap J 341:1045-1058; 2DiSanti, M. A., et al. 2006 Ap J (in press)

  11. Line positions and intensities of the phosphine (PH3) Pentad near 4.5 μm

    NASA Astrophysics Data System (ADS)

    Malathy Devi, V.; Kleiner, Isabelle; Sams, Robert L.; Brown, Linda R.; Benner, D. Chris; Fletcher, Leigh N.

    2014-04-01

    In order to improve the spectroscopic database for remote sensing of the giant planets, line positions and intensities are determined for the five bands (2ν2, ν2 + ν4, 2ν4, ν1 and ν3) that comprise the Pentad of PH3 between 1950 and 2450 cm-1. Knowledge of PH3 spectral line parameters in this region is important for the exploration of dynamics and chemistry on Saturn, (using existing Cassini/VIMS observations) and future near-IR data of Jupiter from Juno and ESA's Jupiter Icy Moons Explorer (JUICE). For this study, spectra of pure PH3 from two Fourier transform spectrometers were obtained: (a) five high-resolution (0.00223 cm-1), high signal-to-noise (∼1800) spectra recorded at room temperature (298.2 K) with the Bruker IFS 125HR Fourier transform spectrometer (FTS) at the Pacific Northwest National Laboratory (PNNL), Richland, Washington and (b) four high-resolution (at 0.0115 cm-1 resolution), high signal-to-noise (∼700) spectra recorded at room temperature in the region 1800-5200 cm-1 using the McMath-Pierce Fourier transform spectrometer located at the National Solar Observatory (NSO) on Kitt Peak. Individual line parameters above 2150 cm-1 were retrieved by simultaneous multispectrum fittings of all five Bruker spectra, while retrievals with the four Kitt Peak spectra were done in the 1938-2168 cm-1 range spectrum by spectrum and averaged. In all, positions and intensities were obtained for more than 4400 lines. These included 53 A+A- split pairs of transitions (arising due to vibration-rotation interactions (Coriolis-type interaction) between the ν3 and ν1 fundamental bands) for K″ = 3, 6, and 9. Over 3400 positions and 1750 intensities of these lines were ultimately identified as relatively unblended and modeled up to J = 14 and K = 12 with rms values of 0.00133 cm-1 and 7.7%, respectively. The PH3 line parameters (observed positions and measured intensities with known quantum assignments) and Hamiltonian constants are reported. Comparisons

  12. Line positions and intensities of the phosphine (PH3) Pentad near 4.5μm

    SciTech Connect

    Malathy Devi, V.; Kleiner, Isabelle; Sams, Robert L.; Brown, Linda R.; Benner, D. Chris; Fletcher, Leigh N.

    2014-04-01

    In order to improve the spectroscopic database for remote sensing of the giant planets, line positions and intensities are determined for the five bands (2ν2, ν2 + ν4, 2ν4, ν1 and ν3) that comprise the Pentad of PH3 between 1950 and 2450 cm-1. Knowledge of PH3 spectral line parameters in this region is important for the exploration of dynamics and chemistry on Saturn, (using existing Cassini/VIMS observations) and future near-IR data of Jupiter from Juno and ESA’s Jupiter Icy Moons Explorer (JUICE). For this study, spectra of pure PH3 from two Fourier transform spectrometers were obtained: (a) five high-resolution (0.00223 cm-1), high signal-to-noise (~1800) spectra recorded at room temperature (298.2 K) with the Bruker IFS 125HR Fourier transform spectrometer (FTS) at the Pacific Northwest National Laboratory (PNNL), Richland, Washington and (b) four high-resolution (at 0.0115 cm-1 resolution), high signal-to-noise (~700) spectra recorded at room temperature in the region 1800–5200 cm-1 using the McMath-Pierce Fourier transform spectrometer located at the National Solar Observatory (NSO) on Kitt Peak. Individual line parameters above 2150 cm-1 were retrieved by simultaneous multispectrum fittings of all five Bruker spectra, while retrievals with the four Kitt Peak spectra were done in the 1938–2168 cm-1 range spectrum by spectrum and averaged. In all, positions and intensities were obtained for more than 4400 lines. These included 53 A+A- split pairs of transitions (arising due to vibration–rotation interactions (Coriolis-type interaction) between the ν3 and ν1 fundamental bands) for K" = 3, 6, and 9. Over 3400 positions and 1750 intensities of these lines were ultimately identified as relatively unblended and modeled up to J = 14 and K = 12 with rms values of 0

  13. Atomic data from the Iron Project. LIII. Relativistic allowed and forbidden transition probabilities for Fe XVII

    NASA Astrophysics Data System (ADS)

    Nahar, Sultana N.; Eissner, Werner; Chen, Guo-Xin; Pradhan, Anil K.

    2003-09-01

    An extensive set of fine structure levels and corresponding transition probabilities for allowed and forbidden transitions in Fe XVII is presented. A total of 490 bound energy levels of Fe XVII of total angular momenta 0 <= J <= 7 of even and odd parities with 2 <= n<= 10, 0 <= l<= 8, 0 <= L<= 8, and singlet and triplet multiplicities, are obtained. They translate to over 2.6x 104 allowed (E1) transitions that are of dipole and intercombination type, and 2312 forbidden transitions that include electric quadrupole (E2), magnetic dipole (M1), electric octopole (E3), and magnetic quadrupole (M2) type representing the most detailed calculations to date for the ion. Oscillator strengths f, line strengths S, and coefficients A of spontaneous emission for the E1 type transitions are obtained in the relativistic Breit-Pauli R-matrix approximation. A-values for the forbidden transitions are obtained from atomic structure calculations using codes SUPERSTRUCTURE and GRASP. The energy levels are identified in spectroscopic notation with the help of a newly developed level identification algorithm. Nearly all 52 spectroscopically observed levels have been identified, their binding energies agreeing within 1% with our calculation. Computed transition probabilities are compared with other calculations and measurement. The effect of 2-body magnetic terms and other interactions is discussed. The present data set enhances by more than an order of magnitude the heretofore available data for transition probabilities of Fe XVII. Complete electronic data tables of energies and transition probabilities are only 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?J/A+A/408/789

  14. Recombination line intensities for hydrogenic ions. III - Effects of finite optical depth and dust

    NASA Technical Reports Server (NTRS)

    Hummer, D. G.; Storey, P. J.

    1992-01-01

    The effect on the recombination spectrum of hydrogen arising from: (1) finite optical thickness in the Lyman lines; (2) the overlapping of Lyman lines near the series limit; (3) the absorption of Lyman lines by dust or photoionization, and (4) the long-wave radiation emitted by dust is examined. Full account is taken of electron and heavy particle collisions in redistributing energy and angular momentum. It is seen that each of these deviations from the classical Case B leads to observable effects, and that dust influences the recombination spectrum in characteristic ways that may make possible new observational constraints on dust properties in nebulosities. On the basis of these calculations it is believed that the uncertainty in the determination of the helium-to-hydrogen abundance ratio in the universe may be larger than currently claimed.

  15. Aspirin is first-line treatment for migraine and episodic tension-type headache regardless of headache intensity.

    PubMed

    Lampl, Christian; Voelker, Michael; Steiner, Timothy J

    2012-01-01

    (1) To establish whether pre-treatment headache intensity in migraine or episodic tension-type headache (ETTH) predicts success or failure of treatment with aspirin; and (2) to reflect, accordingly, on the place of aspirin in the management of these disorders. Stepped care in migraine management uses symptomatic treatments as first-line, reserving triptans for those in whom this proves ineffective. Stratified care chooses between symptomatic therapy and triptans as first-line on an individual basis according to perceived illness severity. We questioned the 2 assumptions underpinning stratified care in migraine that greater illness severity: (1) reflects greater need; and (2) is a risk factor for failure of symptomatic treatment but not of triptans. With regard to the first assumption, we developed a rhetorical argument that need for treatment is underpinned by expectation of benefit, not by illness severity. To address the second, we reviewed individual patient data from 6 clinical trials of aspirin 1000 mg in migraine (N = 2079; 1165 moderate headache, 914 severe) and one of aspirin 500 and 1000 mg in ETTH (N = 325; 180 moderate, 145 severe), relating outcome to pre-treatment headache intensity. In migraine, for headache relief at 2 hours, a small (4.7%) and non-significant risk difference (RD) in therapeutic gain favored moderate pain; for pain freedom at 2 hours, therapeutic gains were almost identical (RD: -0.2%). In ETTH, for headache relief at 2 hours, RDs for both aspirin 500 mg (-4.2%) and aspirin 1000 mg (-9.7%) favored severe pain, although neither significantly; for pain freedom at 2 hours, RDs (-14.2 and -3.6) again favored severe pain. In neither migraine nor ETTH does pre-treatment headache intensity predict success or failure of aspirin. This is not an arguable basis for stratified care in migraine. In both disorders, aspirin is first-line treatment regardless of headache intensity. © 2011 American Headache Society.

  16. Minimising central line-associated bloodstream infection rate in inserting central venous catheters in the adult intensive care units.

    PubMed

    Hina, Hedaya Rateb; McDowell, Joan R S

    2017-03-23

    To investigate the procedural aspects in inserting central venous catheters that minimise central line-associated bloodstream infection rates in adult intensive care units through a structured literature review. In adult intensive care units, central line-associated bloodstream infections are a major cause of high mortality rates and increased in costs due to the consequences of complications. Eligible articles were identified by combining indexed keywords using Boolean operator of "AND" under databases of Ovid and CINAHL. Titles and abstract of retrieved papers were screened and duplicates removed. Inclusion and exclusion criteria were applied to derive the final papers, which contained seminal studies. The quality of papers was assessed using a special data extraction form. The number of papers retrieved from all databases was 337, reduced to 302 after removing duplicates. Papers were scanned for titles and abstract to locate those relevant to the review question. After this, 250 papers were excluded for different reasons and a total of 52 papers were fully accessed to assess for eligibility. The final number of papers included was 10 articles. Many interventions can be implemented in the adult intensive care unit during the insertion of a central venous catheter to minimise central line-associated bloodstream infections rates. These include choosing the subclavian site to insert the catheters as the least infectious and decolonising patients' skin with alcoholic chlorhexidine gluconate preparation due to its broad antimicrobial effect and durability. Choosing optimal sites for central venous catheter insertion is a complex process that relies on many factors. Furthermore, the introduction of chlorhexidine gluconate preparations should be accompanied with multifaceted interventions including quality improvement initiatives to improve healthcare workers' compliance. As a quality marker in adult intensive care units, healthcare sectors should work on establishing

  17. Recovery of acetylene absorption line profile basing on tunable diode laser spectroscopy with intensity modulation and photoacoustic spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Li; Thursby, Graham; Stewart, George; Arsad, Norhana; Uttamchandani, Deepak; Culshaw, Brian; Wang, Yiding

    2010-04-01

    A novel and direct absorption line recovery technique based on tunable diode laser spectroscopy with intensity modulation is presented. Photoacoustic spectroscopy is applied for high sensitivity, zero background and efficient acoustic enhancement at a low modulation frequency. A micro-electromechanical systems (MEMS) mirror driven by an electrothermal actuator is used for generating laser intensity modulation (without wavelength modulation) through the external reflection. The MEMS mirror with 10μm thick structure material layer and 100nm thick gold coating is formed as a circular mirror of 2mm diameter attached to an electrothermal actuator and is fabricated on a chip that is wire-bonded and placed on a PCB holder. Low modulation frequency is adopted (since the resonant frequencies of the photoacoustic gas cell and the electrothermal actuator are different) and intrinsic high signal amplitude characteristics in low frequency region achieved from measured frequency responses for the MEMS mirror and the gas cell. Based on the property of photoacoustic spectroscopy and Beer's law that detectable sensitivity is a function of input laser intensity in the case of constant gas concentration and laser path length, a Keopsys erbium doped fibre amplifier (EDFA) with opto-communication C band and high output power up to 1W is chosen to increase the laser power. High modulation depth is achieved through adjusting the MEMS mirror's reflection position and driving voltage. In order to scan through the target gas absorption line, the temperature swept method is adopted for the tunable distributed feed-back (DFB) diode laser working at 1535nm that accesses the near-infrared vibration-rotation spectrum of acetylene. The profile of acetylene P17 absorption line at 1535.39nm is recovered ideally for ~100 parts-per-million (ppm) acetylene balanced by nitrogen. The experimental signal to noise ratio (SNR) of absorption line recovery for 500mW laser power was ~80 and hence the

  18. CONTINUUM INTENSITY AND [O i] SPECTRAL LINE PROFILES IN SOLAR 3D PHOTOSPHERIC MODELS: THE EFFECT OF MAGNETIC FIELDS

    SciTech Connect

    Fabbian, D.; Moreno-Insertis, F. E-mail: fmi@iac.es

    2015-04-01

    The importance of magnetic fields in three-dimensional (3D) magnetoconvection models of the Sun’s photosphere is investigated in terms of their influence on the continuum intensity at different viewing inclination angles and on the intensity profile of two [O i] spectral lines. We use the RH numerical radiative transfer code to perform a posteriori spectral synthesis on the same time series of magnetoconvection models used in our publications on the effect of magnetic fields on abundance determination. We obtain a good match of the synthetic disk-center continuum intensity to the absolute continuum values from the Fourier Transform Spectrometer (FTS) observational spectrum; the match of the center-to-limb variation synthetic data to observations is also good, thanks, in part, to the 3D radiation transfer capabilities of the RH code. The different levels of magnetic flux in the numerical time series do not modify the quality of the match. Concerning the targeted [O i] spectral lines, we find, instead, that magnetic fields lead to nonnegligible changes in the synthetic spectrum, with larger average magnetic flux causing both of the lines to become noticeably weaker. The photospheric oxygen abundance that one would derive if instead using nonmagnetic numerical models would thus be lower by a few to several centidex. The inclusion of magnetic fields is confirmed to be important for improving the current modeling of the Sun, here in particular in terms of spectral line formation and of deriving consistent chemical abundances. These results may shed further light on the still controversial issue regarding the precise value of the solar oxygen abundance.

  19. The Magnification of Atomic Lines Intensity Originated by laser Breakdown in Ultrasound Field

    NASA Astrophysics Data System (ADS)

    Bulanov, A. V.; Nagorny, I. G.

    Atomic lines of some chemical elements like sodium and magnesium were investigated for laser breakdown of water with the ultrasound field. The effect of magnification of these atomic lines resolution for salt water in ultrasound field was obtained. It is shown that the method of registration of acoustic emission from a breakdown zone allows to investigate thresholds and dynamics of laser breakdown which will be in accord with high-speed optical methods. The study revealed important practical applications of acoustic emission for breakdown and diagnostics of cavitation in opaque environments.

  20. Search for the l-forbidden beta decay /sup 207/Tl. -->. /sup 207/Pb(570 keV)

    SciTech Connect

    Hindi, M.M.; Adelberger, E.G.; Kellogg, S.E.; Murakami, T.

    1988-09-01

    We have searched for the l-forbidden beta decay of /sup 207/Tl to the first excited state of /sup 207/Pb by looking for 570-keV ..gamma.. rays following the decay of /sup 207/Tl. We find a branching ratio of (2.4 +- 5.6) x 10/sup -7/ per /sup 207/Tl decay. This limit could provide a test for calculations of core polarization, meson exchange, and ..delta.. excitation effects. We also find a branch of (0.54 +- 0.05)% for the l-forbidden M1 transition /sup 207/Pb(898,(3/2/sup -/..-->..570,(5/2/sup -/) and measure the intensities of ..gamma.. rays emitted following the decay of /sup 211/Pb.

  1. Cold Chemistry In TMC-CP: Temperature Deduced From HC9N Line Intensities

    NASA Astrophysics Data System (ADS)

    Moats, S. J.; Langston, Glen; Soehl, D. C.

    2009-01-01

    We present a model for the temperature of the Taurus Molecular Cloud (TMC) Cyanopolyene Peak (CP). This model is based on a fit to molecular line observations with the Robert C. Byrd Green Bank Telescope. We find this region to be very cold, with temperature of approximately 3 Kelvin. The TMC-CP region is of great interest because of its known high abundance of large organic molecules. Large molecular structures have been observed within TMC-1 by various authors (Pratrap et al 1997, Dickens et al 2001, and Turner et al 2005). The detection of large molecules, such as HC5N, HC7N, and HC9N, suggests that smaller amino acids could also form in the interstellar medium. Amino acids are essential to life found on earth, and it is highly possible that early biological molecules had their origins within the molecular clouds of the interstellar medium. We observed a sequence of HC9N and HC7N line transitions, in the frequency range 11 to 15 GHz, to estimate the temperature of the molecular line emission region. We present radio images of the structure of TMC from our search for the molecules HC11N and HC13N. Finally, we present upper limits on the abundance of selected molecules, based on averaging observations of many spectral lines in the manner described by Langston and Turner (2007). The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  2. A region of intense plasma wave turbulence on auroral field lines

    NASA Technical Reports Server (NTRS)

    Gurnett, D. A.; Frank, L. A.

    1976-01-01

    This report presents a detailed study of the plasma wave turbulence observed by HAWKEYE-1 and IMP-6 on high latitude auroral field lines and investigates the relationship of this turbulence to magnetic field and plasma measurements obtained in the same region.

  3. Environmental sensitivity differs between rabbit lines selected for reproductive intensity and longevity.

    PubMed

    Savietto, D; Cervera, C; Blas, E; Baselga, M; Larsen, T; Friggens, N C; Pascual, J J

    2013-12-01

    To better understand the mechanisms that allow some animals to sustain their productive effort in harsh environmental conditions, rabbit does from two selection lines (LP and V) were housed in normal (NC), nutritional (NF) or heat (HC) challenging environmental conditions from first to third partum. The LP line (n=85) was founded on reproductive longevity criteria by selecting does from commercial farms that had a minimum of 25 partum with more than 7.5 kits born alive per parity. Line V (n=79) was constituted from four specialised maternal lines into a composite synthetic line and then selected by litter size at weaning for 36 generations. Female rabbits in NC and NF environments were housed at normal room temperature (18°C to 24°C) and fed with control [11.6 MJ digestible energy (DE)/kg dry matter (DM)] or low-energy diets (9.1 MJ DE/kg DM). HC does were housed at high room temperatures (25°C to 35°C) and fed the control diet. Female rabbits in the HC and NF environments ingested 11.5% and 6% less DE than NC does, respectively (P<0.05). These differences between environments occurred in both lines, with the differences being higher for LP than for V does (+6%; P<0.05). Milk yield responses followed those of energy intake also being higher for LP does (+21.3 g/day; P<0.05). The environmental conditions did not affect the perirenal fat thickness (PFT), but a genotype by environment interaction was observed. In NC and HC, the PFT was higher for line V (+0.23 and +0.35 mm, respectively; P<0.05) than for LP does, but this was not the case at NF (-0.01 mm). Moreover, the PFT evolution was different between them. In the NC environment, LP does used the accreted PFT in late lactation (-0.29 mm), whereas V does did not (-0.08 mm). Conversely, in the HC environment, LP does showed a flat PFT evolution in late lactation, whereas V does accumulated PFT. In the NF environment, LP and V does had a similar PFT evolution. There was also a litter size reduction for V does of

  4. HST imaging of the inner 3 arcseconds of NGC 1068 in the light of forbidden O III 5007 A

    NASA Technical Reports Server (NTRS)

    Evans, I. N.; Kinney, A. L.; Ford, H. C.; Antonucci, R. R. J.; Armus, L.

    1991-01-01

    The Planetary Camera aboard HST has been used to obtain a high spatial resolution forbidden O III 5007 A image of the nucleus of the barred spiral galaxy NGC 1068. This image shows more detail than any previously published images and resolves the NLR into several distinct clouds arranged in an apparently conical geometry. The individual emission-line regions appear to be resolved with sizes of 0.1-0.2 arcsec. There is a strong apparent correspondence between the 1.3 cm radio structure and several of the forbidden O III 5007 A clouds, although there are also bright emission-line clouds for which there are no radio counterparts. In particular, the radio 'triple' of Ulvestad et al. (1987) appears to correspond directly to the forbidden O III 5007 A clouds A-D. It is concluded that the distribution of the clouds is consistent with ionization core models. The hidden nucleus is located somewhere in the southern radio component and may be coincident with the H2O megamaser.

  5. Monitoring the Intensity of Ice Formation on Overhead Electric Power Lines and Contact Networks

    SciTech Connect

    Titov, D. E.; Ugarov, G. G.; Soshinov, A. G.

    2015-05-15

    The conditions for ice to form on a conductor are explained. A hypothesis on the existence of a functional relation between the rate of growth of a mass deposited on a non-live conductor, the dew and desublimation points, and the temperature of the wire surface when there is no wind is suggested and proved. Equations for determining the density, maximum possible mass of the coating and the intensity with which they are formed are proposed, which take into account the temperature of the conductor, the temperature and humidity of the air, the direction and velocity of the wind and the electric field strength of the conductor. The equations are the basis of a proposed thermodynamic method of monitoring the intensity of ice formation. Versions of a technical method and algorithms of the functioning of ice-formation monitoring are proposed.

  6. A brief review of the intensity of lines 3C and 3D in neon-like Fe XVII

    SciTech Connect

    Brown, G V

    2007-06-13

    X-ray emission from neon-like Fe XVII has been measured with high-resolution spectrometers from laboratory or celestial sources for nearly seven decades. Two of the strongest lines regularly identified in these spectra are the {sup 1}P{sub 1} {yields} {sup 1}S{sub 0} resonance, and {sup 3}D{sub 1} {yields} {sup 1}S{sub 0} intercombination line, known as 3C and 3D, respectively. This paper gives a brief overview of measurements of the intensities of the lines 3C and 3D from laboratory and celestial sources, and their comparison to model calculations, with an emphasis on measurements completed using an electron beam ion trap. It includes a discussion of the measured absolute cross sections compared to results from modern atomic theory calculations, as well as the diagnostic utility of the relative intensity, R = I{sub 3C}/I{sub 3D}, as it applies to the interpretation of spectra measured from the Sun and extra-Solar sources.

  7. Atomic Data and Spectral Line Intensities for Be-like Ions

    NASA Technical Reports Server (NTRS)

    Bhatia, Anand; Landi, E.

    2008-01-01

    Atomic data and collision rates are needed to model the spectrum of optically thin astrophysical sources. Recent observations from solar instrumentation such as SOH0 and Hinode have revealed the presence of hosts of lines emitted by high-energy configurations from ions belonging to the Be-like to the 0-like isoelectronic sequences. Data for such configurations are often unavailable in the literature. We have started a program to calculate the atomic parameters and rates for the high-energy configurations of Be-like ions of the type ls2.21.nl' where n=3,4,5. We report on the results of this project and on the diagnostic application of the predicted spectral lines.

  8. Laser-driven beam lines for delivering intensity modulated radiation therapy with particle beams

    PubMed Central

    Hofmann, Kerstin M; Schell, Stefan; Wilkens, Jan J

    2012-01-01

    Abstract Laser-accelerated particles are a promising option for radiation therapy of cancer by potentially combining a compact, cost-efficient treatment unit with the physical advantages of charged particle beams. To design such a treatment unit we consider different dose delivery schemes and analyze the necessary devices in the required particle beam line for each case. Furthermore, we point out that laser-driven treatment units may be ideal tools for motion adaptation during radiotherapy. Reasons for this are the potential of a flexible gantry and the time structure of the beam with high particle numbers in ultrashort bunches. One challenge that needs to be addressed is the secondary radiation produced in several beam line elements. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) PMID:22930653

  9. Laser-driven beam lines for delivering intensity modulated radiation therapy with particle beams.

    PubMed

    Hofmann, Kerstin M; Schell, Stefan; Wilkens, Jan J

    2012-11-01

    Laser-accelerated particles are a promising option for radiation therapy of cancer by potentially combining a compact, cost-efficient treatment unit with the physical advantages of charged particle beams. To design such a treatment unit we consider different dose delivery schemes and analyze the necessary devices in the required particle beam line for each case. Furthermore, we point out that laser-driven treatment units may be ideal tools for motion adaptation during radiotherapy. Reasons for this are the potential of a flexible gantry and the time structure of the beam with high particle numbers in ultrashort bunches. One challenge that needs to be addressed is the secondary radiation produced in several beam line elements.

  10. Laser-driven beam lines for delivering intensity modulated radiation therapy with particle beams

    SciTech Connect

    Hofmann, K. M.; Schell, S.; Wilkens, J. J.

    2013-07-26

    Laser-accelerated particles can provide a promising opportunity for radiation therapy of cancer. Potential advantages arise from combining a compact, cost-efficient treatment unit with the physical advantages in dose delivery of charged particle beams. We consider different dose delivery schemes and the required devices to design a possible treatment unit. The secondary radiation produced in several beam line elements remains a challenge to be addressed.

  11. Laser-driven beam lines for delivering intensity modulated radiation therapy with particle beams

    NASA Astrophysics Data System (ADS)

    Hofmann, K. M.; Schell, S.; Wilkens, J. J.

    2013-07-01

    Laser-accelerated particles can provide a promising opportunity for radiation therapy of cancer. Potential advantages arise from combining a compact, cost-efficient treatment unit with the physical advantages in dose delivery of charged particle beams. We consider different dose delivery schemes and the required devices to design a possible treatment unit. The secondary radiation produced in several beam line elements remains a challenge to be addressed.

  12. On-line depth measurement for laser-drilled holes based on the intensity of plasma emission

    NASA Astrophysics Data System (ADS)

    Ho, Chao-Ching; Chiu, Chih-Mu; Chang, Yuan-Jen; Hsu, Jin-Chen; Kuo, Chia-Lung

    2014-09-01

    The direct time-resolved depth measurement of blind holes is extremely difficult due to the short time interval and the limited space inside the hole. This work presents a method that involves on-line plasma emission acquisition and analysis to obtain correlations between the machining processes and the optical signal output. Given that the depths of laser-machined holes can be estimated on-line using a coaxial photodiode, this was employed in our inspection system. Our experiments were conducted in air under normal atmospheric conditions without gas assist. The intensity of radiation emitted from the vaporized material was found to correlate with the depth of the hole. The results indicate that the estimated depths of the laser-drilled holes were inversely proportional to the maximum plasma light emission measured for a given laser pulse number.

  13. Simple strategies to reduce healthcare associated infections in the neonatal intensive care unit: line, tube, and hand hygiene.

    PubMed

    Graham, Philip L

    2010-09-01

    This article describes strategies to prevent 2 important healthcare associated infections in the neonatal intensive care unit: central line-associated bloodstream infections and catheter-associated urinary tract infections. Hand hygiene is discussed as the cornerstone for prevention of all healthcare associated infections. Specific recommendations for education and training of health care personnel who insert and maintain central venous catheters and urinary tract catheters are made and best practices for insertion and maintenance of these catheters are discussed. Throughout this article, the emphasis is on prevention of these high morbidity and mortality healthcare associated infections.

  14. Anisotropic x-ray anomalous diffraction and forbidden reflections

    SciTech Connect

    Carra, P.; Thole, B.T. )

    1994-10-01

    In this paper the authors present a general analysis of resonant elastic scattering of x rays. The approach exploits crystal symmetry, scattering geometry, and polarization. Extinction rules, their breaking, and the observation of forbidden reflections are discussed. As an application, a detailed description of the experiment performed by Finkelstein, Shen, and Shastri at the iron [ital K] edge in [alpha] Fe[sub 2]O[sub 3] (hematite) is reported.

  15. Effect of structural forbiddenness in fusion of heavy nuclei

    NASA Astrophysics Data System (ADS)

    Adamian, G. G.; Antonenko, N. V.; Tchuvil'Sky, Yu. M.

    1999-04-01

    With a microscopic approach based on the formalism of irreducible representations of the SU(3) group the influence of structural forbiddenness on the fusion of heavy nuclei and the dinuclear system phenomenon are investigated for different symmetric and asymmetric reactions used in the synthesis of heavy and superheavy nuclei. The energy thresholds for complete fusion in relative distance and mass asymmetry degrees of freedom are estimated.

  16. The rise and fall of horror autotoxicus and forbidden clones.

    PubMed

    Jennette, J Charles; Falk, Ronald J

    2010-09-01

    Cui and associates show that healthy individuals have natural autoantibodies (NAAs) specific for myeloperoxidase, proteinase 3, and glomerular basement membrane (GBM) with the same specificity as anti-neutrophil cytoplasmic antibodies and anti-GBM antibodies that are pathogenic. Although Ehrlich proposed horror autotoxicus and Burnet envisioned elimination of forbidden clones, NAAs are present in all healthy individuals and play beneficial homeostatic roles. Pathogenic autoimmunity is dysregulation of natural homeostatic autoimmunity rather than onset of a previously absent self-recognition.

  17. Shape of solitons in classically forbidden states - 'Lorentz expansion'

    NASA Technical Reports Server (NTRS)

    Guinea, F.; Peierls, R. E.; Schrieffer, R.

    1986-01-01

    The shape of extended objects in classically forbidden regions is shown to undergo expansion analogous to Lorentz contraction of a relativistic body of finite velocities. The problem of two interacting Dirac particles moving in one dimension is solved explicitly and the results are generalized to soliton solutions of field theories. An estimate of the effect on tunneling rates is also given, including solitons in (CH)z.

  18. Search for the CP forbidden decay eta-->4pi(0)

    PubMed

    Prakhov; Tippens; Allgower; Bekrenev; Berger; Briscoe; Clajus; Comfort; Craig; Grosnick; Huber; Isenhower; Knecht; Koetke; Koulbardis; Kozlenko; Kruglov; Kycia; Lolos; Lopatin; Manley; Marusic; Manweiler; McDonald; Nefkens; Olmsted

    2000-05-22

    We report the first determination of the upper limit for the branching ratio of the CP forbidden decay eta-->4pi(0). No events were observed in a sample of 3.0x10(7) eta decays. The experiment was performed with the Crystal Ball multiphoton spectrometer installed in a separated pi(-) beam at the AGS (Alternating Gradient Synchrotron). At the 90% confidence limit, B(eta-->4pi(0))

  19. SF_6: the Forbidden Band Unveiled

    NASA Astrophysics Data System (ADS)

    Boudon, V.; Manceron, L.; Kwabia-Tchana, F.; Roy, P.

    2013-06-01

    Sulfur hexafluoride (SF_6) is a greenhouse gas of anthropogenic origin, whose strong infrared absorption in the ν_3 S-F stretching region near 948 cm^{-1} induces a global warming potential 23900 times bigger than CO_2. This heavy species features many hot bands at room temperature (at which the ground state population is only 30 %), especially those originating from the v_6=1 state. Unfortunately, the ν_6 band itself (near 347 cm^{-1}) being, in first approximation, both infrared and Raman inactive, no reliable information could be obtained about it up to now. A long time ago, some authors suggested that this band may be slightly activated through Coriolis interaction and may appear as a very faint band, with an integrated intensity about 2 millionths of that of ν_3. Using a new cryogenic multipass cell with 93 m optical path length and regulated at 165± 2 K temperature, we recorded a spectrum of the ν_6 far-infrared region thanks to the performances of the AILES Beamline at the SOLEIL french synchrotron facility. Low temperature was used to avoid the presence of the 2ν_6-ν_6 hot band and to reduce the neighboring, stronger ν_4-ν_2 difference band. We are thus able to confirm that the small feature in this region, previously viewed at low-resolution is indeed ν_6. We present its fully resolved spectrum. It appears to be activated thanks to unidentified faint interactions resulting in the presence of a first-order dipole moment term that induces unusual selection rules. This spectrum was analyzed thanks to the XTDS software package, leading to accurate molecular spectroscopic parameters that should be useful to model the hot bands of SF_6. W. B. Person, B. J. Krohn, J. Mol. Spectrosc. {98}, 229-257 (1983), C. Chappados, G. Birnbaum, J. Mol. Spectrosc. {105}, 206-214 (1984). Ch. Wenger, V. Boudon, M. Rotger, M. Sanzharov and J.-P. Champion, J. Mol. Spectrosc., {251} 102-113 (2008).

  20. Resolving the forbidden band of SF6.

    PubMed

    Boudon, V; Manceron, L; Kwabia Tchana, F; Loëte, M; Lago, L; Roy, P

    2014-01-28

    D and the ν6 integrated intensity to be 0.0035 km mol(-1).

  1. Aerodynamic Mixing Downstream from Line Source of Heat in High-intensity Sound Field

    NASA Technical Reports Server (NTRS)

    Mickelson, William R; Baldwin, Lionel V

    1956-01-01

    Theory and measurement showed that the heat wake downstream from a line source is displaced by a transverse standing sound wave in a manner similar to a flag waving in a harmonic mode. With a 147 db, 104 cps standing wave, time-mean temperatures were reduced by an order of magnitude except near the displacement-pattern nodal points. The theory showed that a 161 db, 520 cps standing wave considerably increased the mixing in both the time-mean and instantaneous senses.

  2. Symmetry forbidden vibronic spectra and internal conversion in benzene.

    PubMed

    Li, Jun; Lin, Chih-Kai; Li, Xiang Yuan; Zhu, Chao Yuan; Lin, Sheng Hsien

    2010-12-07

    The spectra of symmetry-forbidden transitions and internal conversion were investigated in the present work. Temperature dependence was taken into account for the spectra simulation. The vibronic coupling, essential in the two processes, was calculated based on the Herzberg-Teller theory within the Born-Oppenheimer approximation. The approach was employed for the symmetry-forbidden absorption/fluorescence, and internal conversion between 1(1)A(1g) and 1(1)B(2u) states in benzene. Vibrational frequencies, normal coordinates, electronic transition dipole moments, and non-adiabatic coupling matrix elements were obtained by ab initio quantum chemical methods. The main peaks, along with the weak peaks, were in good agreement with the observed ones. The rate constant of the 1(1)A(1g)← 1(1)B(2u) internal conversion was estimated within the order of 10(3) s(-1). This could be regarded as the lower limit (about 4.8 × 10(3) s(-1)) of the internal conversion. It is stressed that the distortion effect was taken into account both in the symmetry-forbidden absorption/fluorescence, and the rate constants of internal conversion in the present work. The distortion effects complicate the spectra and increase the rate constants of internal conversion.

  3. Quantitative Kα line spectroscopy for energy transport in ultra-intense laser plasma interaction

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Nishimura, H.; Fujioka, S.; Arikawa, Y.; Nakai, M.; Chen, H.; Park, J.; Williams, G. J.; Ozaki, T.; Shiraga, H.; Kojima, S.; Johzaki, T.; Sunahara, A.; Miyanaga, N.; Kawanaka, J.; Nakata, Y.; Jitsuno, T.; Azechi, H.

    2016-03-01

    Absolute Ka line spectroscopy is proposed for studying laser-plasma interactions taking place in the cone-guided fast ignition targets. X-ray spectra ranging from 20 to 100 keV were quantitatively measured with a Laue spectrometer. The absolute sensitivities of the Laue spectrometer system were calibrated using pre-characterized laser-produced x-ray sources and radioisotopes. The integrated reflectivity for the crystal is in good agreement with predictions by an open code for x-ray diffraction. The energy transfer efficiency from incident laser beams to hot electrons, as the energy transfer agency, is derived as a consequence of this work. The absolute yield of Au and Ta Ka lines were measured in the fast ignition experimental campaign performed at Institute of Laser Engineering, Osaka University. Applying the hot electron spectrum information from the electron spectrometer, an energy transfer efficiency of the incident LFEX [1], a kJ-class PW laser, to hot electrons was derived for a planar and cone-guided geometry.

  4. Tracking objects outside the line of sight using 2D intensity images

    PubMed Central

    Klein, Jonathan; Peters, Christoph; Martín, Jaime; Laurenzis, Martin; Hullin, Matthias B.

    2016-01-01

    The observation of objects located in inaccessible regions is a recurring challenge in a wide variety of important applications. Recent work has shown that using rare and expensive optical setups, indirect diffuse light reflections can be used to reconstruct objects and two-dimensional (2D) patterns around a corner. Here we show that occluded objects can be tracked in real time using much simpler means, namely a standard 2D camera and a laser pointer. Our method fundamentally differs from previous solutions by approaching the problem in an analysis-by-synthesis sense. By repeatedly simulating light transport through the scene, we determine the set of object parameters that most closely fits the measured intensity distribution. We experimentally demonstrate that this approach is capable of following the translation of unknown objects, and translation and orientation of a known object, in real time. PMID:27577969

  5. Effective line intensity measurements of trans-nitrous acid (HONO) of the ν1 band near 3600 cm-1 using laser difference-frequency spectrometer

    NASA Astrophysics Data System (ADS)

    Maamary, Rabih; Fertein, Eric; Fourmentin, Marc; Dewaele, Dorothée; Cazier, Fabrice; Chen, Changshui; Chen, Weidong

    2017-07-01

    We report on the measurements of the effective line intensities of the ν1 fundamental band of trans-nitrous acid (trans-HONO) in the infrared near 3600 cm-1 (2.78 μm). A home-made widely tunable laser spectrometer based on difference-frequency generation (DFG) was used for this study. The strengths of 28 well-resolved absorption lines of the ν1 band were determined by scaling their absorption intensities to the well referenced absorption line intensity of the ν3 band of trans-HONO around 1250 cm-1 recorded simultaneously with the help of a DFB quantum cascade laser (QCL) spectrometer. The maximum measurement uncertainty of 12% in the line intensities is mainly determined by the uncertainty announced in the referenced line intensities, while the measurement precision in frequency positions of the absorption lines is better than 6×10-4 cm-1. The cross-measurement carried out in the present work allows one to perform intensity calibration using well referenced line parameters.

  6. The [NeIV] Lines in High Excitation Gaseous Nebulae.

    PubMed

    Aller, L H

    1970-04-01

    The "forbidden" lines of three times ionized neon are among the most precious indicators of electron temperature and excitation. They are also predicted to be among the strongest lines observed in the far ultraviolet spectra of high excitation nebulae.

  7. Designing a Method for AN Automatic Earthquake Intensities Calculation System Based on Data Mining and On-Line Polls

    NASA Astrophysics Data System (ADS)

    Liendo Sanchez, A. K.; Rojas, R.

    2013-05-01

    Seismic intensities can be calculated using the Modified Mercalli Intensity (MMI) scale or the European Macroseismic Scale (EMS-98), among others, which are based on a serie of qualitative aspects related to a group of subjective factors that describe human perception, effects on nature or objects and structural damage due to the occurrence of an earthquake. On-line polls allow experts to get an overview of the consequences of an earthquake, without going to the locations affected. However, this could be a hard work if the polls are not properly automated. Taking into account that the answers given to these polls are subjective and there is a number of them that have already been classified for some past earthquakes, it is possible to use data mining techniques in order to automate this process and to obtain preliminary results based on the on-line polls. In order to achieve these goal, a predictive model has been used, using a classifier based on a supervised learning techniques such as decision tree algorithm and a group of polls based on the MMI and EMS-98 scales. It summarized the most important questions of the poll, and recursive divides the instance space corresponding to each question (nodes), while each node splits the space depending on the possible answers. Its implementation was done with Weka, a collection of machine learning algorithms for data mining tasks, using the J48 algorithm which is an implementation of the C4.5 algorithm for decision tree models. By doing this, it was possible to obtain a preliminary model able to identify up to 4 different seismic intensities with 73% correctly classified polls. The error obtained is rather high, therefore, we will update the on-line poll in order to improve the results, based on just one scale, for instance the MMI. Besides, the integration of automatic seismic intensities methodology with a low error probability and a basic georeferencing system, will allow to generate preliminary isoseismal maps

  8. First on-line isotopic characterization of N2O above intensively managed grassland

    NASA Astrophysics Data System (ADS)

    Wolf, B.; Merbold, L.; Decock, C.; Tuzson, B.; Harris, E.; Six, J.; Emmenegger, L.; Mohn, J.

    2015-04-01

    The analysis of the four main isotopic N2O species (14N14N16O, 14N15N16O, 15N14N16O, 14N14N18O) and especially the intramolecular distribution of 15N ("site preference", SP) has been suggested as a tool to distinguish source processes and to help constrain the global N2O budget. However, current studies suffer from limited spatial and temporal resolution capabilities due to the combination of discrete flask sampling with subsequent laboratory-based mass-spectrometric analysis. Quantum cascade laser absorption spectroscopy (QCLAS) allows the selective high-precision analysis of N2O isotopic species at trace levels and is suitable for in situ measurements. Here, we present results from the first field campaign, conducted on an intensively managed grassland site in central Switzerland. N2O mole fractions and isotopic composition were determined in the atmospheric surface layer (at 2.2 m height) at a high temporal resolution with a modified state-of-the-art laser spectrometer connected to an automated N2O preconcentration unit. The analytical performance was determined from repeated measurements of a compressed air tank and resulted in measurement repeatability of 0.20, 0.12 and 0.11‰ for δ15Nα, δ15Nβ and δ18O, respectively. Simultaneous eddy-covariance N2O flux measurements were used to determine the flux-averaged isotopic signature of soil-emitted N2O. Our measurements indicate that, in general, nitrifier-denitrification and denitrification were the prevalent sources of N2O during the campaign and that variations in isotopic composition were due to alterations in the extent to which N2O was reduced to N2 rather than to other pathways, such as hydroxylamine oxidation. Management and rewetting events were characterized by low values of the intramolecular 15N site preference (SP), δ15Nbulk and δ18O, suggesting that nitrifier-denitrification and incomplete heterotrophic bacterial denitrification responded most strongly to the induced disturbances. The flux

  9. First on-line isotopic characterization of N2O emitted from intensively managed grassland

    NASA Astrophysics Data System (ADS)

    Wolf, B.; Merbold, L.; Decock, C.; Tuzson, B.; Harris, E.; Six, J.; Emmenegger, L.; Mohn, J.

    2015-01-01

    The analysis of the four main isotopic N2O species (14N14N16O, 14N15N16O, 15N14N16O, 14N14N18O) and especially the intramolecular distribution of 15N (site preference, SP) has been suggested as a tool to distinguish source processes and to help constrain the global N2O budget. However, current studies suffer from limited spatial and temporal resolution capabilities due to the combination of discrete flask sampling with subsequent laboratory-based mass spectrometric analysis. Quantum cascade laser absorption spectroscopy (QCLAS) allows selective high-precision analysis of N2O isotopic species at trace levels and is suitable for in situ measurements. Here, we present results from the first field campaign, conducted on an intensively managed grassland in central Switzerland. N2O mole fractions and isotopic composition were determined in the atmospheric surface layer (2 m height) at high temporal resolution with a modified state-of-the-art laser spectrometer connected to an automated N2O preconcentration unit. The analytical performance was determined from repeated measurements of a compressed air tank and resulted in measurement repeatability of 0.20, 0.12 and 0.11‰ for δ15Nα, δ15Nβ and δ18O, respectively. Simultaneous eddy-covariance N2O flux measurements were used to determine the flux-averaged isotopic signature of soil-emitted N2O. Our measurements indicate that in general, nitrifier-denitrification and denitrification were the prevalent sources of N2O during the campaign, and that variations in isotopic composition were rather due to alterations in the extent to which N2O was reduced to N2, than other pathways such as hydroxylamine oxidation. Management and rewetting events were characterized by low values of the intra-molecular 15N site preference (SP), δ15Nbulk and δ18O, suggesting nitrifier denitrification and incomplete heterotrophic bacterial denitrification responded most strongly to the induced disturbances. Flux-averaged isotopic composition of N

  10. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    NASA Astrophysics Data System (ADS)

    Zhang, Xu; Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming; Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN-LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  11. Metal-Substrate-Mediated Plasmon Hybridization in a Nanoparticle Dimer for Photoluminescence Line-Width Shrinking and Intensity Enhancement.

    PubMed

    Li, Guang-Can; Zhang, Yong-Liang; Jiang, Jing; Luo, Yu; Lei, Dang Yuan

    2017-03-28

    Metal-film-coupled nanoparticles with subnanometer particle-film gaps possess an ultrasmall mode volume, responsible for a variety of intriguing phenomena in plasmonic nanophotonics. Due to the large radiative loss associated with dipolar coupling, however, the plasmonic-film-coupled nanocavities usually feature a low-quality factor, setting an ultimate limit of the increased light-matter interaction strength. Here, we demonstrate a plasmonic nanocavity composed of a metal-film-coupled nanoparticle dimer, exhibiting a significantly improved quality factor. Compared to a silica-supported dimer, the spectral line width of the nanocavity plasmon resonance is reduced by a factor of ∼4.6 and is even smaller than its monomer counterpart (∼30% reduction). Comprehensive theoretical analyses reveal that this pronounced resonance narrowing effect can be attributed to intense film-mediated plasmon hybridization between the bonding dipolar and quadrupolar gap modes in the dimer. More importantly, the invoking of the dark quadrupole resonance leads to a giant photoluminescence intensity enhancement (∼200 times) and dramatic emission line-width narrowing (∼4.6 times), compared to the silica-supported dimer. The similar spectral characteristics of the measured plasmonic scattering and photoluminescence emission indicate that the radiative decay of the coupled plasmons in the nanocavity is the origin of the observed photoluminescence, consistent with a proposed phenomenological model. Numerical calculations show that the intensity enhancement is mainly contributed by the dimer-film gap rather than the interparticle gap. These findings not only shed more light on the hybridized interaction between plasmon modes but also deepen the understanding of photoluminescence emission in coupled plasmonic nanostructures.

  12. Implementation of intensity ratio change and line-of-sight rate change algorithms for imaging infrared trackers

    NASA Astrophysics Data System (ADS)

    Viau, C. R.

    2012-06-01

    The use of the intensity change and line-of-sight (LOS) change concepts have previously been documented in the open-literature as techniques used by non-imaging infrared (IR) seekers to reject expendable IR countermeasures (IRCM). The purpose of this project was to implement IR counter-countermeasure (IRCCM) algorithms based on target intensity and kinematic behavior for a generic imaging IR (IIR) seeker model with the underlying goal of obtaining a better understanding of how expendable IRCM can be used to defeat the latest generation of seekers. The report describes the Intensity Ratio Change (IRC) and LOS Rate Change (LRC) discrimination techniques. The algorithms and the seeker model are implemented in a physics-based simulation product called Tactical Engagement Simulation Software (TESS™). TESS is developed in the MATLAB®/Simulink® environment and is a suite of RF/IR missile software simulators used to evaluate and analyze the effectiveness of countermeasures against various classes of guided threats. The investigation evaluates the algorithm and tests their robustness by presenting the results of batch simulation runs of surface-to-air (SAM) and air-to-air (AAM) IIR missiles engaging a non-maneuvering target platform equipped with expendable IRCM as self-protection. The report discusses how varying critical parameters such track memory time, ratio thresholds and hold time can influence the outcome of an engagement.

  13. Water absorption lines, 931-961 nm - Selected intensities, N2-collision-broadening coefficients, self-broadening coefficients, and pressure shifts in air

    NASA Technical Reports Server (NTRS)

    Giver, L. P.; Gentry, B.; Schwemmer, G.; Wilkerson, T. D.

    1982-01-01

    Intensities were measured for 97 lines of H2O vapor between 932 and 961 nm. The lines were selected for their potential usefulness for remote laser measurements of H2O vapor in the earth's atmosphere. The spectra were obtained with several different H2O vapor abundances and N2 broadening gas pressures; the spectral resolution was 0.046/cm FWHM. Measured H2O line intensities range from 7 x 10 to the -25th to 7 x 10 to the -22nd/cm per (molecules/sq cm). H2O self-broadening coefficients were measured for 13 of these strongest lines; the mean value was 0.5/cm per atm. N2-collision-broadening coefficients were measured for 73 lines, and the average was 0.11 cm per atm HWHM. Pressure shifts in air were determined for a sample of six lines between 948 and 950 nm; these lines shift to lower frequency by an amount comparable to 0.1 of the collision-broadened widths measured in air or N2. The measured intensities of many lines of 300-000 band are much larger than expected from prior computations, in some cases by over an order of magnitude. Coriolis interactions with the stronger 201-000 band appear to be the primary cause of the enhancement of these line intensities.

  14. Optical emission-line properties of evolved galactic supernova remnants

    NASA Technical Reports Server (NTRS)

    Fesen, R. A.; Blair, W. P.; Kirshner, R. P.

    1985-01-01

    New optical spectrophotometric data are presented for the supernova remnants CTB 1, OA 184, VRO 42.05.01, S147, the Monoceros Loop, G206.9 + 2.3, and G65.3 + 5.7. These data are combined with published spectral data to study some of the general properties of evolved galactic supernova remnants. It is found that (1) O I and O II forbidden line strengths, when used in conjunction with the usual H-alpha S II forbidden line ratio test, provide an excellent additional diagnostic for discriminating remnants from H II regions; (2) the line ratios H-alpha forbidden line N II, H-alpha forbidden line S II, and forbidden line S II 6717/6731 A generally do not vary substantially among the filaments of an individual remnant; and (3) the observed correlation of forbidden line N II/H-alpha with S II forbidden line 6717/6731 A in remnants is the result of observational selection rather than of evolutionary effects. A galactic nitrogen abundance gradient of d log (N/H)/dR = -0.088 dex/kpc, which is in agreement with that derived from H II regions. However, no abundance gradients for oxygen or sulfur are indicated from the remnant data.

  15. Critical Reexamination of Resonant Soft X-Ray Bragg Forbidden Reflections in Magnetite

    SciTech Connect

    Wilkins, S.B.; Di Matteo, S.; Beale, T.A.W.; Joly, Y.; Mazzoli, C.; Hatton, P.D.; Bencok, P.; Yakhou, F.; Brabers, V.A.M.

    2009-05-01

    Magnetite, Fe{sub 3}O{sub 4}, displays a highly complex low-temperature crystal structure that may be charge and orbitally ordered. Many of the recent experimental claims of such ordering rely on resonant soft x-ray diffraction at the oxygen K and iron L edges. We have reexamined this system and undertaken soft x-ray diffraction experiments on a high-quality single crystal. Contrary to previous claims in the literature, we show that the intensity observed at the Bragg forbidden (001/2){sub c} reflection can be explained purely in terms of the low-temperature structural displacements around the resonant atoms. This does not necessarily mean that magnetite is not charge or orbitally ordered but rather that the present sensitivity of resonant soft x-ray experiments does not allow conclusive demonstration of such ordering.

  16. Observation of the 5 p3 /2→6 p3 /2 electric-dipole-forbidden transition in atomic rubidium using optical-optical double-resonance spectroscopy

    NASA Astrophysics Data System (ADS)

    Ponciano-Ojeda, F.; Hernández-Gómez, S.; López-Hernández, O.; Mojica-Casique, C.; Colín-Rodríguez, R.; Ramírez-Martínez, F.; Flores-Mijangos, J.; Sahagún, D.; Jáuregui, R.; Jiménez-Mier, J.

    2015-10-01

    Direct evidence of excitation of the 5 p3 /2→6 p3 /2 electric-dipole-forbidden transition in atomic rubidium is presented. The experiments were performed in a room-temperature rubidium cell with continuous-wave external cavity diode lasers. Optical-optical double-resonance spectroscopy with counterpropagating beams allows the detection of the nondipole transition free of Doppler broadening. The 5 p3 /2 state is prepared by excitation with a laser locked to the maximum F cyclic transition of the D2 line, and the forbidden transition is produced by excitation with a 911 nm laser. Production of the forbidden transition is monitored by detection of the 420 nm fluorescence that results from decay of the 6 p3 /2 state. Spectra with three narrow lines (≈13 MHz FWHM) with the characteristic F -1 , F , and F +1 splitting of the 6 p3 /2 hyperfine structure in both rubidium isotopes were obtained. The results are in very good agreement with a direct calculation that takes into account the 5 s →5 p3 /2 preparation dynamics, the 5 p3 /2→6 p3 /2 nondipole excitation geometry, and the 6 p3 /2→5 s1 /2 decay. The comparison also shows that the electric-dipole-forbidden transition is a very sensitive probe of the preparation dynamics.

  17. FE-XIII Infrared / FE-XIV Green Line Ratio Diagnostics (P55)

    NASA Astrophysics Data System (ADS)

    Srivastava, A. K.; et al.

    2006-11-01

    aks.astro.itbhu@gmail.com We consider the first 27-level atomic model of Fe XIII (5.9 < log Te < 6.4 K) to estimate its ground level populations, taking account of electron as well as proton collisional excitations and de-excitations, radiative cascades, radiative excitations and de-excitations. Radiative cascade is important but the effect of dilution factor is negligible at higher electron densities. The 3 P1-3P0 and 3P2-3P1 transitions in the ground configuration 3s2 3p2 of Fe XIII result in two forbidden coronal emission lines in the infrared region, namely 10747 Å and 10798 Å., while the 5303 Å green line is formed in the 3s2 3p 2 2 ground configuration of Fe XIV as a result of P3 / 2 - P1 / 2 magnetic dipole transition. The line-widths of appropriate pair of forbidden coronal emission lines observed simultaneously can be useful diagnostic tool to deduce temperature and non-thermal velocity in the large scale coronal structures using intensity ratios of the lines as the temperature signature, instead of assuming ion temperature to be equal to the electron temperature. Since the line intensity ratios IG5303/IIR10747 and IG5303/IIR10798 have very week density dependence, they are ideal monitors of temperature mapping in the solar corona.

  18. Effects of low intensity static electromagnetic radiofrequency fields on leiomyosarcoma and smooth muscle cell lines.

    PubMed

    Karkabounas, Spyridon; Havelas, Konstantinos; Kostoula, Olga K; Vezyraki, Patra; Avdikos, Antonios; Binolis, Jayne; Hatziavazis, George; Metsios, Apostolos; Verginadis, Ioannis; Evangelou, Angelos

    2006-01-01

    In this study we investigated the effects of low intensity static radiofrequency electromagnetic field (EMF) causing no thermal effects, on leiomyosarcoma cells (LSC), isolated from tumors of fifteen Wistar rats induced via a 3,4-benzopyrene injection. Electromagnetic resonance frequencies measurements and exposure of cells to static EMF were performed by a device called multi channel dynamic exciter 100 V1 (MCDE). The LSC were exposed to electromagnetic resonance radiofrequencies (ERF) between 10 kHz to 120 kHz, for 45 min. During a 24h period, after the exposure of the LSC to ERF, there was no inhibition of cells proliferation. In contrast, at the end of a 48 h incubation period, LSC proliferation dramatically decreased by more than 98% (P<0.001). At that time, the survived LSC were only 2% of the total cell population exposed to ERF, and under the same culture conditions showed significant decrease of proliferation. These cells were exposed once again to ERF for 45 min (totally 4 sessions of exposure, of 45 min duration each) and tested using a flow cytometer. Experiments as above were repeated five times. It was found that 45% of these double exposed to ERF, LSC (EMF cells) were apoptotic and only a small percentage 2%, underwent mitosis. In order to determinate their metastatic potential, these EMF cells were also counted and tested by an aggregometer for their ability to aggregate platelets and found to maintain this ability., since they showed no difference in platelet aggregation ability compared to the LSC not exposed to ERF (control cells). In conclusion, exposure of LSC to specific ERF, decreases their proliferation rate and induces cell apoptosis. Also, the LSC that survived after exposed to ERF, had a lower proliferation rate compared to the LSC controls (P<0.05) but did not loose their potential for metastases (platelet aggregation ability). The non-malignant SMC were not affected by the EMF exposure (P<0.4). The specific ERF generated from the MCDE

  19. Forbidden interval of propagation speed for exothermic chemical fronts.

    PubMed

    Leda, M; Lemarchand, A; Nowakowski, B

    2007-05-01

    We consider the propagation of an exothermic chemical front toward an unstable steady state. The hydrodynamic equations are solved numerically for increasing values of the activation energy of the reaction which controls the reaction front speed. For a large speed, the marginal stability criterion of the isothermal case is recovered. For a small speed, we observe two well-separated traveling waves: a heat front is preceding the reaction front. We find analytically a forbidden speed interval where the hydrodynamical system does not admit stationary traveling solutions.

  20. Polarization Studies of Resonant Forbidden Reflections in Liquid Crystals

    SciTech Connect

    Fernandes, P.; Barois, P.; Nguyen, H. T.; Wang, S. T.; Liu, Z. Q.; McCoy, B. K.; Huang, C. C.; Pindak, R.; Caliebe, W.

    2007-11-30

    We report the results of resonant x-ray diffraction experiments performed on thick films of a biaxial liquid crystal made of achiral bent-core molecules. Polarization properties of forbidden reflections are observed as a function of the sample rotation angle {phi} about the scattering vector Q for the first time on a fluid material. The experimental data are successfully analyzed within a tensor structure factor model by taking the nonperfect alignment of the liquid crystal into account. The local structure of the B{sub 2} mesophase is hence determined to be SmC{sub S}P{sub A}.

  1. SYNTHESIZED SPECTRA OF OPTICALLY THIN EMISSION LINES PRODUCED BY THE BIFROST STELLAR ATMOSPHERE CODE, INCLUDING NONEQUILIBRIUM IONIZATION EFFECTS: A STUDY OF THE INTENSITY, NONTHERMAL LINE WIDTHS, AND DOPPLER SHIFTS

    SciTech Connect

    Olluri, K.; Gudiksen, B. V.; Hansteen, V. H.; Pontieu, B. De

    2015-03-20

    In recent years realistic 3D numerical models of the solar atmosphere have become available. The models attempt to recreate the solar atmosphere and mimic observations in the best way, in order to make it possible to couple complicated observations with physical properties such as the temperatures, densities, velocities, and magnetic fields. We here present a study of synthetic spectra created using the Bifrost code in order to assess how well they fit with previously taken solar data. A study of the synthetic intensity, nonthermal line widths, Doppler shifts, and correlations between any two of these three components of the spectra first assuming statistical equilibrium is made, followed by a report on some of the effects nonequilibrium ionization will have on the synthesized spectra. We find that the synthetic intensities compare well with the observations. The synthetic observations depend on the assumed resolution and point-spread function (PSF) of the instrument, and we find a large effect on the results, especially for intensity and nonthermal line width. The Doppler shifts produce the reported persistent redshifts for the transition region (TR) lines and blueshifts for the upper TR and corona lines. The nonthermal line widths reproduce the well-known turnoff point around (2–3) × 10{sup 5} K, but with much lower values than those observed. The nonthermal line widths tend to increase with decreasing assumed instrumental resolution, also when nonequilibrium ionization is included. Correlations between the nonthermal line width of any two TR line studies as reported by Chae et al. are reproduced, while the correlations of intensity to line width are reproduced only after applying a PSF to the data. Doppler shift correlations reported by Doschek for the TR lines and correlations of Doppler shift to nonthermal line width of the Fe xii{sub 19.5} line reported by Doschek et al. are reproduced.

  2. Measurements of density dependent intensity ratios of extreme ultraviolet line emission from Fe X, XI, and XII

    NASA Astrophysics Data System (ADS)

    Shimizu, Erina; Ali, Safdar; Tsuda, Takashi; Sakaue, Hiroyuki A.; Kato, Daiji; Murakami, Izumi; Hara, Hirohisa; Watanabe, Tetsuya; Nakamura, Nobuyuki

    2017-05-01

    We report high-resolution density dependent intensity ratio measurements for middle charge states of iron in the extreme ultraviolet (EUV) spectral wavelength range of 160-200 Å. The measurements were performed at the Tokyo EBIT laboratory by employing a flat-field grazing incidence spectrometer installed on a low energy compact electron beam ion trap. The intensity ratios for several line pairs stemming from Fe X, Fe XI and Fe XII were extracted from spectra collected at the electron beam energies of 340 and 400 eV by varying the beam current between 7.5 and 12 mA at each energy. In addition, the effective electron densities were obtained experimentally by imaging the electron beam profile and ion cloud size with a pinhole camera and visible spectrometer, respectively. In this paper, the experimental results are compared with previous data from the literature and with the present calculations performed using a collisional-radiative model. Our experimental results show a rather good agreement with the calculations and previous reported results.

  3. Central-line-associated bloodstream infections in a resource-limited South African neonatal intensive care unit.

    PubMed

    Geldenhuys, C; Dramowski, A; Jenkins, A; Bekker, A

    2017-08-25

    The rate of central-line-associated bloodstream infection (CLABSI) in South African (SA) public sector neonatal intensive care units (NICUs) is unknown. Tygerberg Children's Hospital (TCH), Cape Town, introduced a neonatal CLABSI surveillance and prevention programme in August 2012. To describe CLABSI events and identify risk factors for development of CLABSI in a resource-limited NICU. A retrospective case-control study was conducted using prospectively collected NICU CLABSI events matched to four randomly selected controls, sampled from the NICU registry between 9 August 2012 and 31 July 2014. Clinical data and laboratory records were reviewed to identify possible risk factors, using stepwise forward logistic regression analysis. A total of 706 central lines were inserted in 530 neonates during the study period. Nineteen CLABSI events were identified, with a CLABSI rate of 5.9/1 000 line days. CLABSI patients were of lower gestational age (28 v. 34 weeks; p=0.003), lower median birth weight (1 170 g v. 1 975 g; p=0.014), had longer catheter dwell times (>4 days) (odds ratio (OR) 5.1 (95% confidence interval (CI) 1.0 - 25.4); p=0.04) and were more likely to have had surgery during their NICU stay (OR 3.5 (95% CI 1.26 - 10); p=0.01). Significant risk factors for CLABSI were length of stay >30 days (OR 20.7 (95% CI 2.1 - 203.2); p=0.009) and central-line insertion in the operating theatre (OR 8.1 (95% CI 1.2 - 54.7); p=0.03). Gram-negative pathogens predominated (12/22; 54%), with most isolates (10/12; 83%) exhibiting multidrug resistance. The TCH NICU CLABSI rate is similar to that reported from resource-limited settings, but exceeds that of high-income countries. Prolonged NICU stay and central-line insertion in the operating theatre were important risk factors for CLABSI development. Intensified neonatal staff training regarding CLABSI maintenance bundle elements and hand hygiene are key to reducing CLABSI rates.

  4. Radiative rates for forbidden M1 and E2 transitions of astrophysical interest in doubly ionized iron-peak elements

    NASA Astrophysics Data System (ADS)

    Fivet, V.; Quinet, P.; Bautista, M. A.

    2016-01-01

    Aims: Accurate and reliable atomic data for lowly ionized Fe-peak species (Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) are of paramount importance for analyzing the high-resolution astrophysical spectra currently available. The third spectra of several iron group elements have been observed in different galactic sources, such as Herbig-Haro objects in the Orion Nebula and stars like Eta Carinae. However, forbidden M1 and E2 transitions between low-lying metastable levels of doubly charged iron-peak ions have been investigated very little so far, and radiative rates for those lines remain sparse or nonexistent. We attempt to fill that gap and provide transition probabilities for the most important forbidden lines of all doubly ionized iron-peak elements. Methods: We carried out a systematic study of the electronic structure of doubly ionized Fe-peak species. The magnetic dipole (M1) and electric quadrupole (E2) transition probabilities were computed using the pseudo-relativistic Hartree-Fock (HFR) code of Cowan and the central Thomas-Fermi-Dirac-Amaldi potential approximation implemented in AUTOSTRUCTURE. This multiplatform approach allowed for consistency checks and intercomparison and has proven very useful in many previous works for estimating the uncertainties affecting the radiative data. Results: We present transition probabilities for the M1 and E2 forbidden lines depopulating the metastable even levels belonging to the 3dk and 3dk-14s configurations in Sc III (k = 1), Ti III (k = 2), V III (k = 3), Cr III (k = 4), Mn III (k = 5), Fe III (k = 6), Co III (k = 7), and Ni III (k = 8).

  5. Line Shapes and Intensities of Carbon Monoxide Transitions in the (3→0) and (4→1) Bands

    NASA Astrophysics Data System (ADS)

    Reed, Zachary; Polyansky, Oleg; Hodges, Joseph T.

    2017-06-01

    We have measured several carbon monoxide transitions in the (3→0) and (4→1) band using frequency stabilized cavity ringdown spectroscopy (FS-CRDS). The measured transitions are compared to the line strength values in HITRAN 2012 [1], those determined by Wojtewitz et al [2], and to theoretical calculations. The cavity length is actively locked to an iodine stabilized HeNe laser, providing long term frequency stability of 10 kHz and is linked to a self-referenced, octave-spanning frequency comb. The temperature of the optical cavity is actively regulated at the mK level, and the pressure measurements are SI-traceable. The sample is a NIST calibrated reference mixture of 11.98575(95)% CO in N_{2}. The absorption spectra are modeled using the Hartmann-Tran profile (HTP). The SNR in these spectra may exceed 10,000:1, which necessitates including the effects of speed dependence, collisional narrowing, and correlation between velocity-changing and dephasing collisions. The relative uncertainties of the line strengths calculated in this study are better than 0.1%. There are systematic differences on the 1% level for ^{12}CO against both HITRAN [1] and the previous work by Wojtewitz et al [2]. The measurement uncertainties are nearly an order of magnitude lower than previous results. Additionally, the relative uncertainties in the integrated areas of selected ^{12}CO and ^{13}CO transitions are less than 0.006% and 0.02%, respectively, providing an excellent test case for determination of isotope ratios by direct use of theoretical line intensity calculations. [1] Wojtewicz, S., et al., J Quant Spect and Rad Trans,2013. 130: p.191-200. [2]Rothman, L.S., et al., Journal of Quant Spect and Rad Trans, 2013. 130: p. 4-50.

  6. Kinetically forbidden transformations of water molecular assemblies in hydrophobic micropores.

    PubMed

    Ohba, Tomonori; Kaneko, Katsumi

    2011-06-21

    Water adsorption hysteresis is one of the most important phenomena observed during the interaction of water with hydrophobic surfaces. Adsorption hysteresis in micropores has strong relevance to the structure of adsorbed water. We used three typical models (cluster, monolayer, and uniform distribution structure models) to determine the structure of the water molecules adsorbed in hydrophobic slit-shaped carbon micropores. In each model, stabilization energy profiles were calculated for various fractional fillings by using the interaction potential theory. Simultaneously, molecular dynamics (MD) simulations of water adsorbed in the micropore of 1.1 nm pore width, which shows significant adsorption hysteresis, were performed to determine the kinetics of the observed structural transformations. The transformations between monolayer and cluster were slow, that is, kinetically forbidden at the fractional filling of 0.2 and 0.6, whereas the cluster-uniform distribution structure and uniform distribution structure-monolayer transformations were kinetically allowed. The kinetically forbidden transformation resulted in the occurrence of metastable structure of adsorbed water and was responsible for the observed adsorption hysteresis.

  7. Atomic data from the Iron Project. XVII. Radiative transition probabilities for dipole allowed and forbidden transitions in Fe III.

    NASA Astrophysics Data System (ADS)

    Nahar, S. N.; Pradhan, A. K.

    1996-11-01

    Transition probabilities are obtained for both the dipole allowed (E1) fine structure transitions and the forbidden electric quadrupole and magnetic dipole (E2, M1) transitions in Fe III. For the E1 transitions, ab initio calculations in the close coupling (CC) approximation using the R-matrix method are carried out in LS coupling with a 49-term eigenfunction expansion for Fe IV. The fine structure components are obtained through algebraic transformation of the LS line strengths, and the oscillator strengths and A-coefficients are computed using spectroscopic energies of the observed levels. Radiative transition probabilities for 9797 fine structure E1 transitions corresponding to 1408 LS multiplets among 200 bound states of Fe III are reported. Forbidden E2 and M1 transition probabilities are computed for 362 transitions among the 34 fine structure levels of all 16 LS terms dominated by the 3d^6^ configuration using optimised configuration-interaction wavefunctions from the SUPERSTRUCTURE program in the Breit-Pauli approximation. Comparison of the present results is made with previous calculations and significant differences are found. Theoretical line ratios computed using the present E2 and M1 A-coefficients show better agreement with observations for some prominent Fe III lines in the infra-red than those using the earlier data by Garstang (1957MNRAS.117..393G). This work is carried out as part of the Iron Project to obtain accurate radiative and collisional data for the Iron group elements.

  8. Electronic surveillance for healthcare-associated central line-associated bloodstream infections outside the intensive care unit.

    PubMed

    Woeltje, Keith F; McMullen, Kathleen M; Butler, Anne M; Goris, Ashleigh J; Doherty, Joshua A

    2011-11-01

    Manual surveillance for central line-associated bloodstream infections (CLABSIs) by infection prevention practitioners is time-consuming and often limited to intensive care units (ICUs). An automated surveillance system using existing databases with patient-level variables and microbiology data was investigated. Patients with a positive blood culture in 4 non-ICU wards at Barnes-Jewish Hospital between July 1, 2005, and December 31, 2006, were evaluated. CLABSI determination for these patients was made via 2 sources; a manual chart review and an automated review from electronically available data. Agreement between these 2 sources was used to develop the best-fit electronic algorithm that used a set of rules to identify a CLABSI. Sensitivity, specificity, predictive values, and Pearson's correlation were calculated for the various rule sets, using manual chart review as the reference standard. During the study period, 391 positive blood cultures from 331 patients were evaluated. Eighty-five (22%) of these were confirmed to be CLABSI by manual chart review. The best-fit model included presence of a catheter, blood culture positive for known pathogen or blood culture with a common skin contaminant confirmed by a second positive culture and the presence of fever, and no positive cultures with the same organism from another sterile site. The best-performing rule set had an overall sensitivity of 95.2%, specificity of 97.5%, positive predictive value of 90%, and negative predictive value of 99.2% compared with intensive manual surveillance. Although CLABSIs were slightly overpredicted by electronic surveillance compared with manual chart review, the method offers the possibility of performing acceptably good surveillance in areas where resources do not allow for traditional manual surveillance.

  9. Lines

    ERIC Educational Resources Information Center

    Mires, Peter B.

    2006-01-01

    National Geography Standards for the middle school years generally stress the teaching of latitude and longitude. There are many creative ways to explain the great grid that encircles our planet, but the author has found that students in his college-level geography courses especially enjoy human-interest stories associated with lines of latitude…

  10. Lines

    ERIC Educational Resources Information Center

    Mires, Peter B.

    2006-01-01

    National Geography Standards for the middle school years generally stress the teaching of latitude and longitude. There are many creative ways to explain the great grid that encircles our planet, but the author has found that students in his college-level geography courses especially enjoy human-interest stories associated with lines of latitude…

  11. Improving the output voltage waveform of an intense electron-beam accelerator based on helical type Blumlein pulse forming line

    NASA Astrophysics Data System (ADS)

    Cheng, Xin-Bing; Liu, Jin-Liang; Zhang, Hong-Bo; Feng, Jia-Huai; Qian, Bao-Liang

    2010-07-01

    The Blumlein pulse forming line (BPFL) consisting of an inner coaxial pulse forming line (PFL) and an outer coaxial PFL is widely used in the field of pulsed power, especially for intense electron-beam accelerators (IEBA). The output voltage waveform determines the quality and characteristics of the output beam current of the IEBA. Comparing with the conventional BPFL, an IEBA based on a helical type BPFL can increase the duration of the output voltage in the same geometrical volume. However, for the helical type BPFL, the voltage waveform on a matched load may be distorted which influences the electron-beam quality. In this paper, an IEBA based on helical type BPFL is studied theoretically. Based on telegrapher equations of the BPFL, a formula for the output voltage of IEBA is obtained when the transition section is taken into account, where the transition section is between the middle cylinder of BPFL and the load. From the theoretical analysis, it is found that the wave impedance and transit time of the transition section influence considerably the main pulse voltage waveform at the load, a step is formed in front of the main pulse, and a sharp spike is also formed at the end of the main pulse. In order to get a well-shaped square waveform at the load and to improve the electron-beam quality of such an accelerator, the wave impedance of the transition section should be equal to that of the inner PFL of helical type BPFL and the transit time of the transition section should be designed as short as possible. Experiments performed on an IEBA with the helical type BPFL show reasonable agreement with theoretical analysis.

  12. Qualitative tissue differentiation by analysing the intensity ratios of atomic emission lines using laser induced breakdown spectroscopy (LIBS): prospects for a feedback mechanism for surgical laser systems.

    PubMed

    Kanawade, Rajesh; Mahari, Fanuel; Klämpfl, Florian; Rohde, Maximilian; Knipfer, Christian; Tangermann-Gerk, Katja; Adler, Werner; Schmidt, Michael; Stelzle, Florian

    2015-01-01

    The research work presented in this paper focuses on qualitative tissue differentiation by monitoring the intensity ratios of atomic emissions using 'Laser Induced Breakdown Spectroscopy' (LIBS) on the plasma plume created during laser tissue ablation. The background of this study is to establish a real time feedback control mechanism for clinical laser surgery systems during the laser ablation process. Ex-vivo domestic pig tissue samples (muscle, fat, nerve and skin) were used in this experiment. Atomic emission intensity ratios were analyzed to find a characteristic spectral line for each tissue. The results showed characteristic elemental emission intensity ratios for the respective tissues. The spectral lines and intensity ratios of these specific elements varied among the different tissue types. The main goal of this study is to qualitatively and precisely identify different tissue types for tissue specific laser surgery. © 2015 The Authors. Journal of Biophotonics published by WILEY-VCH Verlag.

  13. On the chromatic number of a space with forbidden equilateral triangle

    SciTech Connect

    Zvonarev, A E; Raigorodskii, A M; Kharlamova, A A; Samirov, D V

    2014-09-30

    We improve the Frankl-Rödl estimate for the product of the numbers of edges in uniform hypergraphs with forbidden cardinalities of the intersection of edges. By using this estimate, we obtain explicit bounds for the chromatic number of a space with forbidden monochromatic equilateral triangles. Bibliography: 31 titles.

  14. Relative coronal abundances derived from X-ray observations 3: The effect of cascades on the relative intensity of Fe (XVII) line fluxes, and a revised iron abundance

    NASA Technical Reports Server (NTRS)

    Walker, A. B. C., Jr.; Rugge, H. R.; Weiss, K.

    1974-01-01

    Permitted lines in the optically thin coronal X-ray spectrum were analyzed to find the distribution of coronal material, as a function of temperature, without special assumptions concerning coronal conditions. The resonance lines of N, O, Ne, Na, Mg, Al, Si, S, and Ar which dominate the quiet coronal spectrum below 25A were observed. Coronal models were constructed and the relative abundances of these elements were determined. The intensity in the lines of the 2p-3d transitions near 15A was used in conjunction with these coronal models, with the assumption of coronal excitation, to determine the Fe XVII abundance. The relative intensities of the 2p-3d Fe XVII lines observed in the corona agreed with theoretical prediction. Using a more complete theoretical model, and higher resolution observations, a revised calculation of iron abundance relative to hydrogen of 0.000026 was made.

  15. X-ray diffraction patterns and diffracted intensity of Kα spectral lines of He-like ions

    NASA Astrophysics Data System (ADS)

    Goyal, Arun; Khatri, Indu; Singh, A. K.; Sharma, Rinku; Mohan, Man

    2017-09-01

    In the present paper, we have calculated fine-structure energy levels related to the configurations 1s2s, 1s2p, 1s3s and 1s3p by employing GRASP2K code. We have also computed radiative data for transitions from 1s2p 1 P1o, 1s2p 3 P2o, 1s2p 3 P1o and 1s2s 3S1 to the ground state 1s2. We have made comparisons of our presented energy levels and transition wavelengths with available results compiled by NIST and good agreement is achieved. We have also provided X-ray diffraction (XRD) patterns of Kα spectral lines, namely w, x, y and z of Cu XXVIII, Kr XXXV and Mo with diffraction angle and maximum diffracted intensity which is not published elsewhere in the literature. We believe that our presented results may be beneficial in determination of the order parameter, X-ray crystallography, solid-state drug analysis, forensic science, geological and medical applications.

  16. Implementing a multifaceted intervention to decrease central line-associated bloodstream infections in SEHA (Abu Dhabi Health Services Company) intensive care units: the Abu Dhabi experience.

    PubMed

    Latif, Asad; Kelly, Bernadette; Edrees, Hanan; Kent, Paula S; Weaver, Sallie J; Jovanovic, Branislava; Attallah, Hadeel; de Grouchy, Kristin K; Al-Obaidli, Ali; Goeschel, Christine A; Berenholtz, Sean M

    2015-07-01

    OBJECTIVE To determine whether implementation of a multifaceted intervention would significantly reduce the incidence of central line-associated bloodstream infections. DESIGN Prospective cohort collaborative. SETTING AND PARTICIPANTS Intensive care units of the Abu Dhabi Health Services Company hospitals in the Emirate of Abu Dhabi. INTERVENTIONS A bundled intervention consisting of 3 components was implemented as part of the program. It consisted of a multifaceted approach that targeted clinician use of evidence-based infection prevention recommendations, tools that supported the identification of local barriers to these practices, and implementation ideas to help ensure patients received the practices. Comprehensive unit-based safety teams were created to improve safety culture and teamwork. Finally, the measurement and feedback of monthly infection rate data to safety teams, senior leaders, and staff in participating intensive care units was encouraged. The main outcome measure was the quarterly rate of central line-associated bloodstream infections. RESULTS Eighteen intensive care units from 7 hospitals in Abu Dhabi implemented the program and achieved an overall 38% reduction in their central line-associated bloodstream infection rate, adjusted at the hospital and unit level. The number of units with a quarterly central line-associated bloodstream infection rate of less than 1 infection per 1,000 catheter-days increased by almost 40% between the baseline and postintervention periods. CONCLUSION A significant reduction in the global morbidity and mortality associated with central line-associated bloodstream infections is possible across intensive care units in disparate settings using a multifaceted intervention.

  17. Forbidden unique beta-decays and neutrino mass

    NASA Astrophysics Data System (ADS)

    Dvornický, Rastislav; Šimkovic, Fedor

    2013-12-01

    The measurement of the electron spectrum in beta-decays provides a robust direct determination of the values of neutrino masses. The planned rhenium beta-decay experiment, called the "Microcalorimeter Arrays for a Rhenium Experiment" (MARE), might probe the absolute mass scale of neutrinos with the same sensitivity as the Karlsruhe tritium neutrino mass (KATRIN) experiment, which is expected to collect data in a near future. In this contribution we discuss the spectrum of emitted electrons close to the end point in the case of the first unique forbidden beta-decay of 79Se, 107Pd and 187Re. It is found that the p3/2-wave emission dominates over the s1/2-wave. It is shown that the Kurie plot near the end point is within a good accuracy linear in the limit of massless neutrinos like the Kurie plot of the superallowed beta-decay of 3H.

  18. LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Channeling of microwave radiation in a double line containing a plasma filament produced by intense femtosecond laser pulses in air

    NASA Astrophysics Data System (ADS)

    Bogatov, N. A.; Kuznetsov, A. I.; Smirnov, A. I.; Stepanov, A. N.

    2009-10-01

    The channeling of microwave radiation is demonstrated experimentally in a double line in which a plasma filament produced in air by intense femtosecond laser pulses serves as one of the conductors. It is shown that during the propagation of microwave radiation in this line, ultrashort pulses are formed, their duration monotonically decreasing with increasing the propagation length (down to the value comparable with the microwave field period). These effects can be used for diagnostics of plasma in a filament.

  19. Simultaneous analysis of the Ballik-Ramsay and Phillips systems of C{sub 2} and observation of forbidden transitions between singlet and triplet states

    SciTech Connect

    Chen, Wang; Kawaguchi, Kentarou; Tang, Jian; Bernath, Peter F.

    2015-02-14

    6229 lines of the Ballik-Ramsay system (b{sup 3}Σ{sub g}{sup −}–a{sup 3}Π{sub u}) and the Phillips system (A{sup 1}Π{sub u}–X{sup 1}Σ{sub g}{sup +}) of C{sub 2} up to v = 8 and J = 76, which were taken from the literature or assigned in the present work, were analyzed simultaneously by least-squares fitting with 82 Dunham-like molecular parameters and spin-orbit interaction constants between the b{sup 3}Σ{sub g}{sup −} and X{sup 1}Σ{sub g}{sup +} states with a standard deviation of 0.0037 cm{sup −1} for the whole data set. As a result of the deperturbation analysis, the spin-orbit interaction constant A{sub bX} was determined as 6.333(7) cm{sup −1} and the energy difference between the X{sup 1}Σ{sub g}{sup +} and a{sup 3}Π{sub u} states was determined as 720.008(2) cm{sup −1} for the potential minima or 613.650(3) cm{sup −1} for the v = 0 levels with Merer and Brown’s N{sup 2} Hamiltonian for {sup 3}Π states, which is about 3.3 cm{sup −1} larger than the previously determined value. Due to this sizable change, a new energy-level crossing was found at J = 2 for v = 3 (F{sub 1}) of b{sup 3}Σ{sub g}{sup −} state and v = 6 of X{sup 1}Σ{sub g}{sup +} state, where the strong interaction causes a nearly complete mixing of the wave functions of the b{sup 3}Σ{sub g}{sup −} and X{sup 1}Σ{sub g}{sup +} states and the forbidden transitions become observable. Using the predictions of our deperturbation analysis, we were able to identify 16 forbidden transitions between the singlet and triplet states at the predicted frequencies with the expected intensities, which verifies our value for the energy difference between the X{sup 1}Σ{sub g}{sup +} and a{sup 3}Π{sub u} states.

  20. Cost-effectiveness of a quality improvement programme to reduce central line-associated bloodstream infections in intensive care units in the USA

    PubMed Central

    Herzer, Kurt R; Niessen, Louis; Constenla, Dagna O; Ward, William J; Pronovost, Peter J

    2014-01-01

    Objective To assess the cost-effectiveness of a multifaceted quality improvement programme focused on reducing central line-associated bloodstream infections in intensive care units. Design Cost-effectiveness analysis using a decision tree model to compare programme to non-programme intensive care units. Setting USA. Population Adult patients in the intensive care unit. Costs Economic costs of the programme and of central line-associated bloodstream infections were estimated from the perspective of the hospital and presented in 2013 US dollars. Main outcome measures Central line-associated bloodstream infections prevented, deaths averted due to central line-associated bloodstream infections prevented, and incremental cost-effectiveness ratios. Probabilistic sensitivity analysis was performed. Results Compared with current practice, the programme is strongly dominant and reduces bloodstream infections and deaths at no additional cost. The probabilistic sensitivity analysis showed that there was an almost 80% probability that the programme reduces bloodstream infections and the infections’ economic costs to hospitals. The opportunity cost of a bloodstream infection to a hospital was the most important model parameter in these analyses. Conclusions This multifaceted quality improvement programme, as it is currently implemented by hospitals on an increasingly large scale in the USA, likely reduces the economic costs of central line-associated bloodstream infections for US hospitals. Awareness among hospitals about the programme's benefits should enhance implementation. The programme's implementation has the potential to substantially reduce morbidity, mortality and economic costs associated with central line-associated bloodstream infections. PMID:25256190

  1. DISCOVERY OF TIME VARIATION OF THE INTENSITY OF MOLECULAR LINES IN IRC+10216 IN THE SUBMILLIMETER AND FAR-INFRARED DOMAINS

    SciTech Connect

    Cernicharo, J.; Quintana-Lacaci, G.; Agúndez, M.; Velilla-Prieto, L.; Daniel, F.; Decin, L.; Guélin, M.; Encrenaz, P.; De Beck, E.; Barlow, M. J.; Groenewegen, M. A. T.; Neufeld, D.; Pearson, J.

    2014-11-20

    We report on the discovery of strong intensity variations in the high rotational lines of abundant molecular species toward the archetypical circumstellar envelope of IRC+10216. The observations have been carried out with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument on board Herschel and with the IRAM30 m telescope. They cover several observing periods spreading over three years. The line intensity variations for molecules produced in the external layers of the envelope most likely result from time variations in the infrared pumping rates. We analyze the main implications this discovery has on the interpretation of molecular line emission in the envelopes of Mira-type stars. Radiative transfer calculations must take into account both the time variability of infrared pumping and the possible variation of the dust and gas temperatures with stellar phase in order to reproduce the observation of molecular lines at different epochs. The effect of gas temperature variations with stellar phase could be particularly important for lines produced in the innermost regions of the envelope. Each layer of the circumstellar envelope sees the stellar light radiation with a different lag time (phase). Our results show that this effect must be included in the models. The submillimeter and far infrared lines of asymptotic giant branch stars can no longer be considered as safe intensity calibrators.

  2. Discovery of Time Variation of the Intensity of Molecular Lines in IRC+10216 in the Submillimeter and Far-Infrared Domains

    NASA Astrophysics Data System (ADS)

    Cernicharo, J.; Teyssier, D.; Quintana-Lacaci, G.; Daniel, F.; Agúndez, M.; Velilla-Prieto, L.; Decin, L.; Guélin, M.; Encrenaz, P.; García-Lario, P.; de Beck, E.; Barlow, M. J.; Groenewegen, M. A. T.; Neufeld, D.; Pearson, J.

    2014-11-01

    We report on the discovery of strong intensity variations in the high rotational lines of abundant molecular species toward the archetypical circumstellar envelope of IRC+10216. The observations have been carried out with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument on board Herschel and with the IRAM30 m telescope. They cover several observing periods spreading over three years. The line intensity variations for molecules produced in the external layers of the envelope most likely result from time variations in the infrared pumping rates. We analyze the main implications this discovery has on the interpretation of molecular line emission in the envelopes of Mira-type stars. Radiative transfer calculations must take into account both the time variability of infrared pumping and the possible variation of the dust and gas temperatures with stellar phase in order to reproduce the observation of molecular lines at different epochs. The effect of gas temperature variations with stellar phase could be particularly important for lines produced in the innermost regions of the envelope. Each layer of the circumstellar envelope sees the stellar light radiation with a different lag time (phase). Our results show that this effect must be included in the models. The submillimeter and far infrared lines of asymptotic giant branch stars can no longer be considered as safe intensity calibrators.

  3. Effect of a vascular access team on central line-associated bloodstream infections in infants admitted to a neonatal intensive care unit: a systematic review.

    PubMed

    Legemaat, Monique M; Jongerden, Irene P; van Rens, Roland M F P T; Zielman, Marjanne; van den Hoogen, Agnes

    2015-05-01

    To review the effect of a vascular access team on the incidence of central line-associated bloodstream infections in infants admitted to a neonatal intensive care unit. MEDLINE, CINAHL, Embase, Web-of-Science and the Cochrane Library were searched until December 2013. Studies that evaluated the implementation of a vascular access team, and focused on the incidence of central line-associated bloodstream infections in infants admitted to a neonatal intensive care unit, were selected. Incidence rates of central line-associated bloodstream infections were extracted, as well as information on vascular access team tasks and team composition. The quality of studies was critically appraised using the McMaster tool for quantitative studies. Seven studies involving 136 to 414 participants were included. In general, the implementation of a vascular access team coincided with the implementation of concurrent interventions. All vascular access teams included nurses, and occasionally included physicians. Main tasks included insertion and maintenance of central lines. In all studies, a relative decrease of 45-79% in central line-associated bloodstream infections was reported. A vascular access team is a promising intervention to decrease central line-associated bloodstream infections in infants admitted to a neonatal intensive care unit. However, level of evidence for effectiveness is low. Future research is required to improve the strength of evidence for vascular access teams. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Far-ultraviolet MAMA detector imagery and emission-line CCD imagery of NGC 6240

    NASA Technical Reports Server (NTRS)

    Smith, Andrew M.; Hill, Robert S.; Vrba, Frederick J.; Timothy, J. G.

    1992-01-01

    An image of the luminous infrared galaxy NGC 6240 at 1480 A was obtained using a multianode microchannel array (MAMA) detector with a rocket-borne telescope. At distances greater than 12 arcsec from the nucleus, the measured ultraviolet luminosity implies intensive star formation activity equal to 2-3 times that of a spiral galaxy such as M83. Optical images in the H-beta and forbidden O III 5007 A emission lines reveal a region of high excitation east of the nucleus between the centers of disks 1 and 2 as described by Bland-Hawthorn et al.

  5. Far-ultraviolet MAMA detector imagery and emission-line CCD imagery of NGC 6240

    NASA Technical Reports Server (NTRS)

    Smith, Andrew M.; Hill, Robert S.; Vrba, Frederick J.; Timothy, J. G.

    1992-01-01

    An image of the luminous infrared galaxy NGC 6240 at 1480 A was obtained using a multianode microchannel array (MAMA) detector with a rocket-borne telescope. At distances greater than 12 arcsec from the nucleus, the measured ultraviolet luminosity implies intensive star formation activity equal to 2-3 times that of a spiral galaxy such as M83. Optical images in the H-beta and forbidden O III 5007 A emission lines reveal a region of high excitation east of the nucleus between the centers of disks 1 and 2 as described by Bland-Hawthorn et al.

  6. Homogeneous and inhomogeneous broadenings and the Voigt line shapes in the phase-resolved and intensity sum-frequency generation vibrational spectroscopy.

    PubMed

    Chen, Shun-Li; Fu, Li; Gan, Wei; Wang, Hong-Fei

    2016-01-21

    In this report, we show that the ability to measure the sub-1 cm(-1) resolution phase-resolved and intensity high-resolution broadband sum frequency generation vibrational spectra of the -CN stretch vibration of the Langmuir-Blodgett (LB) monolayer of the 4-n-octyl-4'-cyanobiphenyl (8CB) on the z-cut α-quartz surface allows the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral line shapes in detail. The difference of the full width at half maximum (FWHM) of the imaginary and intensity sum-frequency generation vibrational spectroscopy spectra of the same vibrational mode is the signature of the Voigt line shape and it measures the relative contribution to the overall line shape from the homogeneous and inhomogeneous broadenings in SFG vibrational spectra. From the phase-resolved and intensity spectra, we found that the FWHM of the 2238.00 ± 0.02 cm(-1) peak in the phase-resolved imaginary and intensity spectra is 19.2 ± 0.2 cm(-1) and 21.6 ± 0.4 cm(-1), respectively, for the -CN group of the 8CB LB monolayer on the z-cut α-quartz crystal surface. The FWHM width difference of 2.4 cm(-1) agrees quantitatively with a Voigt line shape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm(-1) and an inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm(-1). These results shed new lights on the understanding and interpretation of the line shapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general.

  7. Determination of Electronic Temperature and Density in Narrow Line Regions

    NASA Astrophysics Data System (ADS)

    Quintero, S.; Higuera-G., Mario A.

    2017-07-01

    We use observations of forbidden emission lines: [SII], [OII], N[II] and [OIII] from a sample of objects located in the Sloan Digital Sky Survey (SDSS) and determined the electronic temperature and densities.

  8. Surveillance Length and Validity of Benchmarks for Central Line-Associated Bloodstream Infection Incidence Rates in Intensive Care Units

    PubMed Central

    Fontela, Patricia S.; Quach, Caroline; Buckeridge, David; Pai, Madukhar; Platt, Robert W.

    2012-01-01

    Introduction Several national and regional central line-associated bloodstream infections (CLABSI) surveillance programs do not require continuous hospital participation. We evaluated the effect of different hospital participation requirements on the validity of annual CLABSI incidence rate benchmarks for intensive care units (ICUs). Methods We estimated the annual pooled CLABSI incidence rates for both a real regional (<100 ICUs) and a simulated national (600 ICUs) surveillance program, which were used as a reference for the simulations. We simulated scenarios where the annual surveillance participation was randomly or non-randomly reduced. Each scenario's annual pooled CLABSI incidence rate was estimated and compared to the reference rates in terms of validity, bias, and proportion of simulation iterations that presented valid estimates (ideal if≥90%). Results All random scenarios generated valid CLABSI incidence rates estimates (bias −0.37 to 0.07 CLABSI/1000 CVC-days), while non-random scenarios presented a wide range of valid estimates (0 to 100%) and higher bias (−2.18 to 1.27 CLABSI/1000 CVC-days). In random scenarios, the higher the number of participating ICUs, the shorter the participation required to generate ≥90% valid replicates. While participation requirements in a countrywide program ranged from 3 to 13 surveillance blocks (1 block = 28 days), requirements for a regional program ranged from 9 to 13 blocks. Conclusions Based on the results of our model of national CLABSI reporting, the shortening of participation requirements may be suitable for nationwide ICU CLABSI surveillance programs if participation months are randomly chosen. However, our regional models showed that regional programs should opt for continuous participation to avoid biased benchmarks. PMID:22586480

  9. Investigation of effective line intensities of trans-HONO near 1255 cm-1 using continuous-wave quantum cascade laser spectrometers

    NASA Astrophysics Data System (ADS)

    Cui, Xiaojuan; Dong, Fengzhong; Sigrist, Markus W.; Zhang, Zhirong; Wu, Bian; Xia, Hua; Pang, Tao; Sun, Pengshuai; Fertein, Eric; Chen, Weidong

    2016-10-01

    Effective line intensities of P branch transitions of trans-nitrous acid (HONO) in the ν3 H-O-N bending mode near 1255 cm-1 have been determined by scaling measured HONO absorption intensities by continuous-wave quantum cascade laser absorption spectroscopy to reference values. Gaseous HONO samples were synthetized in the laboratory using the reaction of H2SO4 and NaNO2 solutions and the heterogeneous formation on surfaces in the presence of ambient water vapor and NO2 gas in a sealed gas sampling bag. The quantification of HONO was performed using a denuder associated with a NOx analyzer. Observed absorption line strengths for the trans conformer are found to be by a factor of approximately 1.17 higher than previously reported line strengths.

  10. An optical emission-line phase of the extreme carbon star IRC +30219

    NASA Technical Reports Server (NTRS)

    Cohen, M.

    1980-01-01

    Optical spectroscopic monitoring of the extreme carbon star IRC +30219 has revealed striking changes between 1977 and 1980. The stellar photosphere was barely visible in early 1979. There was an emission line spectrum consisting of H, forbidden O I, forbidden O II, forbidden N I, forbidden N II, forbidden S II, and He I. It is likely that these lines arose in a shocked region where recent stellar mass loss encountered the extensive circumstellar envelope. By late 1979, this emission-line spectrum had vanished, and the photosphere had reappeared. The weakening of the photospheric features in early 1979 was caused by increased attenuation of starlight and overlying thermal emission, both due to recently condensed hot dust grains.

  11. Influence of the operating parameters and of the sample introduction system on time correlation of line intensities using an axially viewed CCD-based ICP-AES system

    NASA Astrophysics Data System (ADS)

    Grotti, Marco; Todolí, José Luis; Mermet, Jean Michel

    2010-02-01

    The influence of the acquisition and operating parameters on time correlation between emission line intensities was investigated using axially viewed inductively coupled plasma-multichannel-based emission spectrometry and various sample introduction systems. It was found that to obtain flicker-noise limited signals, necessary to compensate for time-correlated signal fluctuations by internal standardization, the flicker-noise magnitude of the sample introduction system, the integration time and the emission line intensity had to be considered. The highest correlation between lines was observed for ultrasonic nebulization with desolvatation, the noisiest system among those considered, for which the contribution of the uncorrelated shot-noise was negligible. In contrast, for sample introduction systems characterized by lower flicker-noise levels, shot-noise led to high, non-correlated RSD values, making the internal standard method to be much less efficient. To minimize shot-noise, time correlation was improved by increasing the emission line intensities and the integration time. Improvement in repeatability did not depend only on time correlation, but also on the ratio between the relative standard deviations of the analytical and reference lines. The best signal compensation was obtained when RSD values of the reference and analytical lines were similar, which is usually obtained when the system is flicker-noise limited, while departure from similarity can lead to a degradation of repeatability when using the internal standard method. Moreover, the use of so-called robust plasma conditions, i.e. a high power (1500 W) along with a low carrier gas flow rate (0.8 L/min) improved also the compensation. Finally, high correlation and consequent improvement in repeatability by internal standardization was observed also in the presence of complex matrices (sediment and soil samples), although a matrix-induced degradation of the correlation between lines was generally

  12. Analysis of the ν 8+ ν 9Band of HNO 3, Line Positions and Intensities, and Resonances Involving the v6= v7= 1 Dark State

    NASA Astrophysics Data System (ADS)

    Perrin, A.; Flaud, J.-M.; Keller, F.; Goldman, A.; Blatherwick, R. D.; Murcray, F. J.; Rinsland, C. P.

    1999-03-01

    Using a high-resolution (R= 0.0025 cm-1) Fourier transform spectrum of nitric acid recorded at room temperature in the 1100-1240 cm-1region, it has been possible to perform a more extended analysis of the ν8+ ν9band of HNO3centered at 1205.7075 cm-1. As in a recent analysis of this band [W. F. Wang, P. P. Ong, T. L. Tan, E. C. Looi, and H. H. Teo,J. Mol. Spectrosc.183, 407-413 (1997)], the Hamiltonian used for the line positions calculation takes into account, for the upper state, the ΔK= ±2 anharmonic resonance linking the rotational levels of thev8=v9= 1 "bright" vibrational state and those of the "dark"v6=v7= 1 vibrational state. More than 4800 lines were assigned in the ν8+ ν9band, which involve significantly higher rotational quantum numbers than in previous works. On the other hand, and surprisingly as compared to previous studies, the ν8+ ν9band appears to be a hybrid band. In fact, nonnegligibleB-type transitions could be clearly identified among the much strongerA-type lines. Accordingly, a set of individual line intensities were measured for lines of both types and were introduced in a least-squares fit to get theA- andB-type components of the transition moment operator. Finally, a synthetic spectrum of the 8.3-μm region of HNO3has been generated, using for the line positions and line intensities the Hamiltonian constants and the expansion of the transition moment operator which were determined in this work. In this way, theB-type and theA-type components of the ν8+ ν9band appear to contribute for about {1}/{4} and {3}/{4}, respectively, to the total band intensity.

  13. Dynamic Stark effect and forbidden-transition spectrallineshapes

    SciTech Connect

    Stalnaker, Jason E.; Budker, D.; Freedman, S.J.; Guzman, J.S.; Rochester, S.M.; Yashchuk, V.V.

    2005-12-15

    We report on an experimental and theoretical study of thedynamic (ac) Stark effect on a for bidden transition. A general frameworkfor parameterizing and describing off-resonant ac-Stark shifts ispresented. A model is developed to calculate spectral line shapesresulting from resonant excitation of atoms in an intense standinglight-wave in the presence of off-resonant ac-Stark shifts. The model isused in the analysis and interpretation of a measurement of the ac-Starkshifts of the static-electric-field-induced 6s2 1S0 -->5d6s 3D1transition at 408 nm in atomic Yb. The results are in agreement withestimates of the ac-Stark shift of the transition under the assumptionthat the shift is dominated by that of the 6s2 1S0 ground state. Adetailed description of the experiment and analysis is presented. Abi-product of this work is an ind ependent determination (from thesaturation behavior of the 408-nm transition) of the Stark transitionpolarizability, which is found to be in agreement with our earliermeasurement. This work is part of the ongoing effort aimed at a precisionmeasurement of atomic parity-violation effects in Yb.

  14. Excitation of oxygen permitted line emissions in the tropical nightglow.

    NASA Technical Reports Server (NTRS)

    Tinsley, B. A.; Christensen, A. B.; Bittencourt, J.; Gouveia, H.; Angreji, P. D.; Takahashi, H.

    1973-01-01

    The ultraviolet oxygen emissions at 1304 and 1356 A in the tropical nightglow seen from Ogo 4 by Hicks and Chubb (1970) and Barth and Schaffner (1970) are accompanied by emission at 7774 and 4368 A, which have been studied from the ground by looking through the beam of an ionosonde operated under the Appleton anomaly ionization peaks. Simultaneous forbidden O I 6300-A measurements were also made. A theoretical value for the partial rate coefficient for 7774 emission by radiative recombination has been obtained, and from the ionospheric data and a model atmosphere the expected rates of radiative recombination and ion-ion recombination were calculated. The time variations and absolute intensity of the calculated and observed intensities agree reasonably well, when the uncertainties involved are considered. It is concluded that radiative recombination is the major source of the tropical oxygen permitted line emissions, accompanied by a small contribution from ion-ion recombination.

  15. Forbidden unique beta-decays and neutrino mass

    SciTech Connect

    Dvornický, Rastislav; Šimkovic, Fedor

    2013-12-30

    The measurement of the electron spectrum in beta-decays provides a robust direct determination of the values of neutrino masses. The planned rhenium beta-decay experiment, called the “Microcalorimeter Arrays for a Rhenium Experiment” (MARE), might probe the absolute mass scale of neutrinos with the same sensitivity as the Karlsruhe tritium neutrino mass (KATRIN) experiment, which is expected to collect data in a near future. In this contribution we discuss the spectrum of emitted electrons close to the end point in the case of the first unique forbidden beta-decay of {sup 79}Se, {sup 107}Pd and {sup 187}Re. It is found that the p{sub 3/2}-wave emission dominates over the s{sub 1/2}-wave. It is shown that the Kurie plot near the end point is within a good accuracy linear in the limit of massless neutrinos like the Kurie plot of the superallowed beta-decay of {sup 3}H.

  16. Searches for Rare or Forbidden Semileptonic Charm Decays

    SciTech Connect

    Lees, J.P.

    2011-08-15

    We present searches for rare or forbidden charm decays of the form X{sub c}{sup +} {yields} h{sup {+-}}{ell}{sup {-+}}{ell}{sup ({prime})+}, where X{sub c}{sup +} is a charm hardron (D{sup +}, D{sub s}{sup +}, or {Lambda}{sub c}{sup +}), h{sup {+-}} is a pion, kaon, or proton, and {ell}{sup ({prime}){+-}} is an electron or muon. The analysis is based on 384 fb{sup -1} of e{sup +}e{sup -} annihilation data collected at or close to the {Upsilon}(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10{sup -6} and 44 x 10{sup -6} depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.

  17. miRNA-Mediated Relationships between Cis-SNP Genotypes and Transcript Intensities in Lymphocyte Cell Lines

    PubMed Central

    Zhang, Wensheng; Edwards, Andrea; Zhu, Dongxiao; Flemington, Erik K.; Deininger, Prescott; Zhang, Kun

    2012-01-01

    In metazoans, miRNAs regulate gene expression primarily through binding to target sites in the 3′ UTRs (untranslated regions) of messenger RNAs (mRNAs). Cis-acting variants within, or close to, a gene are crucial in explaining the variability of gene expression measures. Single nucleotide polymorphisms (SNPs) in the 3′ UTRs of genes can affect the base-pairing between miRNAs and mRNAs, and hence disrupt existing target sites (in the reference sequence) or create novel target sites, suggesting a possible mechanism for cis regulation of gene expression. Moreover, because the alleles of different SNPs within a DNA sequence of limited length tend to be in strong linkage disequilibrium (LD), we hypothesize the variants of miRNA target sites caused by SNPs potentially function as bridges linking the documented cis-SNP markers to the expression of the associated genes. A large-scale analysis was herein performed to test this hypothesis. By systematically integrating multiple latest information sources, we found 21 significant gene-level SNP-involved miRNA-mediated post-transcriptional regulation modules (SNP-MPRMs) in the form of SNP-miRNA-mRNA triplets in lymphocyte cell lines for the CEU and YRI populations. Among the cognate genes, six including ALG8, DGKE, GNA12, KLF11, LRPAP1, and MMAB are related to multiple genetic diseases such as depressive disorder and Type-II diabetes. Furthermore, we found that ∼35% of the documented transcript intensity-related cis-SNPs (∼950) in a recent publication are identical to, or in significant linkage disequilibrium (LD) (p<0.01) with, one or multiple SNPs located in miRNA target sites. Based on these associations (or identities), 69 significant exon-level SNP-MPRMs and 12 disease genes were further determined for two populations. These results provide concrete in silico evidence for the proposed hypothesis. The discovered modules warrant additional follow-up in independent laboratory studies. PMID:22348086

  18. Measurements of Line Positions and Intensities of 14NH_3 in the 1.5 μm Region

    NASA Astrophysics Data System (ADS)

    Sung, Keeyoon; Brown, Linda R.; Huang, Xinchuan; Schwenke, David W.; Lee, Timothy J.

    2011-06-01

    In the atmosphere of outer planets, low mass brown dwarfs, and possibly extrasolar planets, ammonia (NH_3) is one of the major opacity sources particularly in the 1.5 μm region (the H-band). However, the spectroscopic information of NH_3 in the region is completely missing in the HITRAN database. NH_3 has four infrared active fundamental modes, with the well-known inversion doubling for {ν_2} band, in addition to the usual vibrational degeneracies. Its strong bands, {ν_1}, {ν_3} and 2{ν_4}, dominate the spectrum at 3 μm, while their corresponding overtone and combination bands (e.g., 2{ν_1}, 2{ν_3}, {ν_1}+{ν_3}, {ν_1}+2{ν_4} and {ν_3}+2{ν_4}) are prominent in the 1.5 μm region. As part of an effort to provide a complete set of NH_3 spectroscopic information in the 1.5 μm region, we are analyzing the laboratory spectra recorded at various temperatures (200 - 299 K) with the McMath-Pierce Fourier transform spectrometer (FTS) on Kitt Peak Observatory in Arizona. Line positions and strengths have been measured from the laboratory spectra, from which lower state energies and quantum assignments are being determined by adopting intensity ratios at two different temperatures and combination differnces. A theoretical IR linelist built upon the recent HSL-2 potential energy surface (nonadiabatic corrections included) is complementarily used for the quantum assignments. Preliminary results are presented for {ν_1}+{ν_3}, 2{ν_3}, {ν_1}+2{ν_4} and {ν_3}+{2ν_4} bands and compared with those from early work available. X. Huang, D.W. Schwenke, and T.J. Lee J. Chem. Phys. 134, (2011) 044320/044321 The research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology and the Ames Research Center under contracts with National Aeronautics and Space Administration.

  19. The on-line each hour and each minute automatically correction data of total NM intensity and different multiplicities on snow effect

    NASA Astrophysics Data System (ADS)

    Lev, Dorman; Zukerman, Igor; Pustilnik, Lev; Dai, Uri; Shternlib, Abracham; Shai Applbaum, David; Kazantsev, Vasilii; Kozliner, Lev; Ben Israel, Isaac

    In our report Dorman et al. “Snow effect for total NM intensity and different multiplicities on Mt. Hermon during 1998 - 2014”, we described the method to determine the snow effect in the total NM intensity and different multiplicities. By using regression coefficients obtained for the long period of observations, obtained in this paper, we developed method of automatically correction on-line each hour and each minute data of total NM intensity and different multiplicities on snow effect. We show that expected average errors in this method for one hour observation is about 0.2%, what is comparable with the statistical error. We show also how to correct on-line automatically one-minute data on snow effect. Corrected on-line one minute data can be now used for the forecasting of great radiation hazards from solar flares and estimation of expected total fluency and radiation hazards for satellites electronics and astronauts health, as well as for people and electronics on regular airlines at altitudes about 10 km. Corrected on-line one hour data can be now used for the forecasting of great magnetic storms, dangerous for satellites, technologies, and people health. https://www.cospar-assembly.org/user/download2.php?id=29566&type=preview

  20. Beta spectrum of unique first-forbidden decays as a novel test for fundamental symmetries

    NASA Astrophysics Data System (ADS)

    Glick-Magid, Ayala; Mishnayot, Yonatan; Mukul, Ish; Hass, Michael; Vaintraub, Sergey; Ron, Guy; Gazit, Doron

    2017-04-01

    Within the Standard Model, the weak interaction of quarks and leptons is characterized by certain symmetry properties, such as maximal breaking of parity and favored helicity. These are related to the V - A structure of the weak interaction. These characteristics were discovered by studying correlations in the directions of the outgoing leptons in nuclear beta decays. Presently, correlation measurements in nuclear beta decays are intensively studied to probe for signatures for deviations from these couplings, which are an indication of Beyond Standard Model physics. We show that the structure of the energy spectrum of emitted electrons in unique first-forbidden β-decays is sensitive to the symmetries of the weak interaction, and thus can be used as a novel probe of physics beyond the standard model. Furthermore, the energy spectrum gives constraints both in the case of right and left couplings of the new beyond standard model currents. We show that a measurement with modest energy resolution of ≈ 20 keV is expected to lead to new constraints on beyond the standard model interactions with tensor couplings.

  1. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Implications for Spectral Line Intensity Mapping at Millimeter Wavelengths and CMB Spectral Distortions

    NASA Astrophysics Data System (ADS)

    Carilli, C. L.; Chluba, J.; Decarli, R.; Walter, F.; Aravena, M.; Wagg, J.; Popping, G.; Cortes, P.; Hodge, J.; Weiss, A.; Bertoldi, F.; Riechers, D.

    2016-12-01

    We present direct estimates of the mean sky brightness temperature in observing bands around 99 and 242 GHz due to line emission from distant galaxies. These values are calculated from the summed line emission observed in a blind, deep survey for spectral line emission from high redshift galaxies using ALMA (the ALMA spectral deep field observations “ASPECS” survey). In the 99 GHz band, the mean brightness will be dominated by rotational transitions of CO from intermediate and high redshift galaxies. In the 242 GHz band, the emission could be a combination of higher order CO lines, and possibly [C ii] 158 μm line emission from very high redshift galaxies (z ˜ 6-7). The mean line surface brightness is a quantity that is relevant to measurements of spectral distortions of the cosmic microwave background, and as a potential tool for studying large-scale structures in the early universe using intensity mapping. While the cosmic volume and the number of detections are admittedly small, this pilot survey provides a direct measure of the mean line surface brightness, independent of conversion factors, excitation, or other galaxy formation model assumptions. The mean surface brightness in the 99 GHZ band is: T B = 0.94 ± 0.09 μK. In the 242 GHz band, the mean brightness is: T B = 0.55 ± 0.033 μK. These should be interpreted as lower limits on the average sky signal, since we only include lines detected individually in the blind survey, while in a low resolution intensity mapping experiment, there will also be the summed contribution from lower luminosity galaxies that cannot be detected individually in the current blind survey.

  2. Anti-screening optically allowed and forbidden collisional excitations in nonthermal astrophysical plasmas

    SciTech Connect

    Hong, Woo-Pyo; Jung, Young-Dae

    2014-08-01

    The influence of nonthermal shielding on the optically allowed and forbidden anti-screening channels for ion-ion collisional excitations is investigated in astrophysical Lorentzian plasmas. The semiclassical trajectory method and effective interaction Hamiltonian are employed to obtain the transition amplitudes, differential cross-sections, and momentum transfer-dependent effective projectile charges for the optically allowed and forbidden excitation channels as functions of the impact parameter, collision energy, Debye radius, and spectral index of nonthermal astrophysical plasmas. It is found that the nonthermal effect suppresses the ion-ion collisional excitation probability in astrophysical Lorentzian plasmas. Additionally, the influence of nonthermal shielding on the optically allowed transition is found to be more significant than that on the optically forbidden transition. The variations of the nonthermal shielding effects on the optically allowed and forbidden anti-screening channels in astrophysical nonthermal plasmas are also discussed.

  3. Permitted and forbidden sets in discrete-time linear threshold recurrent neural networks.

    PubMed

    Yi, Zhang; Zhang, Lei; Yu, Jiali; Tan, Kok Kiong

    2009-06-01

    The concepts of permitted and forbidden sets enable a new perspective of the memory in neural networks. Such concepts exhibit interesting dynamics in recurrent neural networks. This paper studies the basic theories of permitted and forbidden sets of the linear threshold discrete-time recurrent neural networks. The linear threshold transfer function has been regarded as an adequate transfer function for recurrent neural networks. Networks with this transfer function form a class of hybrid analog and digital networks which are especially useful for perceptual computations. Networks in discrete time can directly provide algorithms for efficient implementation in digital hardware. The main contribution of this paper is to establish foundations of permitted and forbidden sets. Necessary and sufficient conditions for the linear threshold discrete-time recurrent neural networks are obtained for complete convergence, existence of permitted and forbidden sets, as well as conditionally multiattractivity, respectively. Simulation studies explore some possible interesting practical applications.

  4. What are the intensities and line-shapes of the twenty four polarization terms in coherent anti-Stokes Raman spectroscopy?

    NASA Astrophysics Data System (ADS)

    Niu, Kai; Lee, Soo-Y.

    2015-12-01

    Coherent anti-Stokes Raman spectroscopy (CARS) is conventionally described by just one diagram/term where the three electric field interactions act on the ket side in a Feynman dual time-line diagram in a specific time order of pump, Stokes and probe pulses. In theory, however, any third-order nonlinear spectroscopy with three different electric fields interacting with a molecule can be described by forty eight diagrams/terms. They reduce to just 24 diagrams/terms if we treat the time ordering of the electric field interactions on the ket independently of those on the bra, i.e. the ket and bra wave packets evolve independently. The twenty four polarization terms can be calculated in the multidimensional, separable harmonic oscillator model to obtain the intensities and line-shapes. It is shown that in fs/ps CARS, for the two cases of off-resonance CARS in toluene and resonance CARS in rhodamine 6G, where we use a fs pump pulse, a fs Stokes pulse and a ps probe pulse, we obtain sharp vibrational lines in four of the polarization terms where the pump and Stokes pulses can create a vibrational coherence on the ground electronic state, while the spectral line-shapes of the other twenty terms are broad and featureless. The conventional CARS term with sharp vibrational lines is the dominant term, with intensity at least one order of magnitude larger than the other terms.

  5. What are the intensities and line-shapes of the twenty four polarization terms in coherent anti-Stokes Raman spectroscopy?

    SciTech Connect

    Niu, Kai; Lee, Soo-Y.

    2015-12-15

    Coherent anti-Stokes Raman spectroscopy (CARS) is conventionally described by just one diagram/term where the three electric field interactions act on the ket side in a Feynman dual time-line diagram in a specific time order of pump, Stokes and probe pulses. In theory, however, any third-order nonlinear spectroscopy with three different electric fields interacting with a molecule can be described by forty eight diagrams/terms. They reduce to just 24 diagrams/terms if we treat the time ordering of the electric field interactions on the ket independently of those on the bra, i.e. the ket and bra wave packets evolve independently. The twenty four polarization terms can be calculated in the multidimensional, separable harmonic oscillator model to obtain the intensities and line-shapes. It is shown that in fs/ps CARS, for the two cases of off-resonance CARS in toluene and resonance CARS in rhodamine 6G, where we use a fs pump pulse, a fs Stokes pulse and a ps probe pulse, we obtain sharp vibrational lines in four of the polarization terms where the pump and Stokes pulses can create a vibrational coherence on the ground electronic state, while the spectral line-shapes of the other twenty terms are broad and featureless. The conventional CARS term with sharp vibrational lines is the dominant term, with intensity at least one order of magnitude larger than the other terms.

  6. The Role of Velocity Redistribution in Enhancing the Intensity of the He II 304 A Line in the Quiet Sun Spectrum

    NASA Technical Reports Server (NTRS)

    Andretta, Vincenzo; Jordan, Stuart D.; Brosius, Jeffrey W.; Davila, Joseph M.; Thomas, Roger J.; Behring, William E.; Thompson, William T.; Garcia, Adriana

    1999-01-01

    We present observational evidence of the effect of small scale ("microturbulent") velocities in enhancing the intensity of the He II lambda304 line with respect to other transition region emission lines, a process we call "velocity redistribution". We first show results from the 1991 and 1993 flights of SERTS (Solar EUV Rocket Telescope and Spectrograph). The spectral resolution of the SERTS instrument was sufficient to infer that, at the spatial resolution of 5", the line profile is nearly gaussian both in the quiet Sun and in active regions. We were then able to determine, for the quiet Sun, a lower limit for the amplitude of non-thermal motions in the region of formation of the 304 A line of the order of 10 km/s. We estimated that, in the presence of the steep temperature gradients of the solar Transition Region (TR), velocities of this magnitude can significantly enhance the intensity of that line, thus at least helping to bridge the gap between calculated and observed values. We also estimated the functional dependence of such an enhancement on the relevant parameters (non-thermal velocities, temperature gradient, and pressure). We then present results from a coordinated campaign, using SOHO/CDS and H-alpha spectroheliograms from Coimbra Observatory, aimed at determining the relationship between regions of enhanced helium emission and chromospheric velocity fields and transition region emission in the quiescent atmosphere. Using these data, we examined the behavior of the He II lambda304 line in the quiet Sun supergranular network and compared it with other TR lines, in particular with O III lambda600. We also examined the association of 304 A emission with the so-called "coarse dark mottle", chromospheric structures seen in H-alpha red wing images and associated with spicules. We found that all these observations are consistent with the velocity redistribution picture.

  7. The solar XUV He I and He II emission lines. I - Intensities and gross center-to-limb behavior

    NASA Technical Reports Server (NTRS)

    Mango, S. A.; Bohlin, J. D.; Glackin, D. L.; Linsky, J. L.

    1978-01-01

    The center-to-limb variation of the He II 304- and 256-A lines and He I 584- and 537-A lines is derived for different solar features, but averaged over the chromospheric supergranulation structure. The general trend is for limb brightening in quiet-sun regions, limb neutrality in unipolar magnetic regions (UMR), and limb darkening in polar coronal holes. The center-to-limb behavior in these optically thick emission lines indicates collisional excitation and decreasing transition-region temperature gradients with respect to optical depth in the sequence quiet sun to UMR to coronal hole.

  8. The solar XUV He I and He II emission lines. I - Intensities and gross center-to-limb behavior

    NASA Technical Reports Server (NTRS)

    Mango, S. A.; Bohlin, J. D.; Glackin, D. L.; Linsky, J. L.

    1978-01-01

    The center-to-limb variation of the He II 304- and 256-A lines and He I 584- and 537-A lines is derived for different solar features, but averaged over the chromospheric supergranulation structure. The general trend is for limb brightening in quiet-sun regions, limb neutrality in unipolar magnetic regions (UMR), and limb darkening in polar coronal holes. The center-to-limb behavior in these optically thick emission lines indicates collisional excitation and decreasing transition-region temperature gradients with respect to optical depth in the sequence quiet sun to UMR to coronal hole.

  9. NON-EQUILIBRIUM MODELING OF THE FE XVII 3C/3D LINE RATIO IN AN INTENSE X-RAY FREE-ELECTRON LASER EXCITED PLASMA

    SciTech Connect

    Loch, S. D.; Ballance, C. P.; Li, Y.; Fogle, M.; Fontes, C. J.

    2015-03-01

    Recent measurements using an X-ray Free Electron Laser (XFEL) and an Electron Beam Ion Trap at the Linac Coherent Light Source facility highlighted large discrepancies between the observed and theoretical values for the Fe xvii 3C/3D line intensity ratio. This result raised the question of whether the theoretical oscillator strengths may be significantly in error, due to insufficiencies in the atomic structure calculations. We present time-dependent spectral modeling of this experiment and show that non-equilibrium effects can dramatically reduce the predicted 3C/3D line intensity ratio, compared with that obtained by simply taking the ratio of oscillator strengths. Once these non-equilibrium effects are accounted for, the measured line intensity ratio can be used to determine a revised value for the 3C/3D oscillator strength ratio, giving a range from 3.0 to 3.5. We also provide a framework to narrow this range further, if more precise information about the pulse parameters can be determined. We discuss the implications of the new results for the use of Fe xvii spectral features as astrophysical diagnostics and investigate the importance of time-dependent effects in interpreting XFEL-excited plasmas.

  10. Revealing discriminating power of the elements in edible sea salts: Line-intensity correlation analysis from laser-induced plasma emission spectra

    NASA Astrophysics Data System (ADS)

    Lee, Yonghoon; Ham, Kyung-Sik; Han, Song-Hee; Yoo, Jonghyun; Jeong, Sungho

    2014-11-01

    We have investigated the discriminating power of the elements in edible sea salts using Laser-Induced Breakdown Spectroscopy (LIBS). For the ten different sea salts from South Korea, China, Japan, France, Mexico and New Zealand, LIBS spectra were recorded in the spectral range between 190 and 1040 nm, identifying the presence of Na, Cl, K, Ca, Mg, Li, Sr, Al, Si, Ti, Fe, C, O, N, and H. Intensity correlation analysis of the observed emission lines provided a valuable insight into the discriminating power of the different elements in the sea salts. The correlation analysis suggests that the elements with independent discrimination power can be categorized into three groups; those that represent dissolved ions in seawater (K, Li, and Mg), those that are associated with calcified particles (Ca and Sr), and those that are present in soils contained in the sea salts (Al, Si, Ti, and Fe). Classification models using a few emission lines selected based on the results from intensity correlation analysis and full broadband LIBS spectra were developed based on Principal Component Analysis (PCA) and Partial Least Squares-Discriminant Analysis (PLS-DA) and their performances were compared. Our results indicate that effective combination of a few emission lines can provide a dependable model for discriminating the edible sea salts and the performance is not much degraded from that based on the full broadband spectra. This can be rationalized by the intensity correlation results.

  11. Differential electron scattering cross sections for the first optically forbidden and resonance transitions in Mg II, Zn II and Cd II

    NASA Technical Reports Server (NTRS)

    Williams, I. D.; Chutjian, A.; Mawhorter, R. J.

    1986-01-01

    Differential electron scattering cross sections have been measured for dipole-forbidden and resonance transitions in Mg II, Zn II and Cd II in the angular range theta = 4-17 deg at 50 eV. These provide the first recorded angular distributions for an optically forbidden transition. It is found that while the cross section for excitation of the 4s (2)S-3d(9)4s(2) (2)D transition in Zn II is small, those for the 3s (2)S-3d (2)D, 4s (2)S (unresolved lines) in Mg II, and the 5s (2)S-4d(9)5s(2) D in Cd II are comparable in magnitude with the cross sections for resonance excitation. In addition, for Cd II it is found that the allowed and forbidden transitions have very similar angular distributions, and it is proposed that excitation to the 2D state may be dominated by a virtual 'double-dipole' transition via the 2P state. Also, the total excitation cross section of the resonance 2P state in Cd II is a factor of four higher than that predicted by the Gaunt factor approximation, suggesting that the accepted value for the oscillator strength may be too low.

  12. Intensive adherence counselling for HIV-infected individuals failing second-line antiretroviral therapy in Johannesburg, South Africa.

    PubMed

    Fox, Matthew P; Berhanu, Rebecca; Steegen, Kim; Firnhaber, Cindy; Ive, Prudence; Spencer, David; Mashamaite, Sello; Sheik, Sadiyya; Jonker, Ingrid; Howell, Pauline; Long, Lawrence; Evans, Denise

    2016-09-01

    In resource-limited settings, where genotypic drug resistance testing is rarely performed and poor adherence is the most common reason for treatment failure, programmatic approaches to handling treatment failure are essential. This study was performed to describe one such approach to adherence optimisation. This was a single-arm study of patients on second-line protease inhibitor (PI)-based antiretroviral therapy (ART) with a HIV-1 RNA ≥400 copies/ml in Johannesburg, South Africa, between 1 March 2012 and 1 December 2013. Patients underwent enhanced adherence counselling. Those with improved adherence and a repeat viral load of >1000 copies/ml underwent HIV-1 drug resistance testing. We describe results using simple proportions and 95% confidence intervals. Of the 400 patients who underwent targeted adherence counselling after an elevated viral load on second-line ART, 388 (97%) underwent repeat viral load testing. Most of these (n = 249; 64%, 95% CI 59-69) resuppressed (<400 copies/ml) on second line. By the end of follow-up (1 March 2014), among the 139 (36%, 95% CI: 31-41%), who did not initially resuppress after being targeted, 106 had a viral load >400 copies/ml, 11 switched to third line, 5 were awaiting third line, 4 had died and 13 were lost to follow-up. Among the unsuppressed, 48 successfully underwent resistance testing with some resistance detected in most (41/48). Most (64%) second-line treatment failure in this clinic is related to adherence and can be overcome with careful adherence support. Controlled interventions are needed to determine what the optimal approach is to improving second-line outcomes and reducing the need for third-line ART. © 2016 John Wiley & Sons Ltd.

  13. Intensity of the Fe XV emission line corona, the level of geomagnetic activity, and the velocity of the solar wind

    NASA Technical Reports Server (NTRS)

    Bell, B.; Noci, G.

    1976-01-01

    The method of superposed epochs is used to determine the average solar wind velocity and the Kp index following central meridian passage of coronal weak and bright features identified from OSO 7 isophotograms of the Fe XV (284 A) emission line. It is found that bright coronal regions possess magnetic fields of closed configuration, thus reducing particle escape, while coronal holes possess open magnetic field lines favorable to particle escape or enhanced outflow of the solar wind.

  14. Spectral line and white-light intensities in the corona in the presence of propagating or standing shocks

    NASA Technical Reports Server (NTRS)

    Esser, Ruth; Habbal, Shadia Rifai

    1990-01-01

    The effect of a propagating shock on the H I Ly-alpha line and the polarization brightness in the inner solar wind region is investigated. The shock produces measurable changes in both, and, provided the measurements are made simultaneously, the alteration of the density and velocity across the shock can be derived. For a standing shock, the effect of the Ly-alpha line and the white-light radiation is much smaller.

  15. A Solar-pumped Fluorescence Model for Line-by-line Emission Intensities in the B-X, A-X, and X-X Band Systems of 12C14N

    NASA Astrophysics Data System (ADS)

    Paganini, L.; Mumma, M. J.

    2016-09-01

    We present a new quantitative model for detailed solar-pumped fluorescent emission of the main isotopologue of CN. The derived fluorescence efficiencies permit estimation and interpretation of ro-vibrational infrared line intensities of CN in exospheres exposed to solar (or stellar) radiation. Our g-factors are applicable to astronomical observations of CN extending from infrared to optical wavelengths, and we compare them with previous calculations in the literature. The new model enables extraction of rotational temperature, column abundance, and production rate from astronomical observations of CN in the inner coma of comets. Our model accounts for excitation and de-excitation of rotational levels in the ground vibrational state by collisions, solar excitation to the {A}2{{{\\Pi }}}{{i}} and {B}2{{{Σ }}}+ electronically excited states followed by cascade to ro-vibrational levels of {X}2{{{Σ }}}+, and direct solar infrared pumping of ro-vibrational levels in the {X}2{{{Σ }}}+ state. The model uses advanced solar spectra acquired at high spectral resolution at the relevant infrared and optical wavelengths and considers the heliocentric radial velocity of the comet (the Swings effect) when assessing the exciting solar flux for a given transition. We present model predictions for the variation of fluorescence rates with rotational temperature and heliocentric radial velocity. Furthermore, we test our fluorescence model by comparing predicted and measured line-by-line intensities for {X}2{{{Σ }}}+ (1-0) in comet C/2014 Q2 (Lovejoy), thereby identifying multiple emission lines observed at IR wavelengths.

  16. Improving central line infection rates in the neonatal intensive care unit: Effect of hospital location, site of insertion, and implementation of catheter-associated bloodstream infection protocols

    PubMed Central

    Freeman, Jennifer J.; Gadepalli, Samir K.; Siddiqui, Sabina M.; Jarboe, Marcus D.; Hirschl, Ronald B.

    2016-01-01

    Introduction Catheter associated blood stream infections (CABSI) are morbid and expensive for all ages, including neonates. Thus far, the impact of CABSI prevention protocols, such as insertion and maintenance bundles, in the neonatal intensive care unit (NICU) is largely unknown. We hypothesized that lines placed in the operating room (OR) would have a lower infection rate due to established insertion protocols and a more sterile environment. Methods Retrospective chart review of NICU patients who received a percutaneous or tunneled central venous catheter between 2005 and 2012. ECMO cannulas, PICC and umbilical catheters were excluded. Variables of interest included demographics, anatomical site, hospital location, line days, and line infection. Line infection was defined as a positive blood culture drawn through the catheter. Results A total of 368 catheters were placed in 285 NICU patients. Majority of catheters (65.5%) were placed in OR. Saphenous and femoral veins were most common anatomical sites (50.8%). Twenty-eight catheters were infected (7.6%). After adjusting for pre-operative antibiotics, anatomical site, and SNAPPE-II scores, lines placed in OR were three times less likely to become infected (Odds Ratio=0.32, p=0.038). Although implementation of CABSI prevention protocols resulted in statistically significant reductions in infection (Odds Ratio=0.4, p=0.043), lines placed in the OR remained less likely to become infected. Conclusions NICU line infection rates decreased with implementation of CABSI prevention protocols. Despite this implementation, catheters placed in the NICU continued to have higher infection rates. As a result, when patient status allows it, we recommend that central lines in newborns be placed in the operating room. PMID:25783394

  17. Evaluation of the Experimental and Theoretical Intensities of Water-Vapor Lines in the 2 μm Region Using Solar-Pointing FTS Spectra

    NASA Astrophysics Data System (ADS)

    Gordon, I. E.; Rothman, L. S.; Lodi, L.; Tennyson, J.; Toon, G. C.; Brown, L. R.

    2012-06-01

    The HITRAN spectroscopic database contains water-vapor absorption lines in a wide spectral range (0-25 000 wn). The precision and accuracy of the transition intensities are diverse and strongly depend on the spectral region and dynamic range. Now, a significant volume of new experimental and theoretical studies must be evaluated region by region prior to inclusion in the next update of HITRAN. For this presentation, we examine the quality of water absorption parameters at 2 μm because they overlap spectral features of prominent CO2 bands that are important to ongoing and future missions (such as GOSAT and OCO-2) designed to monitor the carbon cycle globally from orbit. The accurate knowledge of water-vapor spectral parameters is important not only for accounting for water transitions in spectra, but also for evaluating how pressure broadening of the CO2 lines by water affect atmospheric retrievals. It was determined (using different air-mass retrievals from the solar-pointing Fourier transform spectrometer at Park Falls, WI) that the new ab initio intensities calculated at the University College London have proven to be an improvement over currently tabulated HITRAN intensities, which in the 800-8 000 wn region are based on the semi-empirical values from the SISAM database. In addition, it was found that these new ab initio intensities provide better consistency between the bands in this region (namely 3ν2, ν2+ν3 and ν1+ν2) with respect to previous theoretical attempts. It was also determined that many SISAM experimental intensities are superior to the SISAM semi-empirical values that are now in HITRAN. Lodi L.,Tennyson J., Polyansky O. L., J Chem Phys, 135, 034113-10 (2011). http://mark4sun.jpl.nasa.gov/h2o.html.

  18. The effect of a nursing staff education program on compliance with central line care policy in the cardiac intensive care unit.

    PubMed

    East, Debora; Jacoby, Katherine

    2005-01-01

    Complications related to central venous line use are known to increase patient morbidity and mortality and increase costs and length of hospital stay. Education programs to promote best central line practice have been shown to reduce central line complications. The purpose of this research was to demonstrate the effectiveness of an education module on staff compliance regarding central line care policy in the pediatric cardiovascular intensive care unit (CVICU). A quasi-experimental pre and post-test design was conducted in the CVICU at a major pediatrics hospital in the Southwest. A self-study module was distributed to all RN's working in the CVICU. Pre and post-test results were used to analyze the effectiveness of the education module. Compliance with central line care policy was scored as a "yes" or "no" based upon 10 observable policy requirements. Data was collected on 47 patients over a 1 to 2-month period pre and post intervention during rounds in the CVICU. Results show a marked improvement in compliance with policy.

  19. Impact of International Nosocomial Infection Control Consortium (INICC) strategy on central line-associated bloodstream infection rates in the intensive care units of 15 developing countries.

    PubMed

    Rosenthal, Victor D; Maki, Dennis G; Rodrigues, Camila; Alvarez-Moreno, Carlos; Leblebicioglu, Hakan; Sobreyra-Oropeza, Martha; Berba, Regina; Madani, Naoufel; Medeiros, Eduardo A; Cuéllar, Luis E; Mitrev, Zan; Dueñas, Lourdes; Guanche-Garcell, Humberto; Mapp, Trudell; Kanj, Souha S; Fernández-Hidalgo, Rosalía

    2010-12-01

    The International Nosocomial Infection Control Consortium (INICC) was established in 15 developing countries to reduce infection rates in resource-limited hospitals by focusing on education and feedback of outcome surveillance (infection rates) and process surveillance (adherence to infection control measures). We report a time-sequence analysis of the effectiveness of this approach in reducing rates of central line-associated bloodstream infection (CLABSI) and associated deaths in 86 intensive care units with a minimum of 6-month INICC membership. Pooled CLABSI rates during the first 3 months (baseline) were compared with rates at 6-month intervals during the first 24 months in 53,719 patients (190,905 central line-days). Process surveillance results at baseline were compared with intervention period data. During the first 6 months, CLABSI incidence decreased by 33% (from 14.5 to 9.7 CLABSIs per 1,000 central line-days). Over the first 24 months there was a cumulative reduction from baseline of 54% (from 16.0 to 7.4 CLABSIs per 1,000 central line-days; relative risk, 0.46 [95% confidence interval, 0.33-0.63]; P < .001). The number of deaths in patients with CLABSI decreased by 58%. During the intervention period, hand hygiene adherence improved from 50% to 60% (P < .001); the percentage of intensive care units that used maximal sterile barriers at insertion increased from 45% to 85% (P < .001), that adopted chlorhexidine for antisepsis increased from 7% to 27% (P < .001), and that sought to remove unneeded catheters increased from 37% to 83% (P < .001); and the duration of central line placement decreased from 4.1 to 3.5 days (P < .001). Education, performance feedback, and outcome and process surveillance of CLABSI rates significantly improved infection control adherence, reducing the CLABSI incidence by 54% and the number of CLABSI-associated deaths by 58% in INICC hospitals during the first 2 years.

  20. MRI can identify high intensity bands around implants that correspond to radiolucent lines on radiographs: an ex vivo study of sheep acetabula.

    PubMed

    Hopper, Tim A J; Crawford, Ross W; Timperley, A J; Slaughter, Richard; Pope, James M

    2004-10-01

    We investigated the use of magnetic resonance imaging in categorizing the tissue interface between bone and bone cement after total hip replacement. In an ex vivo sheep model, we compared correlations between the thicknesses of radiolucent lines measured from plain radiographs and corresponding high signal intensity bands in magnetic resonance imaging scans. Correlations obtained for the three main Gruen Zones were in the range between r2 = 0.58 (superior zone), and r2 = 0.86 (inferior zone). In two specimens magnetic resonance imaging was able to detect high signal intensity bands that were not visible on the radiographs. The average thickness of the high signal intensity bands measured on the magnetic resonance imaging scans ranged from 14.6% (Zone 2) to 39.9% (Zone 3) larger than the corresponding radiolucent lines measured on the plain radiographs. Magnetic resonance imaging has the advantage over current techniques in that it is noninvasive and does not use ionizing radiation. If problems associated with metal artifacts can be reduced, these potential advantages may make magnetic resonance imaging the preferred method for longitudinal studies assessing osteointegration and analysis of fibrous membranes.

  1. Electron-correlation effects on the 3C to 3D line-intensity ratio in the Ne-like ions Ar8+ to Kr26+

    DOE PAGES

    Santana, Juan A.; Lepson, Jaan K.; Trabert, Elmar; ...

    2015-01-07

    We present a theoretical and experimental investigation of the 3d→2p resonance to the intercombination line ratio in low- to mid-Z neonlike ions of astrophysical interest, i.e., of the 2p1/22p43/23d3/21Po1 → 2p61S0 and 2p21/22p33/23d5/23Do1 → 2p61S0 transitions commonly labeled 3C and 3D, respectively. In particular, we have employed the configuration-interaction method with three different numbers of basis states and the many-body perturbation theory method to calculate oscillator strengths and energies for neonlike ions from Z = 18 to 36. Combining our calculations with a systematic study of previous works in the literature, we show that these methods can predict accurate andmore » converged energies for these transitions. We also find convergence for the oscillator strengths, but the ratio of oscillator strengths, which can be compared to experimental values of the relative intensity ratios of these lines, appears to converge to values higher than measured. We speculate that this is due to the role of electron-electron correlations. While the amount of electron correlations associated with the intercombination line 3D appears to be well described, it seems that the contributions from highly excited states are not sufficiently accounted for in the case of the resonance line 3C. In order to augment the body of available experimental data for neonlike ions, we present a measurement of the 3C and 3D lines in neonlike Ar8+. We report a wavelength of 41.480±0.001 Å for line 3C and 42.005±0.001 Å for line 3D. Lastly, the intensity ratio of the two lines was determined to be I(3C)/I(3D)=11.32±1.40.« less

  2. Limb-brightening observations from the OSO-7 satellite. II - Comparison of Abel-inverted intensities of Fe XIV and Fe XIII EUV emission lines with predictions

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Rothe, E. D.; Neupert, W. M.

    1976-01-01

    Intensities of Fe XIV and Fe XIII EUV emission lines obtained at coronal locations beyond the limb by the Goddard spectroheliograph on the OSO 7 satellite have been corrected for the wavelength dependence of the instrument's sensitivity and have been Abel-inverted to provide a valid comparison with theoretical predictions for each ion. Details of the Abel-inversion procedure are given, including explicit formulas for application of Bracewell's (1956) method. The intensity ratios of pairs of lines originating from a common level are compared with expected theoretical transition probability ratios over a range of heliocentric distance; deviations in some cases yield information about adjacent unclassified lines. Comparison of the observations with predictions for Fe XIV and Fe XIII shows generally good agreement, with a few interesting discrepancies that may imply a corresponding need for more accurate collisional excitation cross sections. The same comparison yields the variation of electron density with heliocentric radius for each ion separately; the two density functions are found to agree within a factor of three.

  3. Identification of genes responsive to low intensity pulsed ultrasound in a human leukemia cell line Molt-4.

    PubMed

    Tabuchi, Yoshiaki; Ando, Hidetaka; Takasaki, Ichiro; Feril, Loreto B; Zhao, Qing-Li; Ogawa, Ryohei; Kudo, Nobuki; Tachibana, Katsuro; Kondo, Takashi

    2007-02-08

    We examined the gene expression of human leukemia Molt-4 cells treated with non-thermal low intensity pulsed ultrasound. Six hours after 0.3W/cm(2) pulsed ultrasound treatment, apoptosis (24+/-3.3%, mean+/-SD) with minimal cell lysis was observed. Of approximately 16,600 genes analyzed, BCL2-associated athanogene 3 (BAG3), DnaJ (Hsp40) homolog, subfamily B, member 1 (DNAJB1), heat shock 70 kDa protein 1B (HSPA1B), and heat shock 70 kDa protein 6 (HSPA6) showed increased levels of expression while isopentenyl-diphosphate delta isomerase (IDI1) and 3-hydroxy-3-methylglutaryl-coenzyme A synthase 1 (HMGCS1) showed decreased levels in the cells 3h after the ultrasound treatment. The expression levels of these six genes were confirmed by a real-time quantitative polymerase chain reaction. To our knowledge, this is the first report of DNA microarray analysis of genes that are differentially expressed in response to apoptosis induced by non-thermal low intensity pulsed ultrasound in human leukemia cells. The present results will provide a basis for further understanding of the molecular mechanisms of effects of not only low intensity pulsed ultrasound but also that of mechanical shear stress in the cells.

  4. Using forbidden ordinal patterns to detect determinism in irregularly sampled time series.

    PubMed

    Kulp, C W; Chobot, J M; Niskala, B J; Needhammer, C J

    2016-02-01

    It is known that when symbolizing a time series into ordinal patterns using the Bandt-Pompe (BP) methodology, there will be ordinal patterns called forbidden patterns that do not occur in a deterministic series. The existence of forbidden patterns can be used to identify deterministic dynamics. In this paper, the ability to use forbidden patterns to detect determinism in irregularly sampled time series is tested on data generated from a continuous model system. The study is done in three parts. First, the effects of sampling time on the number of forbidden patterns are studied on regularly sampled time series. The next two parts focus on two types of irregular-sampling, missing data and timing jitter. It is shown that forbidden patterns can be used to detect determinism in irregularly sampled time series for low degrees of sampling irregularity (as defined in the paper). In addition, comments are made about the appropriateness of using the BP methodology to symbolize irregularly sampled time series.

  5. Commissioning of a compact laser-based proton beam line for high intensity bunches around 10Â MeV

    NASA Astrophysics Data System (ADS)

    Busold, S.; Schumacher, D.; Deppert, O.; Brabetz, C.; Kroll, F.; Blažević, A.; Bagnoud, V.; Roth, M.

    2014-03-01

    We report on the first results of experiments with a new laser-based proton beam line at the GSI accelerator facility in Darmstadt. It delivers high current bunches at proton energies around 9.6 MeV, containing more than 109 particles in less than 10 ns and with tunable energy spread down to 2.7% (ΔE/E0 at FWHM). A target normal sheath acceleration stage serves as a proton source and a pulsed solenoid provides for beam collimation and energy selection. Finally a synchronous radio frequency (rf) field is applied via a rf cavity for energy compression at a synchronous phase of -90 deg. The proton bunch is characterized at the end of the very compact beam line, only 3 m behind the laser matter interaction point, which defines the particle source.

  6. Radiative Rates for Forbidden Transitions in Doubly-Ionized Fe-Peak Elements

    NASA Astrophysics Data System (ADS)

    Fivet, Vanessa; Quinet, P.; Bautista, M.

    2012-05-01

    Accurate and reliable atomic data for lowly-ionized Fe-peak species (Sc, Ti, V, Cr, Mn, Fe, Co, Ni and Cu) are of paramount importance for the analysis of the high resolution astrophysical spectra currently available. The third spectra of several iron group elements have been observed in different galactic sources like Herbig-Haro objects in the Orion Nebula [1] and stars like Eta Carinae [2]. However, forbidden transitions between low-lying metastable levels of doubly-ionized iron-peak ions have been very little investigated so far and radiative rates for those lines remain sparse or inexistent. We are carrying out a systematic study of the electronic structure of doubly-ionized iron-peak elements. The magnetic dipole (M1) and electric quadrupole (E2) transition probabilities are computed using the pseudo-relativistic Hartree-Fock (HFR) code of Cowan [3] and the central Thomas-Fermi-Dirac potential approximation implemented in AUTOSTRUCTURE [4]. This multi-platform approach allows for consistency checks and intercomparison and has proven very successful in the study of the complex Fe-peak species where many different effects contribute [5]. References [1] A. Mesa-Delgado et al., MNRAS 395 (2009) 855 [2] S. Johansson et al., A&A 361 (2000) 977 [3] R.D. Cowan, The Theory of Atomic Structure and Spectra, Berkeley: Univ. California Press (1981) [4] N.R. Badnell, J. Phys. B: At. Mol. Opt. Phys. 30 (1997) 1 [5] M. Bautista et al., ApJ 718 (2010) L189

  7. Design of a high-current low-energy beam transport line for an intense D-T/D-D neutron generator

    NASA Astrophysics Data System (ADS)

    Lu, Xiaolong; Wang, Junrun; Zhang, Yu; Li, Jianyi; Xia, Li; Zhang, Jie; Ding, Yanyan; Jiang, Bing; Huang, Zhiwu; Ma, Zhanwen; Wei, Zheng; Qian, Xiangping; Xu, Dapeng; Lan, Changlin; Yao, Zeen

    2016-03-01

    An intense D-T/D-D neutron generator is currently being developed at the Lanzhou University. The Cockcroft-Walton accelerator, as a part of the neutron generator, will be used to accelerate and transport the high-current low-energy beam from the duoplasmatron ion source to the rotating target. The design of a high-current low-energy beam transport (LEBT) line and the dynamics simulations of the mixed beam were carried out using the TRACK code. The results illustrate that the designed beam line facilitates smooth transportation of a deuteron beam of 40 mA, and the number of undesired ions can be reduced effectively using two apertures.

  8. Beyond the intensive care unit bundle: Implementation of a successful hospital-wide initiative to reduce central line-associated bloodstream infections.

    PubMed

    Klintworth, Gemma; Stafford, Jane; O'Connor, Mark; Leong, Tim; Hamley, Lee; Watson, Kerrie; Kennon, Jacqueline; Bass, Pauline; Cheng, Allen C; Worth, Leon J

    2014-06-01

    A multimodal hospital-wide central line-associated bloodstream infection (CLABSI) risk reduction strategy was implemented over a 20-month period at an Australian center. Reduced CLABSI rates were observed in both intensive care units (ICUs) (incidence rate ratio [IRR], 0.39; P < .001) and non-ICU wards (IRR, 0.54; P < .001). The median time to CLABSI onset was 7.5 days for ICU events and 13 days for non-ICU events. The timing of infection demonstrates the need for more careful attention to postinsertion care and access of central venous catheters.

  9. Forbidden dark matter at the weak scale via the top portal

    NASA Astrophysics Data System (ADS)

    Delgado, Antonio; Martin, Adam; Raj, Nirmal

    2017-02-01

    At the tail of its velocity distribution, cold dark matter (DM) can annihilate at finite temperature to states heavier than itself. We explore the possibility that DM freeze-out is dictated by these "forbidden annihilations" at the electroweak scale. Demanding that annihilation products be Standard Model particles, we find that for the forbidden mechanism to primarily set the DM relic abundance, DM must couple predominantly, if not solely, to top quarks. This can be arranged by invoking a nontrivial flavor structure such as minimal flavor violation. We avail two avenues to achieve the correct thermal cross section, requiring a mediator exchanged in the s - or t -channel. These simplified models submit easily to direct detection and collider searches, and necessarily hide from indirect detection signals. Viable supersymmetric spectra involving the forbidden mechanism may be found if combined with coannihilation.

  10. Inpatient Peripherally Inserted Central Venous Catheter Complications: Should Peripherally Inserted Central Catheter Lines Be Placed in the Intensive Care Unit Setting?

    PubMed

    Martyak, Michael; Kabir, Ishraq; Britt, Rebecca

    2017-08-01

    Peripherally inserted central venous catheters (PICCs) are now commonly used for central access in the intensive care unit (ICU) setting; however, there is a paucity of data evaluating the complication rates associated with these lines. We performed a retrospective review of all PICCs placed in the inpatient setting at our institution during a 1-year period from January 2013 to December 2013. These were divided into two groups: those placed at the bedside in the ICU and those placed by interventional radiology in non-ICU patients. Data regarding infectious and thrombotic complications were collected and evaluated. During the study period, 1209 PICC line placements met inclusion criteria and were evaluated; 1038 were placed by interventional radiology in non-ICU patients, and 171 were placed at the bedside in ICU patients. The combined thrombotic and central line associated blood stream infection rate was 6.17 per cent in the non-ICU group and 10.53 per cent in the ICU group (P = 0.035). The thrombotic complication rate was 5.88 per cent in the non-ICU group and 7.60 per cent in the ICU group (P = 0.38), whereas the central line associated blood stream infection rate was 0.29 per cent in the non-ICU group and 2.92 per cent in the ICU group (P = 0.002). This study seems to suggest that PICC lines placed at the bedside in the ICU setting are associated with higher complication rates, in particular infectious complications, than those placed by interventional radiology in non-ICU patients. The routine placement of PICC lines in the ICU settings needs to be reevaluated given these findings.

  11. Implementation of central venous catheter bundle in an intensive care unit in Kuwait: Effect on central line-associated bloodstream infections.

    PubMed

    Salama, Mona F; Jamal, Wafaa; Al Mousa, Haifa; Rotimi, Vincent

    2016-01-01

    Central line-associated bloodstream infection (CLABSIs) is an important healthcare-associated infection in the critical care units. It causes substantial morbidity, mortality and incurs high costs. The use of central venous line (CVL) insertion bundle has been shown to decrease the incidence of CLABSIs. Our aim was to study the impact of CVL insertion bundle on incidence of CLABSI and study the causative microbial agents in an intensive care unit in Kuwait. Surveillance for CLABSI was conducted by trained infection control team using National Health Safety Network (NHSN) case definitions and device days measurement methods. During the intervention period, nursing staff used central line care bundle consisting of (1) hand hygiene by inserter (2) maximal barrier precautions upon insertion by the physician inserting the catheter and sterile drape from head to toe to the patient (3) use of a 2% chlorohexidine gluconate (CHG) in 70% ethanol scrub for the insertion site (4) optimum catheter site selection. (5) Examination of the daily necessity of the central line. During the pre-intervention period, there were 5367 documented catheter-days and 80 CLABSIs, for an incidence density of 14.9 CLABSIs per 1000 catheter-days. After implementation of the interventions, there were 5052 catheter-days and 56 CLABSIs, for an incidence density of 11.08 per 1000 catheter-days. The reduction in the CLABSI/1000 catheter days was not statistically significant (P=0.0859). This study demonstrates that implementation of a central venous catheter post-insertion care bundle was associated with a reduction in CLABSI in an intensive care area setting.

  12. Estimation of the Lyman-{alpha} line intensity in a lithium-based discharge-produced plasma source

    SciTech Connect

    Masnavi, Majid; Nakajima, Mitsuo; Hotta, Eiki; Horioka, Kazuhiko

    2008-01-01

    Extreme ultraviolet (EUV) discharge-based lamps for EUV lithography need to generate extremely high power in the narrow spectrum band of 13.5{+-}0.135 nm. A simplified time-dependent collisional-radiative model and radiative transfer solution were utilized to investigate the wavelength-integrated Lyman-{alpha} line light outputs in a hydrogen-like lithium ion. The study reveals in particular that a steady-state or magnetically confined lithium plasma radiates in the desired spectrum band not less than 1 kW in 2{pi} sr even at an ion density region as low as 10{sup 17} cm{sup -3}.

  13. Prediction and identification of some forbidden lines in the Ne I sequence. [in solar spectrum

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.

    1974-01-01

    A magnetic quadrupole transition which according to a prediction by Garstang (1969) is to have an appreciable transition probability in the higher ions of the Ne I sequence has recently been observed in Fe XVII with high resolution by Parkinson (1973), at 17.086 A. Values of an interval predicted by calculations of Crance (1973) are plotted in a graph. Interval values obtained from the curve are used to predict the values of certain transition wavelengths in the ions Si V Cr XV.

  14. A Solar-Pumped Fluorescence Model for Line-By-Line Emission Intensities in the B-X, A-X, and X-X Band Systems of 12C14N

    NASA Technical Reports Server (NTRS)

    Paganini, L.; Mumma, M. J.

    2016-01-01

    We present a new quantitative model for detailed solar-pumped fluorescent emission of the main isotopologue of CN. The derived fluorescence efficiencies permit estimation and interpretation of ro-vibrational infrared line intensities of CN in exospheres exposed to solar (or stellar) radiation. Our g-factors are applicable to astronomical observations of CN extending from infrared to optical wavelengths, and we compare them with previous calculations in the literature. The new model enables extraction of rotational temperature, column abundance, and production rate from astronomical observations of CN in the inner coma of comets. Our model accounts for excitation and de-excitation of rotational levels in the ground vibrational state by collisions, solar excitation to the A(sup 2)Pi(sub I) and B(sup 2)Sum(sup +) electronically excited states followed by cascade to ro-vibrational levels of X(sup 2)Sum(sup +), and direct solar infrared pumping of ro-vibrational levels in the X(sup 2)Sum(sup +) state. The model uses advanced solar spectra acquired at high spectral resolution at the relevant infrared and optical wavelengths and considers the heliocentric radial velocity of the comet (the Swings effect) when assessing the exciting solar flux for a given transition. We present model predictions for the variation of fluorescence rates with rotational temperature and heliocentric radial velocity. Furthermore, we test our fluorescence model by comparing predicted and measured line-by-line intensities for X(sup 2)Sum(sup +) (1-0) in comet C/2014 Q2 (Lovejoy), thereby identifying multiple emission lines observed at IR wavelengths.

  15. A Solar-Pumped Fluorescence Model for Line-By-Line Emission Intensities in the B-X, A-X, and X-X Band Systems of 12C14N

    NASA Technical Reports Server (NTRS)

    Paganini, L.; Mumma, M. J.

    2016-01-01

    We present a new quantitative model for detailed solar-pumped fluorescent emission of the main isotopologue of CN. The derived fluorescence efficiencies permit estimation and interpretation of ro-vibrational infrared line intensities of CN in exospheres exposed to solar (or stellar) radiation. Our g-factors are applicable to astronomical observations of CN extending from infrared to optical wavelengths, and we compare them with previous calculations in the literature. The new model enables extraction of rotational temperature, column abundance, and production rate from astronomical observations of CN in the inner coma of comets. Our model accounts for excitation and de-excitation of rotational levels in the ground vibrational state by collisions, solar excitation to the A(sup 2)Pi(sub I) and B(sup 2)Sum(sup +) electronically excited states followed by cascade to ro-vibrational levels of X(sup 2)Sum(sup +), and direct solar infrared pumping of ro-vibrational levels in the X(sup 2)Sum(sup +) state. The model uses advanced solar spectra acquired at high spectral resolution at the relevant infrared and optical wavelengths and considers the heliocentric radial velocity of the comet (the Swings effect) when assessing the exciting solar flux for a given transition. We present model predictions for the variation of fluorescence rates with rotational temperature and heliocentric radial velocity. Furthermore, we test our fluorescence model by comparing predicted and measured line-by-line intensities for X(sup 2)Sum(sup +) (1-0) in comet C/2014 Q2 (Lovejoy), thereby identifying multiple emission lines observed at IR wavelengths.

  16. Forbidden pitches: causes, source optimization, and their role in design rules

    NASA Astrophysics Data System (ADS)

    Apostol, Štefan; Hurley, Paul

    2015-03-01

    Forbidden pitches are the result of unwanted, non-linear effects that limit yield and not always well understood. Yet, as approximations, they are implicitly deployed through design rules. Many believe they result as a consequence of more complicated light sources. We develop an analytical model of aerial image quality as a function of light source. We show the effect is most pronounced for a point light source, the simplest of all. We develop a method to improve print image quality by illumination source optimization, and show promising first results. Additionally, it is shown how design rules capture forbidden pitches unsatisfactorily.

  17. Bioluminescence imaging of leukemia cell lines in vitro and in mouse xenografts: effects of monoclonal and polyclonal cell populations on intensity and kinetics of photon emission

    PubMed Central

    2013-01-01

    Background We investigated the utility of bioluminescence imaging (BLI) using firefly luciferase in monoclonal and polyclonal populations of leukemia cells in vitro and in vivo. Methods Monoclonal and polyclonal human lymphoid and myeloid leukemia cell lines transduced with firefly luciferase were used for BLI. Results Kinetics and dynamics of bioluminescence signal were cell line dependent. Luciferase expression decreased significantly over time in polyclonal leukemia cells in vitro. Transplantation of polyclonal luciferase-tagged cells in mice resulted in inconsistent signal intensity. After selection of monoclonal cell populations, luciferase activity was stable, equal kinetic and dynamic of bioluminescence intensity and strong correlation between cell number and light emission in vitro were observed. We obtained an equal development of leukemia burden detected by luciferase activity in NOD-scid-gamma mice after transplantation of monoclonal populations. Conclusion The use of monoclonal leukemia cells selected for stable and equal luciferase activity is recommended for experiments in vitro and xenograft mouse models. The findings are highly significant for bioluminescence imaging focused on pre-clinical drug development. PMID:23343252

  18. The oxygen red OI 630.0 nm line nightglow intensity as an indicator of atmospheric waves propagation in the mid-latitude ionosphere F2 region

    NASA Astrophysics Data System (ADS)

    Javakhishvili, Giorgi; Didebulidze, Goderdzi; Gudadze, Nikoloz; Toriashvili, Lexo

    2016-04-01

    The behavior of the oxygen red OI 630.0 nm line nightglow intensity under influence of atmospheric gravity waves (AGWs) is considered, taking into account nightly changes of the thermosphere meridional wind by observations from Abastumani (41.75 N; 42.82 E). The vortical type perturbations, which can be in situ excited, are also considered. On the basis of theoretical model, the 630.0 nm line integral intensity variations are estimated taking into account thermosphere wind field changes and atmospheric waves propagation influence on the nighttime ionosphere F2 layer. A possibility of identification of waves propagation from polar and equatorial regions during various helio-geophysical conditions is noted. The cases of detected large scale traveling ionosphere disturbances -TIDs (mostly generated in the polar regions) and traveling atmospheric disturbances -TADs (which can be generated both in polar and equatorial regions) are demonstrated. Acknowledgements: This work has been supported by Shota Rustaveli National Science Foundation Grant no. 31/56.

  19. Relationship between Fluorescence Intensity of GFP and the Expression Level of Prestin in a Prestin-Expressing Chinese Hamster Ovary Cell Line

    NASA Astrophysics Data System (ADS)

    Iida, Koji; Nagaoka, Tomoyuki; Tsumoto, Kouhei; Ikeda, Katsuhisa; Kumagai, Izumi; Kobayashi, Toshimitsu; Wada, Hiroshi

    Outer hair cells (OHCs) in mammals can elongate and contract at frequencies up to 100kHz in response to changes in their membrane potential. The origin of this unique motility is the motor protein prestin, which is densely packed in the lateral membrane of the OHCs. In a previous work, we constructed a prestin-expressing cell line using Chinese hamster ovary (CHO) cells to obtain a stable supply of prestin. When we research prestin using constructed cells, it is necessary to estimate the expression level of prestin in the cells easily and non-invasively. As the prestin gene and a green fluorescent protein (GFP) gene were introduced into constructed cells using the same vector, the expression level of prestin and fluorescence intensity of GFP are possibly correlated. Since this correlation is not clear, however, in this study, we therefore investigated whether the expression level of prestin evaluated by patch-clamp recording and the fluorescence intensity of GFP obtained from fluorescence images are correlated or not. As a result, it was demonstrated that they were correlated. The expression level of prestin can therefore be evaluated by measuring the fluorescence intensity of GFP.

  20. Line Positions, Intensities, - and N_2-BROADENING Parameters in the ν_9 Band of Ethane (C_2H_6)

    NASA Astrophysics Data System (ADS)

    Rinsland, Curtis P.; Devi, V. Malathy; Benner, D. Chris; Sams, Robert L.; Blake, Thomas A.

    2009-06-01

    High-resolution infrared spectra of ethane have been recorded using the Bruker IFS 120 HR Fourier transform spectrometer (FTS) at the Pacific Northwest National Laboratory (PNNL), in Richland, Washington. Several spectra of pure ethane and ethane in N_2 mixtures were obtained with absorption paths of 20 cm and 3.2 m. Room temperature spectra were obtained in both 20 cm and 3.2 m paths while cold spectra were obtained using only the 20 cm path cell. The spectra were obtained at ˜0.0028 cm^{-1} resolution with sample pressures ranging from 0.3 to ˜36 torr for pure ethane and 11 to 180 torr in ethane-N_2 mixtures. The volume mixing ratios of ethane in the ethane-N_2 mixtures varied between 0.01 and 0.2. The gas temperatures varied from -66^°C to 24^°C. Positions, intensities, self- and N_2-broadening parameters were determined by processing 16 or 17 room temperature spectra using the multispectrum nonlinear least squares spectrum fitting technique. The results obtained for transitions in a few select ^PQ and ^RQ sub-bands will be reported at this time. D. Chris Benner, C.P. Rinsland, V. Malathy Devi, M.A.H. Smith, and D. Atkins, J. Quant. Spectrosc. Radiat. Transfer 53, 705-721 (1995)

  1. An improved pulse-line accelerator-driven, intense current-density, and high-brightness pseudospark electron beam

    SciTech Connect

    Zhu, J.; Wang, Z.; Zhang, L.; Wang, M.

    1996-02-01

    A high-voltage (200 kV), high current-density, low-emittance (23 {pi}{center_dot}mm mrd), high-brightness (8 {times} 10{sup 10} A/(mrd){sup 2}) electron beam was generated in a pseudospark chamber filled with 15 Pa nitrogen and driven by a modified pulse line accelerator. The beam ejected with {le}1-mm diameter, 2.2-kA beam current, 400-ns pulse length, and about 20 cm propagation distance. Exposure of 10 shots on the same film produced a hole of 1.6-mm diameter at 7 cm downstream of the anode, and showed its good reproducibility. After 60 shots, it was observed that almost no destructive damage traces were left on the surfaces of the various electrodes and insulators of the pseudospark discharge chamber. It was experimentally found that the quality of the pseudospark electron beam remains very high, even at high voltages (of several hundred kilovolts), similar to low voltages, and is much better than the quality of the cold-cathode electron beams.

  2. Predictive factors for the development of central line-associated bloodstream infection due to gram-negative bacteria in intensive care unit patients after surgery.

    PubMed

    Sreeramoju, Pranavi V; Tolentino, Jocelyn; Garcia-Houchins, Sylvia; Weber, Stephen G

    2008-01-01

    To examine the relative proportions of central line-associated bloodstream infection (BSI) due to gram-negative bacteria and due to gram-positive bacteria among patients who had undergone surgery and patients who had not. The study also evaluated clinical predictive factors and unadjusted outcomes associated with central line-associated BSI caused by gram-negative bacteria in the postoperative period. Observational, case-control study based on a retrospective review of medical records. University of Chicago Medical Center, a 500-bed tertiary care center located on Chicago's south side. Adult intensive care unit (ICU) patients who developed central line-associated BSI. There were a total of 142 adult patients who met the Centers for Disease Control and Prevention National Nosocomial Infection Surveillance System definition for central line-associated BSI. Of those, 66 patients (46.5%) had infections due to gram-positive bacteria, 49 patients (34.5%) had infections due to gram-negative bacteria, 23 patients (16.2%) had infections due to yeast, and 4 patients (2.8%) had mixed infections. Patients who underwent surgery were more likely to develop central line-associated BSI due to gram-negative bacteria within 28 days of the surgery, compared with patients who had not had surgery recently (57.6% vs 27.3%; P= .002). On multivariable logistic regression analysis, diabetes mellitus (adjusted odds ratio [OR], 4.6 [95% CI, 1.2-18.1]; P= .03) and the presence of hypotension at the time of the first blood culture positive for a pathogen (adjusted OR, 9.8 [95% CI, 2.5-39.1]; P= .001) were found to be independently predictive of central line-associated BSI caused by gram-negative bacteria. Unadjusted outcomes were not different in the group with BSI due to gram-negative pathogens, compared to the group with BSI due to gram-positive pathogens. Clinicians caring for critically ill patients after surgery should be especially concerned about the possibility of central line

  3. High sensitivity cavity ring down spectroscopy of N2O near 1.22 μm: (II) 14N216O line intensity modeling and global fit of 14N218O line positions

    NASA Astrophysics Data System (ADS)

    Tashkun, S. A.; Perevalov, V. I.; Karlovets, E. V.; Kassi, S.; Campargue, A.

    2016-06-01

    In a recent work (Karlovets et al., 2016 [1]), we reported the measurement and rovibrational assignments of more than 3300 transitions belonging to 64 bands of five nitrous oxide isotopologues (14N216O, 14N15N16O, 15N14N16O, 14N218O and 14N217O) in the high sensitivity CRDS spectrum recorded in the 7915-8334 cm-1 spectral range. The assignments were performed by comparison with predictions of the effective Hamiltonian models developed for each isotopologue. In the present paper, the large amount of measurements from our previous work mentioned above and literature are gathered to refine the modeling of the nitrous oxide spectrum in two ways: (i) improvement of the intensity modeling for the principal isotopologue, 14N216O, near 8000 cm-1 from a new fit of the relevant effective dipole moment parameters, (ii) global modeling of 14N218O line positions from a new fit of the parameters of the global effective Hamiltonian using an exhaustive input dataset collected in the literature in the 12-8231 cm-1 region. The fitted set of 81 parameters allowed reproducing near 5800 measured line positions with an RMS deviation of 0.0016 cm-1. The dimensionless weighted standard deviation of the fit is 1.22. As an illustration of the improvement of the predictive capabilities of the obtained effective Hamiltonian, two new 14N218O bands could be assigned in the CRDS spectrum in the 7915-8334 cm-1 spectral range. A line list at 296 K has been generated in the 0-10,700 cm-1 range for 14N218O in natural abundance with a 10-30 cm/molecule intensity cutoff.

  4. Nitroxyl free radical enhancement of the forbidden singlet oxygen luminescent transition

    SciTech Connect

    Belford, R.E.

    1993-01-01

    Utilizing transient near IR luminescence spectroscopy, nitroxyl free radicals like TEMPO, (2,2,6,6-tetramethyl piperidine-N-oxyl), have been shown to increase the rate of quantum mechanically forbidden O[sub 2]([sup 3][Sigma][sub g][sup [minus

  5. Magnetic circular dichroism of molecules in dense media: Spin-forbidden transitions of carbonyl molecules

    PubMed Central

    Yoon, Y. H.; Lee, S. T.; Lin, S. H.; Eyring, H.

    1976-01-01

    The purpose of this paper has been to calculate the magnetic rotational strength of the spin-forbidden 1A1 → 3A2 transition of the carbonyl group. For this purpose, simple molecular orbitals have been used and only one-center integrals have been considered. The calculated results have been compared with the experimental measurements. PMID:16592346

  6. Magnetic circular dichroism of molecules in dense media: Spin-forbidden transitions of carbonyl molecules.

    PubMed

    Yoon, Y H; Lee, S T; Lin, S H; Eyring, H

    1976-09-01

    The purpose of this paper has been to calculate the magnetic rotational strength of the spin-forbidden (1)A(1) --> (3)A(2) transition of the carbonyl group. For this purpose, simple molecular orbitals have been used and only one-center integrals have been considered. The calculated results have been compared with the experimental measurements.

  7. Physical processes in an electron current layer causing intense plasma heating and formation of x-lines

    NASA Astrophysics Data System (ADS)

    Singh, Nagendra; Khazanov, Igor; Wells, B. E.

    2015-05-01

    We study the evolution of an electron current layer (ECL) through its several stages by means of three-dimensional particle-in-cell (PIC) simulations with ion to electron mass ratio M/me = 400. An ECL evolves through the following stages: (i) Electrostatic (ES) current-driven instability (CDI) soon after its formation with half width w about 2 electron skin depth (de), (ii) current disruption in the central part of the ECL by trapping of electrons and generation of anomalous resistivity, (iii) electron tearing instability (ETI) with significantly large growth rates in the lower end of the whistler frequency range, (iv) widening of the ECL and modulation of its width by the ETI, (v) gradual heating of electrons by the CDI-driven ES ion modes create the condition that the electrons become hotter than the ions, (vi) despite the reduced electron drift associated with the current disruption by the CDI, the enhanced electron temperature continues to favor a slow growth of the ion waves reaching nonlinear amplitudes, (vii) the nonlinear ion waves undergo modulation and collapse into localized density cavities containing spiky electric fields like in double layers (DLs), (viii) such spiky electric fields are very effective in further rapid heating of both electrons and ions. As predicted by the electron magnetohydrodynamic (EMHD) theories, the ETI growth rate maximizes at wave numbers in the range 0.4 < kxW < 0.8 where kx is the wave number parallel to the ECL magnetic field and w is the evolving half width of the ECL. The developing ETI generates in-plane currents that support out-of-plane magnetic fields around the emerging x-lines. The ETI and the spiky electrostatic structures are accompanied by fluctuations in the magnetic fields near and above the lower-hybrid (ion plasma) frequency, including the whistler frequency range. We compare our results with experimental results and satellite observation.

  8. Physical processes in an electron current layer causing intense plasma heating and formation of x-lines

    SciTech Connect

    Singh, Nagendra; Wells, B. E.; Khazanov, Igor

    2015-05-15

    We study the evolution of an electron current layer (ECL) through its several stages by means of three-dimensional particle-in-cell (PIC) simulations with ion to electron mass ratio M/m{sub e} = 400. An ECL evolves through the following stages: (i) Electrostatic (ES) current-driven instability (CDI) soon after its formation with half width w about 2 electron skin depth (d{sub e}), (ii) current disruption in the central part of the ECL by trapping of electrons and generation of anomalous resistivity, (iii) electron tearing instability (ETI) with significantly large growth rates in the lower end of the whistler frequency range, (iv) widening of the ECL and modulation of its width by the ETI, (v) gradual heating of electrons by the CDI-driven ES ion modes create the condition that the electrons become hotter than the ions, (vi) despite the reduced electron drift associated with the current disruption by the CDI, the enhanced electron temperature continues to favor a slow growth of the ion waves reaching nonlinear amplitudes, (vii) the nonlinear ion waves undergo modulation and collapse into localized density cavities containing spiky electric fields like in double layers (DLs), (viii) such spiky electric fields are very effective in further rapid heating of both electrons and ions. As predicted by the electron magnetohydrodynamic (EMHD) theories, the ETI growth rate maximizes at wave numbers in the range 0.4 < k{sub x}W < 0.8 where k{sub x} is the wave number parallel to the ECL magnetic field and w is the evolving half width of the ECL. The developing ETI generates in-plane currents that support out-of-plane magnetic fields around the emerging x-lines. The ETI and the spiky electrostatic structures are accompanied by fluctuations in the magnetic fields near and above the lower-hybrid (ion plasma) frequency, including the whistler frequency range. We compare our results with experimental results and satellite observation.

  9. Electron impact excitation of Fe-peak elements: forbidden transitions in the 3d5 manifold of Fe IV

    NASA Astrophysics Data System (ADS)

    McLaughlin, B. M.; Hibbert, A.; Scott, M. P.; Noble, C. J.; Burke, V. M.; Burke, P. G.

    2005-06-01

    Electron-impact excitation collision strengths of the Fe-peak element Fe IV are calculated in the close-coupling approximation using the R-matrix suite of codes PRMAT designed for parallel processors. One hundred and eight LS-coupled states arising from the 3d5, 3d44s and 3d44p configurations of Fe IV, are retained in the present calculations. Detailed multi-configuration interaction target wavefunctions are used with the aid of 3p2 → 3d2 electron promotions and a \\rm 4\\overline{d} correlation orbital in the present calculations. Effective collision strengths for optically forbidden transitions, which are extremely important in the analysis of lines in the Fe IV spectra, are obtained by averaging the electron collision strengths for a wide range of incident electron energies, over a Maxwellian distribution of velocities. Results are presented for electron temperatures (Te in Kelvin) in the range 3.3 <= Log Te<= 6.0 applicable to many laboratory and astrophysical plasmas for transitions within the 3d5 manifold. The present results compared to previous investigations provide improved results for important lines in the Fe IV spectrum.

  10. Overview spectra and axial distribution of spectral line intensities in a high-current vacuum arc with CuCr electrodes

    SciTech Connect

    Lisnyak, M.; Pipa, A. V.; Gorchakov, S. E-mail: weltmann@inp-greifswald.de; Iseni, S.; Franke, St.; Khapour, A.; Methling, R.; Weltmann, K.-D. E-mail: weltmann@inp-greifswald.de

    2015-09-28

    Spectroscopic investigations of free-burning vacuum arcs in diffuse mode with CuCr electrodes are presented. The experimental conditions of the investigated arc correspond to the typical system for vacuum circuit breakers. Spectra of six species Cu I, Cu II, Cu III, Cr I, Cr II, and Cr III have been analyzed in the wavelength range 350–810 nm. The axial intensity distributions were found to be strongly dependent on the ionization stage of radiating species. Emission distributions of Cr II and Cu II can be distinguished as well as the distributions of Cr III and Cu III. Information on the axial distribution was used to identify the spectra and for identification of overlapping spectral lines. The overview spectra and some spectral windows recorded with high resolution are presented. Analysis of axial distributions of emitted light, which originates from different ionization states, is presented and discussed.

  11. The unusual emission line spectrum of I Zw 1

    NASA Astrophysics Data System (ADS)

    Joly, Monique; Véron-Cetty, M.-P.; Véron, P.

    2004-11-01

    A detailed analysis of the spectrum of I Zw 1 shows that the Narrow Line Region, unlike that of most Seyfert 1 galaxies, is a very low excitation region dominated by both permitted and forbidden Fe II lines. The physical conditions in this region are discussed.

  12. Emission intensity of the λ = 1.54 μm line in ZnO films grown by magnetron sputtering, diffusion doped with Ce, Yb, Er

    SciTech Connect

    Mezdrogina, M. M. Eremenko, M. V.; Smirnov, A. N.; Petrov, V. N.; Terukov, E. I.

    2015-08-15

    The effect of the Er{sup 3+}-ion excitation type on the photoluminescence spectra of crystalline ZnO(ZnO〈Ce, Yb, Er〉) films is determined in the cases of resonant (λ = 532 nm, Er{sup 3+}-ion transition from {sup 4}S{sub 3/2}, {sup 2}H{sub 11/2} levels to {sup 4}I{sub 15/2}) and non-resonant (λ = 325 nm, in the region near the ZnO band-edge emission) excitation. It is shown that resonant excitation gives rise to lines with various emission intensities, characteristic of the Er{sup 3+}-ion intracenter 4f transition with λ = 1535 nm when doping crystalline ZnO films with three rare-earth ions (REIs, Ce, Yb, Er) or with two impurities (Ce, Er) or (Er, Yb), independently of the measurement temperature (T = 83 and 300 K). The doping of crystalline ZnO films with rare-earth impurities (Ce, Yb, Er) leads to the efficient transfer of energy to REIs, a consequence of which is the intense emission of an Er{sup 3+} ion in the IR spectral region at λ{sub max} = 1535 nm. The kick-out diffusion mechanism is used upon the sequential introduction of impurities into semiconductor matrices and during the postgrowth annealing of the ZnO films under study. The crystalline ZnO films doped with Ce, Yb, Er also exhibit intense emission in the visible spectral region at room temperature, which makes them promising materials for optoelectronics.

  13. Mesosphere-thermosphere regions coupling with the lower atmosphere through the inter-annual variations of the hydroxyl OH(8-3) bands, the oxygen 557.7 nm and 630.0 nm lines nightglow intensities

    NASA Astrophysics Data System (ADS)

    Didebulidze, Goderdzi; Javakhishvili, Giorgi; Todua, Maya; Toriashvili, Lekso

    2016-04-01

    The characteristics of the inter-annual/seasonal distributions of the mid-latitude nightglow intensities of the mesopause hydroxyl OH(8-3) bands (maximum luminous layer about 87 km), the thermosphere oxygen green 557.7 nm (main maximum of luminous layer in the lower thermosphere at about 95 km) and the red 630.0 nm line (emitted from the ionosphere F2 region with maximum luminous layer about 230-280 km) intensities are considered by observations from Abastumani (41.75 E; 42.82 E). The observed inter-annual variations of the OH bands and green line, along with the maximal values at spring (March-April) and fall (September-October) equinoxial periods which are noticed also from other regions, exhibit maxima in June as well. The red line intensity mainly tends to decrease at equinoxial months, while it is maximal in summer and is accompanied by relatively small increase in June (compared to May and July). Maximal values of OH band and green line intensities in June are observed both in maximum and minimum phases of solar activity. This is considered as a manifestation of the features of upper and lower atmosphere dynamical coupling of this region of the South Caucasus. Such dynamical coupling can involve the ionosphere F2 region and can be accompanied by relative decrease of the red line intensity in June. It is observed that the increase of OH band and green line intensities is accompanied by the red line intensity decrease at the end of March and beginning of April, which also is considered as a manifestation of lower and upper atmosphere dynamical coupling. Acknowledgements: This work has been supported by Shota Rustaveli National Science Foundation Grants no. 31/56 and 31/81.

  14. PORTA: A three-dimensional multilevel radiative transfer code for modeling the intensity and polarization of spectral lines with massively parallel computers

    NASA Astrophysics Data System (ADS)

    Štěpán, Jiří; Trujillo Bueno, Javier

    2013-09-01

    The interpretation of the intensity and polarization of the spectral line radiation produced in the atmosphere of the Sun and of other stars requires solving a radiative transfer problem that can be very complex, especially when the main interest lies in modeling the spectral line polarization produced by scattering processes and the Hanle and Zeeman effects. One of the difficulties is that the plasma of a stellar atmosphere can be highly inhomogeneous and dynamic, which implies the need to solve the non-equilibrium problem of the generation and transfer of polarized radiation in realistic three-dimensional (3D) stellar atmospheric models. Here we present PORTA, an efficient multilevel radiative transfer code we have developed for the simulation of the spectral line polarization caused by scattering processes and the Hanle and Zeeman effects in 3D models of stellar atmospheres. The numerical method of solution is based on the non-linear multigrid iterative method and on a novel short-characteristics formal solver of the Stokes-vector transfer equation which uses monotonic Bézier interpolation. Therefore, with PORTA the computing time needed to obtain at each spatial grid point the self-consistent values of the atomic density matrix (which quantifies the excitation state of the atomic system) scales linearly with the total number of grid points. Another crucial feature of PORTA is its parallelization strategy, which allows us to speed up the numerical solution of complicated 3D problems by several orders of magnitude with respect to sequential radiative transfer approaches, given its excellent linear scaling with the number of available processors. The PORTA code can also be conveniently applied to solve the simpler 3D radiative transfer problem of unpolarized radiation in multilevel systems.

  15. The epidemiology of tick-borne haemoparasites as determined by the reverse line blot hybridization assay in an intensively studied cohort of calves in western Kenya

    PubMed Central

    Njiiri, Nyawira E.; Bronsvoort, B. Mark deC.; Collins, Nicola E.; Steyn, Helena C.; Troskie, Milana; Vorster, Ilse; Thumbi, S.M.; Sibeko, Kgomotso P.; Jennings, Amy; van Wyk, Ilana Conradie; Mbole-Kariuki, Mary; Kiara, Henry; Poole, E. Jane; Hanotte, Olivier; Coetzer, Koos; Oosthuizen, Marinda C.; Woolhouse, Mark; Toye, Philip

    2015-01-01

    The development of sensitive surveillance technologies using PCR-based detection of microbial DNA, such as the reverse line blot assay, can facilitate the gathering of epidemiological information on tick-borne diseases, which continue to hamper the productivity of livestock in many parts of Africa and elsewhere. We have employed a reverse line blot assay to detect the prevalence of tick-borne parasites in an intensively studied cohort of indigenous calves in western Kenya. The calves were recruited close to birth and monitored for the presence of infectious disease for up to 51 weeks. The final visit samples from 453 calves which survived for the study period were analyzed by RLB. The results indicated high prevalences of Theileria mutans (71.6%), T. velifera (62.8%), Anaplasma sp. Omatjenne (42.7%), A. bovis (39.9%), Theileria sp. (sable) (32.7%), T. parva (12.9%) and T. taurotragi (8.5%), with minor occurrences of eight other haemoparasites. The unexpectedly low prevalence of the pathogenic species Ehrlichia ruminantium was confirmed by a species-specific PCR targeting the pCS20 gene region. Coinfection analyses of the seven most prevalent haemoparasites indicated that they were present as coinfections in over 90% of the cases. The analyses revealed significant associations between several of the Theileria parasites, in particular T. velifera with Theileria sp. sable and T. mutans, and T. parva with T. taurotragi. There was very little coinfection of the two most common Anaplasma species, although they were commonly detected as coinfections with the Theileria parasites. The comparison of reverse line blot and serological results for four haemoparasites (T. parva, T. mutans, A. marginale and B. bigemina) indicated that, except for the mostly benign T. mutans, indigenous cattle seem capable of clearing infections of the three other, pathogenic parasites to below detectable levels. Although the study site was located across four agroecological zones, there was

  16. Daily skin cleansing with chlorhexidine did not reduce the rate of central-line associated bloodstream infection in a surgical intensive care unit.

    PubMed

    Popovich, Kyle J; Hota, Bala; Hayes, Robert; Weinstein, Robert A; Hayden, Mary K

    2010-05-01

    Cleansing the skin of intensive care unit (ICU) patients daily with chlorhexidine gluconate (CHG) has been associated with beneficial effects, including a reduction in central-line-associated bacteremias (CLABSIs). Most studies have been done in medical ICUs. In this study, we evaluated the effectiveness of daily chlorhexidine skin cleansing on CLABSI rates in a surgical ICU. In Fall 2005, the 30-bed surgical ICU at Rush University Medical Center discontinued daily soap-and-water bathing of patients and substituted skin cleansing with no-rinse, 2% CHG-impregnated cloths. This change was made without research investigator input or oversight. Using administrative, microbiological and infection control practitioner databases, we compared rates of CLABSIs and blood culture contamination during soap-and-water bathing (September 2004-October 2005) and CHG cleansing (November 2005-October 2006) periods. Rates of other nosocomial infections that were not expected to be affected by CHG bathing (secondary bacteremia, Clostridium difficile-associated diarrhea, ventilator-associated pneumonia, urinary tract infection) were included as control variables. There was no significant difference in the CLABSI rate between soap-and-water and CHG bathing periods (3.81/1,000 central line days vs. 4.6/1,000 central line days; p = 0.57). Blood culture contamination declined during CHG bathing (5.97/1,000 to 2.41/1,000 patient days; p = 0.003). Rates of other nosocomial infections did not change significantly. In this real-world effectiveness trial, daily cleansing of surgical ICU patients' skin with CHG had no effect on CLABSI rates, but was associated with half the rate of blood culture contamination. Controlled trials in surgical ICUs are needed to determine whether CHG bathing can prevent infections in this setting.

  17. Reduction of central line infections in Veterans Administration intensive care units: an observational cohort using a central infrastructure to support learning and improvement.

    PubMed

    Render, Marta L; Hasselbeck, Rachael; Freyberg, Ron W; Hofer, Timothy P; Sales, Anne E; Almenoff, Peter L

    2011-08-01

    Elimination of hospital-acquired infections is an important patient safety goal. All 174 medical, cardiac, surgical and mixed Veterans Administration (VA) intensive care units (ICUs). A centralised infrastructure (Inpatient Evaluation Center (IPEC)) supported the practice bundle implementation (handwashing, maximal barriers, chlorhexidinegluconate site disinfection, avoidance of femoral catheterisation and timely removal) to reduce central line-associated bloodstream infections (CLABSI). Support included recruiting leadership, benchmarked feedback, learning tools and selective mentoring. Sites recorded the number of CLABSI, line days and audit results of bundle compliance on a secure website. CLABSI rates between years were compared with incidence rate ratios (IRRs) from a Poisson regression and with National Healthcare Safety Network referent rates (standardised infection ratio (SIR)). Pearson's correlation coefficient compared bundle adherence with CLABSI rates. Semi-structured interviews with teams struggling to reduce CLABSI identified common themes. From 2006 to 2009, CLABSI rates fell (3.8-1.8/1000 line days; p<0.01); as did IRR (2007; 0.83 (95% CI 0.73 to 0.94), 2008; 0.65 (95% CI 0.56 to 0.76), 2009; 0.47 (95% CI 0.40 to 0.55)). Bundle adherence and CLABSI rates showed strong correlation (r = 0.81). VA CLABSI SIR, January to June 2009, was 0.76 (95% CI 0.69 to 0.90), and for all FY2009 0.88 (95% CI 0.80 to 0.97). Struggling sites lacked a functional team, forcing functions and feedback systems. Capitalising on a large healthcare system, VA IPEC used strategies applicable to non-federal healthcare systems and communities. Such tactics included measurement through information technology, leadership, learning tools and mentoring.

  18. Development of trigger-based semi-automated surveillance of ventilator-associated pneumonia and central line-associated bloodstream infections in a Dutch intensive care

    PubMed Central

    2014-01-01

    Background Availability of a patient data management system (PDMS) has created the opportunity to develop trigger-based electronic surveillance systems (ESSs). The aim was to evaluate a semi-automated trigger-based ESS for the detection of ventilator-associated pneumonia (VAP) and central line-associated blood stream infections (CLABSIs) in the intensive care. Methods Prospective comparison of surveillance was based on a semi-automated ESS with and without trigger. Components of the VAP/CLABSI definition served as triggers. These included the use of VAP/CLABSI-related antibiotics, the presence of mechanical ventilation or an intravenous central line, and the presence of specific clinical symptoms. Triggers were automatically fired by the PDMS. Chest X-rays and microbiology culture results were checked only on patient days with a positive trigger signal from the ESS. In traditional screening, no triggers were used; therefore, chest X-rays and culture results had to be screened for all patient days of all included patients. Patients with pneumonia at admission were excluded. Results A total of 553 patients were screened for VAP and CLABSI. The incidence of VAP was 3.3/1,000 ventilation days (13 VAP/3,927 mechanical ventilation days), and the incidence of CLABSI was 1.7/1,000 central line days (24 CLABSI/13.887 central line days). For VAP, the trigger-based screening had a sensitivity of 92.3%, a specificity of 100%, and a negative predictive value of 99.8% compared to traditional screening of all patients. For CLABSI, sensitivity was 91.3%, specificity 100%, and negative predictive value 99.6%. Conclusions Pre-selection of patients to be checked for signs and symptoms of VAP and CLABSI by a computer-generated automated trigger system was time saving but slightly less accurate than conventional surveillance. However, this after-the-fact surveillance was mainly designed as a quality indicator over time rather than for precise determination of infection rates. Therefore

  19. Highly Forbidden Transitions in Alkalis: Preparations for a Parity Violation Experiment

    NASA Astrophysics Data System (ADS)

    Oliveira, Claudia

    Preparatory steps for the experimental investigation of the highly forbidden 5s → 6s transition in rubidium using an atom trap and laser cooling are reported. A magneto-optical trap (MOT) has been assembled including saturation spectroscopy and a dichroic vapor laser lock. A frequency-doubled diode laser system has been installed to perform the spectroscopy of the forbidden transition with cold Rb atoms in the trap. The properties of the ns → n's transition in the presence of an external electric field have been investigated theoretically. A first measurement will be exploring the Stark-induced transition amplitude and the very faint magnetic dipole amplitude. The rubidium experiment is a precursor study for a long-term project at TRIUMF, Canada's National Laboratory for nuclear and particle physics, to measure atomic parity violation in the equivalent 7s → 8s transition in francium, the heaviest alkali atom which has no stable isotopes.

  20. Energy transfer enhancement by oxygen perturbation of spin-forbidden electronic transitions in aromatic systems

    NASA Astrophysics Data System (ADS)

    Monguzzi, A.; Tubino, R.; Salamone, M. M.; Meinardi, F.

    2010-09-01

    Triplet-triplet energy transfer in multicomponent organic systems is usually entirely ascribed to a Dexter-type mechanism involving only short-range donor/acceptor interactions. We demonstrate that the presence of molecular oxygen introduces a perturbation to the electronic structure of one of the involved moieties which can induce a large increase in the spin-forbidden transition oscillator strength so that the otherwise negligible Förster contribution dominates the overall energy transfer rate.

  1. Contribution of a pure NCG forbidden process to the Z associated Higgs production

    SciTech Connect

    Bradji, O.; Mebarki, N.

    2012-06-27

    The contribution of the pure NCG forbidden subprocess gg{yields}ZHis calculated. It is shown that the cross section becomes important at the LHC energies and depends strongly on the choice of the noncommutativity parameter. Because of the gluons luminosity inside the proton, it becomes comparable to that of the commutative standard model subprocess qq(bar sign)ZH for reasonable values of the NCG parameter.

  2. Creation of graphic database specifying android arm mechanism work envelope taking into account forbidden zones position

    NASA Astrophysics Data System (ADS)

    Pritykin, F. N.; Nebritov, V. I.

    2017-06-01

    The structure of graphic database specifying the shape and the work envelope projection position of an android arm mechanism with various positions of the known in advance forbidden zones is proposed. The technique of analytical assignment of the work envelope based on the methods of analytical geometry and theory of sets is represented. The conducted studies can be applied in creation of knowledge bases for intellectual systems of android control functioning independently in the sophisticated environment.

  3. New Line Lists Including Intensities for the {C_2} Swan System (d^3Π{_g}-a^3Π{_u}), {C_2} Singlet Systems and Rovibrational Transitions Within the NH X^3Σ{^-} Ground State.

    NASA Astrophysics Data System (ADS)

    Brooke, J. S. A.; Bernath, P. F.; Western, C. M.; Schmidt, T. W.; Bacskay, G. B.; Hemert, M. C. Van; Groenenboom, G. C.

    2013-06-01

    Line lists including both positions and absolute intensities are required by those who wish to calculate abundances from spectroscopic observations. New line lists for the diatomic molecules {C_2} and NH are presented. Line strengths for the {C_2} Swan system (d^3Π{_g}-a^3Π{_u}) have been calculated for vibrational bands with v'=0-10 and v''=0-9, and J values up to J=34-96, based on previous observations in 36 vibrational bands. Line positions from several sources were combined with the results from recent deperturbation studies of the v'=4 and v'=6 levels, to provide updated molecular constants. The line strengths are based on a recent ab initio calculation of the transition dipole moment function. Einstein A coefficients and f-values were also calculated for the vibrational bands of the Swan system. A line list has been made available, including observed and calculated line positions, Einstein A coefficients and oscillator strengths (f-values). This list will be useful for astronomers, combustion scientists and materials scientists who utilize {C_2} Swan spectra. Similar work is being carried out for a number of singlet systems of {C_2}, in which a single global fit of positions will be performed and intensities calculated. For NH, a line list is being created for the infrared transitions within the X^3Σ{^-} ground state, including previous observations of rotational lines within v=0-2, and rovibrational lines of the Δv=1 sequence up to v'=6. The intensity calculations use a recently calculated dipole moment function which has been used to calculate the lifetime of the v=1 level, but was unpublished. A line list like that for the {C_2} Swan system will be made available, which will be useful for astronomers investigating NH and nitrogen abundance in cool objects.

  4. Employing Forbidden Transitions as Qubits in a Nuclear Spin-Free Chromium Complex.

    PubMed

    Fataftah, Majed S; Zadrozny, Joseph M; Coste, Scott C; Graham, Michael J; Rogers, Dylan M; Freedman, Danna E

    2016-02-03

    The implementation of quantum computation (QC) would revolutionize scientific fields ranging from encryption to quantum simulation. One intuitive candidate for the smallest unit of a quantum computer, a qubit, is electronic spin. A prominent proposal for QC relies on high-spin magnetic molecules, where multiple transitions between the many MS levels are employed as qubits. Yet, over a decade after the original notion, the exploitation of multiple transitions within a single manifold for QC remains unrealized in these high-spin species due to the challenge of accessing forbidden transitions. To create a proof-of-concept system, we synthesized the novel nuclear spin-free complex [Cr(C3S5)3](3-) with precisely tuned zero-field splitting parameters that create two spectroscopically addressable transitions, with one being a forbidden transition. Pulsed electron paramagnetic resonance (EPR) measurements enabled the investigation of the coherent lifetimes (T2) and quantum control (Rabi oscillations) for two transitions, one allowed and one forbidden, within the S = (3)/2 spin manifold. This investigation represents a step forward in the development of high-spin species as a pathway to scalable QC systems within magnetic molecules.

  5. Investigation of internal bremsstrahlung radiation accompanying forbidden β-decay of 169Er and 170Tm

    NASA Astrophysics Data System (ADS)

    Khalil, E. I.

    2011-06-01

    The internal bremsstrahlung (IB) spectrum accompanying the β-decay of the first forbidden β-transitions of 169Er and 170Tm is studied. The IB was measured using a scintillation γ-spectrometer. It was analyzed by the variable width peeling-off-method, and then corrected by applying the proper corrections. The analyzed and corrected IB spectrum was compared with those calculated according to the original theories of Knipp and Uhlenbeck (1936) as well as of Bloch (1936) (KUB), the coulomb corrected theory of Nilsson (1956), Lewis and Ford (1957), and detour transitions of Ford and Martin (1969). Also, a new trial was carried out by applying the shape correction factor C1 of the first forbidden β-transition suggested by Konopinski and Uhlenbeck (1935, 1941) on the Fermi β-decay theory to the calculated IB based on Nilsson's theory. It is called modified KUB (M.KUB). The experimental results are in a good agreement with the theoretical calculations of forbidden β-transition of Ford and Martin (1969), and M.KUB. It is observed that the Coloumb contribution into IB spectrum is larger for lower β-endpoint energies in case of the sources of same Coulomb charge ( Z) and different β-endpoint energies.

  6. Illusory color mixing upon perceptual fading and filling-in does not result in 'forbidden colors'.

    PubMed

    Hsieh, P-J; Tse, P U

    2006-07-01

    A retinally stabilized object readily undergoes perceptual fading. It is commonly believed that the color of the apparently vanished object is filled in with the color of the background because the features of the filled-in area are determined by features located outside the stabilized boundary. Crane, H. D., & Piantanida, T. P. (1983) (On seeing reddish green and yellowish blue. Science, 221, 1078-1080) reported that the colors that are perceived upon full or partial perceptual fading can be 'forbidden' in the sense that they violate color opponency theory. For example, they claimed that their subjects could perceive "reddish greens" and "yellowish blues." Here we use visual stimuli composed of spatially alternating stripes of two different colors to investigate the characteristics of color mixing during perceptual filling-in, and to determine whether 'forbidden colors' really occur. Our results show that (1) the filled-in color is not solely determined by the background color, but can be the mixture of the background and the foreground color; (2) apparent color mixing can occur even when the two colors are presented to different eyes, implying that color mixing during filling-in is in part a cortical phenomenon; and (3) perceived colors are not 'forbidden colors' at all, but rather intermediate colors.

  7. Observation of forbidden phonons, Fano resonance and dark excitons by resonance Raman scattering in few-layer WS2

    NASA Astrophysics Data System (ADS)

    Tan, Qing-Hai; Sun, Yu-Jia; Liu, Xue-Lu; Zhao, Yanyuan; Xiong, Qihua; Tan, Ping-Heng; Zhang, Jun

    2017-09-01

    The optical properties of the two-dimensional (2D) crystals are dominated by tightly bound electron-hole pairs (excitons) and lattice vibration modes (phonons). The exciton-phonon interaction is fundamentally important to understand the optical properties of 2D materials and thus helps to develop emerging 2D crystal based optoelectronic devices. Here, we presented the excitonic resonant Raman scattering (RRS) spectra of few-layer WS2 excited by 11 lasers lines covered all of A, B and C exciton transition energies at different sample temperatures from 4 to 300 K. As a result, we are not only able to probe the forbidden phonon modes unobserved in ordinary Raman scattering, but also can determine the bright and dark state fine structures of 1s A exciton. In particular, we also observed the quantum interference between low-energy discrete phonon and exciton continuum under resonant excitation. Our works pave a way to understand the exciton-phonon coupling and many-body effects in 2D materials.

  8. A systematic and detailed investigation of radiative rates for forbidden transitions of astrophysical interest in doubly ionized iron peak elements

    NASA Astrophysics Data System (ADS)

    Quinet, Pascal; Fivet, Vanessa; Bautista, Manuel

    2015-08-01

    The knowledge of accurate and reliable atomic data for lowly ionized iron peak elements, from scandium to copper, is of paramount importance for the analysis of the high resolution spectra currently available. The third spectra of several iron group elements have been observed in different galactic sources like Herbig-Haro objects in the Orion Nebula [1] and stars like Eta Carinae [2]. However, forbidden transitions between low-lying metastable levels of doubly ionized species have been little investigated so far and radiative rates for those lines remain sparse or inexistent.In the present contribution, we report on the recent study we have performed concerning the determination of magnetic dipole (M1) and electric quadrupole (E2) transition probabilities in those ions. For the calculations, we have extensively used the pseudo-relativistic Hartree-Fock (HFR) code of Cowan [3] and the central Thomas-Fermi-Dirac potential approximation implemented in AUTOSTRUCTURE [4]. This multi-platform approach allowed us to check the consistency and to assess the accuracy of the results obtained.[1] Mesa-Delgado A. et al., MNRAS 395, 855 (2009)[2] Johansson S. et al., A&A 361, 977 (2000)[3] Cowan R.D., The Theory of Atomic Structure and Spectra, Univ. California Press, Berkeley (1981)[4] Badnell N.R., J. Phys. B: At. Mol. Opt. Phys. 30, 1 (1997)

  9. A survey of Preventive Measures Used and their Impact on Central Line-Associated Bloodstream Infections (CLABSI) in Intensive Care Units (SPIN-BACC)

    PubMed Central

    2013-01-01

    Background The Quebec central line-associated bloodstream infections (CLABSI) in intensive care units (ICUs) Surveillance Program saw a decrease in CLABSI rates in most ICUs. Given the surveillance trends observed in recent years, we aimed to determine what preventive measures have been implemented, if compliance to measures was monitored and its impact on CLABSI incidence rates. Methods All hospitals participating in the Quebec healthcare-associated infections surveillance program (SPIN-BACC – n = 48) received a 77-question survey about preventive measures implemented and monitored in their ICU. The questionnaire was validated for construct, content, face validity, and reliability. We used Poisson regression to measure the association between compliance monitoring to preventive measures and CLABSI rates. Results Forty-two (88%) eligible hospitals completed the survey. Two components from the maximum barrier precautions were used less optimally: cap (88%) and full sterile body drape (71%). Preventive measures reported included daily review of catheter need (79%) and evaluation of insertion site for the presence of inflammation (90%). Two hospitals rewired lines even if an infection was suspected or documented. In adult ICUs, there was a statistically significant greater decrease in CLABSI rates in ICUs that monitored compliance to preventive insertion measures, after adjusting for teaching status and the number of hospital beds (p = 0.036). Conclusions Hospitals participating to the SPIN-BACC program follow recommendations for CLABSI prevention, but only a minority locally monitor their application. Compliance monitoring of preventive measures for catheter insertion was associated with a decrease in CLABSI incidence rates. PMID:24289473

  10. The epidemiology of tick-borne haemoparasites as determined by the reverse line blot hybridization assay in an intensively studied cohort of calves in western Kenya.

    PubMed

    Njiiri, Nyawira E; Bronsvoort, B Mark deC; Collins, Nicola E; Steyn, Helena C; Troskie, Milana; Vorster, Ilse; Thumbi, S M; Sibeko, Kgomotso P; Jennings, Amy; van Wyk, Ilana Conradie; Mbole-Kariuki, Mary; Kiara, Henry; Poole, E Jane; Hanotte, Olivier; Coetzer, Koos; Oosthuizen, Marinda C; Woolhouse, Mark; Toye, Philip

    2015-05-30

    The development of sensitive surveillance technologies using PCR-based detection of microbial DNA, such as the reverse line blot assay, can facilitate the gathering of epidemiological information on tick-borne diseases, which continue to hamper the productivity of livestock in many parts of Africa and elsewhere. We have employed a reverse line blot assay to detect the prevalence of tick-borne parasites in an intensively studied cohort of indigenous calves in western Kenya. The calves were recruited close to birth and monitored for the presence of infectious disease for up to 51 weeks. The final visit samples from 453 calves which survived for the study period were analyzed by RLB. The results indicated high prevalences of Theileria mutans (71.6%), T. velifera (62.8%), Anaplasma sp. Omatjenne (42.7%), A. bovis (39.9%), Theileria sp. (sable) (32.7%), T. parva (12.9%) and T. taurotragi (8.5%), with minor occurrences of eight other haemoparasites. The unexpectedly low prevalence of the pathogenic species Ehrlichia ruminantium was confirmed by a species-specific PCR targeting the pCS20 gene region. Coinfection analyses of the seven most prevalent haemoparasites indicated that they were present as coinfections in over 90% of the cases. The analyses revealed significant associations between several of the Theileria parasites, in particular T. velifera with Theileria sp. sable and T. mutans, and T. parva with T. taurotragi. There was very little coinfection of the two most common Anaplasma species, although they were commonly detected as coinfections with the Theileria parasites. The comparison of reverse line blot and serological results for four haemoparasites (T. parva, T. mutans, A. marginale and B. bigemina) indicated that, except for the mostly benign T. mutans, indigenous cattle seem capable of clearing infections of the three other, pathogenic parasites to below detectable levels. Although the study site was located across four agroecological zones, there was

  11. In-line silica capillary tube all-silica fiber-optic Fabry-Perot interferometric sensor for detecting high intensity focused ultrasound fields.

    PubMed

    Wang, D H; Wang, S J; Jia, P G

    2012-06-01

    Aiming at detecting high intensity focused ultrasound (HIFU) fields, this letter reports on a novel in-line silica capillary tube all-silica fiber-optic Fabry-Perot (ILSCT-ASFP) interferometric sensor fabricated by splicing a commercially available silica capillary tube to two single-mode fibers. The experimental results show that such a novel ILSCT-ASFP interferometric sensor with a cavity length of ∼60.76 μm has an excellent fringe visibility of up to ∼20 dB, and the fringe visibility is still good when the cavity length extends up to ∼1031.07 μm. The measured wavelength-temperature sensitivity of 0.000858 nm/°C shows that the wavelength drift of the fabricated ILSCT-ASFP interferometric sensor towards temperature is extremely low. Meanwhile, the measurement of HIFU fields by this novel sensor is demonstrated, and the experimental results indicate that the signal-to-noise ratio of the sensing system for sensing a 0.93 MHz HIFU field with a pressure of 2.69 MPa in the focus area can reach 42.8 dB. The corresponding noise equivalent pressure is 0.0194 MPa, and the calculated acoustic sensitivity is 65.4 mV/MPa over a 2.5 MHz measurement bandwidth.

  12. The optically thick C III spectrum. 2: Level/term populations and line/multiplet intensities using an improved hybrid model

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1993-01-01

    An improved hybrid level/term calculation is employed to obtain C III level/term populations and line/fractional multiplet intensities over the extended range of electron density 4.0 less than or equal log N(sub e) less than or equal 12.0, for column lengths L ranging from zero (optically thin) to 10(exp 20)/sq cm (moderately optically thick), at electron temperatures T(sub e) approximately 40,000 K(log T(sub e) = 4.6), T(sub e) approximately 63,000 K (log T(sub e) = 4.8), T(sub e) approximately 79,500 K (log T(sub e) = 4.9), and T(sub e) = 100,000 K (log T(sub e) = 5.0). The tabulated results are relevant to the interpretation of space observations obtained over extended spectral ranges by new and planned facilities including the Hopkins Ultraviolet Telescope (HUT) and the Far-Ultraviolet Spectrographic Explorer (FUSE).

  13. Dissecting the High-z Interstellar Medium through Intensity Mapping Cross-correlations

    NASA Astrophysics Data System (ADS)

    Serra, Paolo; Doré, Olivier; Lagache, Guilaine

    2016-12-01

    We explore the detection, with upcoming spectroscopic surveys, of three-dimensional power spectra of emission line fluctuations produced in different phases of the interstellar medium (ISM) by forbidden transitions of ionized carbon [C ii] (157.7 μm), ionized nitrogen [N ii] (121.9 and 205.2 μm), and neutral oxygen [O i] (145.5 μm) at redshift z > 4. These lines are important coolants of both the neutral and the ionized medium, and probe multiple phases of the ISM. In the framework of the halo model, we compute predictions of the three-dimensional power spectra for two different surveys, showing that they have the required sensitivity to detect cross-power spectra between the [C ii] line and both the [O i] line and the [N ii] lines with sufficient signal-to-noise ratio. The importance of cross-correlating multiple lines with the intensity mapping technique is twofold. On the one hand, we will have multiple probes of the different phases of the ISM, which is key to understanding the interplay between energetic sources, and the gas and dust at high redshift. This kind of study will be useful for a next-generation space observatory such as the NASA Far-IR Surveyor, which will probe the global star formation and the ISM of galaxies from the peak of star formation to the epoch of reionization. On the other hand, emission lines from external galaxies are an important foreground when measuring spectral distortions of the cosmic microwave background spectrum with future space-based experiments like PIXIE; measuring fluctuations in the intensity mapping regime will help constrain the mean amplitude of these lines, and will allow us to better handle this important foreground.

  14. A detailed study of the emission lines in the Seyfert 1 nucleus of M81

    NASA Astrophysics Data System (ADS)

    Filippenko, Alexei V.; Sargent, Wallace L. W.

    1988-01-01

    The authors present optical spectra of M81 having moderate resolution (1.6 - 4.5 Å) and exceptionally high signal-to-noise ratios. The broad component of Hα emission first noticed by Peimbert and Torres-Peimbert is easily visible, confirming that M81 harbors an active galactic nucleus (AGN) of the Seyfert 1 type. Prominent forbidden lines are also present. An absorption-line template galaxy, NGC 4339, is used to eliminate the starlight, revealing the pure emission-line spectrum of M81. A detailed analysis of the nuclear narrow-line region is given. It is shown that a wide range of densities is present, making the observed relative intensities consistent with photoionization by dilute, nonstellar radiation. The authors derive the mass of the central object in M81 (≡5×105M_sun;), under the assumption that the widths of the broad permitted lines are induced by gravity. It appears that there have been no changes in the strength of the broad Hα line during the past few years, even though the X-ray flux of M81 has been observed to vary substantially.

  15. [Forbidden anatomy].

    PubMed

    Holck, Per

    2004-12-16

    Since centuries anatomists have used any course of action in order to get hold of material for dissections, and at the same time avoid prosecution for grave robbery, at times the only way to get hold of cadavers. Stealing newly dead people from the churchyards and offering them for sale to anatomical institutions was not uncommon in the 19th century. "Resurrectionists"--as these thieves were called, as they made the dead "alive"--were seen as necessary for the teaching of anatomy in Victorian Britain. In the 1820s a scandal was revealed in Scotland, when it was discovered that some people even committed murder to make money from supplying anatomists with human cadavers. Two men, William Burke and William Hare, became particularly notorious because of their "business" with the celebrated anatomist Robert Knox in Edinburgh.

  16. The Association of State Legal Mandates for Data Submission of Central Line-associated Blood Stream Infections in Neonatal Intensive Care Units with Process and Outcome Measures

    PubMed Central

    Zachariah, Philip; Reagan, Julie; Furuya, E. Yoko; Dick, Andrew; Liu, Hangsheng; Herzig, Carolyn T.A; Pogorzelska-Maziarz, Monika; Stone, Patricia W.; Saiman, Lisa

    2014-01-01

    Objective To determine the association between state legal mandates for data submission of central line-associated blood stream infections (CLABSIs) in neonatal intensive care units (NICUs) with process/outcome measures. Design Cross-sectional study. Participants National sample of level II/III and III NICUs participating in National Healthcare Safety Network (NHSN) surveillance. Methods State mandates for data submission of CLABSIs in NICUs in place by 2011 were compiled and verified with state healthcare-associated infection coordinators. A web-based survey of infection control departments in October 2011 assessed CLABSI prevention practices i.e. compliance with checklist and bundle components (process measures) in ICUs including NICUs. Corresponding 2011 NHSN NICU CLABSI rates (outcome measures) were used to calculate Standardized Infection Ratios (SIR). The association between mandates and process/outcome measures was assessed by multivariable logistic regression. Results Among 190 study NICUs, 107 (56.3%) NICUs were located in states with mandates, with mandates in place for 3 or more years for half. More NICUs in states with mandates reported ≥95% compliance to at least one CLABSI prevention practice (52.3% – 66.4%) than NICUs in states without mandates (28.9% – 48.2%). Mandates were predictors of ≥95% compliance with all practices (OR 2.8; 95% CI 1.4–6.1). NICUs in states with mandates reported lower mean CLABSI rates in the <750gm birth-weight group (2.4 vs. 5.7 CLABSIs/1000 CL-days) but not in others. Mandates were not associated with SIR <1. Conclusions State mandates for NICU CLABSI data submission were significantly associated with ≥95% compliance with CLABSI prevention practices but not with lower CLABSI rates. PMID:25111921

  17. Central line-associated bloodstream infection in hospitalized children with peripherally inserted central venous catheters: extending risk analyses outside the intensive care unit.

    PubMed

    Advani, Sonali; Reich, Nicholas G; Sengupta, Arnab; Gosey, Leslie; Milstone, Aaron M

    2011-05-01

    Increasingly, peripherally inserted central venous catheters (PICCs) are placed for prolonged intravenous access. Few data exist regarding risk factors for central line-associated bloodstream infection (CLABSI) complicating PICCs in hospitalized children, especially children hospitalized outside the intensive care unit (ICU). We identified all children with a PICC inserted at The Johns Hopkins Hospital (Baltimore, MD) from 1 January 2003 through 31 December 2009 and used Poisson regression models to identify risk factors for PICC-associated CLABSIs. A total of 2592 PICCs were placed in 1819 children. One hundred sixteen CLABSIs occurred over 44,972 catheter-days (incidence rate [IR], 2.58 cases per 1000 catheter-days; 95% confidence interval [CI], 2.07-3.00 cases per 1000 catheter-days). Independent predictors of CLABSI in the entire cohort included PICC dwell time of > 21 days (IR ratio [IRR], 1.53; 95% CI, 1.05-2.26), parenteral nutrition as indication for insertion (IRR, 2.24; 95% CI, 1.31-3.84), prior PICC-associated CLABSI (IRR, 2.48; 95% CI, 1.18-5.25), underlying metabolic condition (IRR, 2.07; 95% CI, 1.14-3.74), and pediatric ICU exposure during hospitalization (IRR, 1.80; 95% CI, 1.18-2.75). Risk factors for CLABSI in children without PICU exposure included younger age, underlying malignancy and metabolic conditions, PICCs inserted in the lower extremity, and a prior PICC-associated CLABSI. Prolonged catheter dwell time, pediatric ICU exposure, and administration of parenteral nutrition as the indication for PICC insertion are important predictors of PICC-associated CLABSI in hospitalized children. A careful assessment of these risk factors may be important for future success in preventing CLABSIs in hospitalized children with PICCs.

  18. The response of the inductively coupled argon plasma to solvent plasma load: spatially resolved maps of electron density obtained from the intensity of one argon line

    NASA Astrophysics Data System (ADS)

    Weir, D. G. J.; Blades, M. W.

    1994-12-01

    A survey of spatially resolved electron number density ( ne) in the tail cone of the inductively coupled argon plasma (ICAP) is presented: all of the results of the survey have been radially inverted by numerical, asymmetric Abel inversion. The survey extends over the entire volume of the plasma beyond the exit of the ICAP torch; It extends over distances of z = 5-25 mm downstream from the induction coil, and over radial distances of ± 8 mm from the discharge axis. The survey also explores a range of inner argon flow rates ( QIN), solvent plasma load ( Qspl) and r.f. power: moreover, it explores loading by water, methanol and chloroform. Throughout the survey, ne was determined from the intensity of one, optically thin argon line, by a method which assumes that the atomic state distribution function (ASDF) for argon lies close to local thermal equilibrium (LTE). The validity of this assumption is reviewed. Also examined are the discrepancies between ne from this method and ne from Stark broadening measurements. With the error taken into account, the results of the survey reveal how time averaged values of ne in the ICAP respond over an extensive, previously unexplored range of experimental parameters. Moreover, the spatial information lends insight into how the thermal conditions and the transport of energy respond. Overall, the response may be described in terms of energy consumption along the axial channel and thermal pinch within the induction region. The predominating effect depends on the solvent plasma load, the solvent composition, the robustness of the discharge, and the distribution of solvent material over the argon stream.

  19. Evaluating application of the National Healthcare Safety Network central line-associated bloodstream infection surveillance definition: a survey of pediatric intensive care and hematology/oncology units.

    PubMed

    Gaur, Aditya H; Miller, Marlene R; Gao, Cuilan; Rosenberg, Carol; Morrell, Gloria C; Coffin, Susan E; Huskins, W Charles

    2013-07-01

    To evaluate the application of the National Healthcare Safety Network (NHSN) central line-associated bloodstream infection (CLABSI) definition in pediatric intensive care units (PICUs) and pediatric hematology/oncology units (PHOUs) participating in a multicenter quality improvement collaborative to reduce CLABSIs; to identify sources of variability in the application of the definition. Online survey using 18 standardized case scenarios. Each described a positive blood culture in a patient and required a yes- or-no answer to the question "Is this a CLABSI?" NHSN staff responses were the reference standard. Sixty-five US PICUs and PHOUs. Staff who routinely adjudicate CLABSIs using NHSN definitions. Sixty responses were received from 58 (89%) of 65 institutions; 78% of respondents were infection preventionists, infection control officers, or infectious disease physicians. Responses matched those of NHSN staff for 78% of questions. The mean (SE) percentage of concurring answers did not differ for scenarios evaluating application of 1 of the 3 criteria ("known pathogen," 78% [1.7%]; "skin contaminant, >1 year of age," 76% [SE, 2.5%]; "skin contaminant, ≤1 year of age," 81% [3.8%]; [Formula: see text]). The mean percentage of concurring answers was lower for scenarios requiring respondents to determine whether a CLABSI was present or incubating on admission (64% [4.6%]; [Formula: see text]) or to distinguish between primary and secondary bacteremia (65% [2.5%]; [Formula: see text]). The accuracy of application of the CLABSI definition was suboptimal. Efforts to reduce variability in identifying CLABSIs that are present or incubating on admission and in distinguishing primary from secondary bloodstream infection are needed.

  20. Electron Impact Excitation of Forbidden and Allowed Transitions in O(II)

    NASA Technical Reports Server (NTRS)

    Tayal, S. S.

    2006-01-01

    The B-spline R-matrix method is used to investigate the electron impact excitation of forbidden and allowed transitions in singly ionized oxygen. The relativistic effects have been incorporated in the Breit-Pauli Hamiltonian. Flexible non-orthogonal sets of radial functions are used to obtain accurate target description and to represent the scattering functions. The 47 fine-structure levels of the 2s(sup 2)2p(sup 3), 2s2p(sup 4), 2s(sup 2)2p(sup 2)3s, 2s(sup 2)2p(sup 2)3p and 2s(sup 2)2p(sup 2)3d configurations have been included in the scattering calculation. A calculation with 62 levels in the close-coupling expansion using the Breit-Pauli R-matrix (BPRM) method with orthogonal radial functions has also been carried out to check electron correlation, relativistic and channel coupling effects. The present results are in good agreement with the previous 16-level BPRM calculation by Montenegro et a1 (2006 J. Phys. B: At. Mol. Opt. Phys. 39 1863-77) for the forbidden transitions, but differ from the 21-level BPRM calculation by McLaughlin and Bell (1998 J. Phys. B: At. Mol. Opt. Phys. 31 4317-29). Our cross sections for the first forbidden (sup 4)S(sup o)-(sup 2)D(sup o)and resonance (sup 4)S(sup o)-2s(sup 2)p(sup 4) (sup 4)P transitions are in reasonably good agreement with the electron energy-loss and merged-beams experiment.

  1. Electron Impact Excitation of Forbidden and Allowed Transitions in O(II)

    NASA Technical Reports Server (NTRS)

    Tayal, S. S.

    2006-01-01

    The B-spline R-matrix method is used to investigate the electron impact excitation of forbidden and allowed transitions in singly ionized oxygen. The relativistic effects have been incorporated in the Breit-Pauli Hamiltonian. Flexible non-orthogonal sets of radial functions are used to obtain accurate target description and to represent the scattering functions. The 47 fine-structure levels of the 2s(sup 2)2p(sup 3), 2s2p(sup 4), 2s(sup 2)2p(sup 2)3s, 2s(sup 2)2p(sup 2)3p and 2s(sup 2)2p(sup 2)3d configurations have been included in the scattering calculation. A calculation with 62 levels in the close-coupling expansion using the Breit-Pauli R-matrix (BPRM) method with orthogonal radial functions has also been carried out to check electron correlation, relativistic and channel coupling effects. The present results are in good agreement with the previous 16-level BPRM calculation by Montenegro et a1 (2006 J. Phys. B: At. Mol. Opt. Phys. 39 1863-77) for the forbidden transitions, but differ from the 21-level BPRM calculation by McLaughlin and Bell (1998 J. Phys. B: At. Mol. Opt. Phys. 31 4317-29). Our cross sections for the first forbidden (sup 4)S(sup o)-(sup 2)D(sup o)and resonance (sup 4)S(sup o)-2s(sup 2)p(sup 4) (sup 4)P transitions are in reasonably good agreement with the electron energy-loss and merged-beams experiment.

  2. Existence of a light intensity threshold for photoconversion processes

    SciTech Connect

    Gregg, B.A.; Nozik, A.J. )

    1993-12-23

    Two models of the mechanism of photoinduced electron transfer at semiconductor surfaces have long been differentiated by their prediction, or their denial, of the existence of a light intensity threshold for fuel-forming photoconversion processes. We attempt to clarify this problem by making a distinction between two possible types of thresholds: a threshold for incipient product formation and a threshold for product formation in a specified state, such as its standard state. A light intensity threshold for incipient product formation appears to be forbidden by molecular electron-transfer theory and has apparently never been observed. Conversely, a light intensity threshold for product formation in its standard state must always occur, simply because the product concentration must first build up from its equilibrium value to its standard-state value. Since the former threshold is forbidden, while the latter is unavoidable, the existence of a threshold cannot be used to distinguish between the models. 20 refs.

  3. Theoretical investigation on dye sensitizer solar cell: Spin-forbidden transition

    SciTech Connect

    Imamura, Yutaka

    2015-12-31

    We studied spin-forbidden transitions of metal polypyridyl sensitizers by two-component relativistic time-dependent density functional theory with the spin-orbit interaction based on Tamm-Dancoff approximation. The singlet-to-triplet transition, which is assigned to a metal-to-ligand charge-transfer type excitation, appears for a phosphine-coordinated Ru(II), DX1. Absorption spectra of the modified DX1 molecules, whose Ru is replaced with Fe and Os, were also calculated for examining the effects of metals on the spin-orbit interaction.

  4. Pseudospin Symmetry and Forbidden Magnetic Dipole and Gamow-Teller Transitions

    NASA Astrophysics Data System (ADS)

    Ginocchio, Joseph

    1999-10-01

    Recently it has been shown that pseudospin symmetry has its origins in a relativistic symmetry of the Dirac Hamiltonian[1]. Using this symmetry we relate single - nucleon relativistic magnetic moments of states in a pseudospin doublet to the relativistic magnetic dipole transitions between the states in the doublet, and we relate single - nucleon relativistic Gamow - Teller transitions within states in the doublet. We apply these relationships to the Gamow - Teller transitions from ^39Ca to its mirror nucleus ^39K [2] and to the systematics of forbidden magnetic dipole transitions. 1. J. N. Ginocchio and A. Leviatan Phys. Lett. B 425, 1 (1998). 2. J. N. Ginocchio Phys. Rev. C 59, 2487 (1999).

  5. Attenuation of Lamb waves in the vicinity of a forbidden band in a phononic crystal.

    PubMed

    Bavencoffe, Maxime; Hladky-Hennion, Anne-Christine; Morvan, Bruno; Izbicki, Jean-Louis

    2009-09-01

    When a Lamb wave propagates on a plate engraved by a periodic grating, it may exhibit attenuation. This attenuation is related to a coupling of this incident mode with other propagating modes. As the propagation takes place in a periodic medium, the dispersion curves of the modes are of interest because they exhibit passbands and stopbands related to the geometry of the waveguide. The goal of this work is to quantitatively establish the relation between the value of the attenuation of the propagating waves and the width of the forbidden bands appearing inside the Brillouin zone. This study is performed by using a finite element method (ATILA code).

  6. Search for rare and forbidden decays of the charmed meson D+

    NASA Astrophysics Data System (ADS)

    Frabetti, P. L.; Cheung, H. W. K.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Johns, W. E.; Nehring, M. S.; Vaandering, E. W.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garbincius, P. H.; Garren, L.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Vittone, M.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Cawlfield, C.; Culbertson, R.; Gardner, R. W.; Greene, R.; Rahimi, A.; Wiss, J.; Alimonti, G.; Bellini, G.; Boschini, M.; Brambilla, D.; Caccianiga, B.; Cinquini, L.; di Corato, M.; Dini, P.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Milazzo, L.; Moroni, L.; Pedrini, D.; Perasso, L.; Prelz, F.; Sala, A.; Sala, S.; Torretta, D.; Buchholz, D.; Claes, D.; Gobbi, B.; O'Reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Puseljic, D. L.; Ruchti, R. C.; Shephard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Bonomi, G.; Castoldi, C.; Gianini, G.; Merlo, M.; Ratti, S. P.; Riccardi, C.; Viola, L.; Vitulo, P.; Lopez, A.; Mendez, L.; Montiel, E.; Olaya, D.; Ramirez, E.; Rivera, C.; Zhang, Y.; Grim, G. P.; Link, J. M.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Cao, J.; Hosack, M.; Hughes, J.; Sheldon, P. D.; Davenport, F.; Danyo, K.; Handler, T.; Cheon, B. G.; Chung, Y. S.; Kang, J. S.; Kim, K. Y.; Lee, K. B.; Myung, S. S.

    1997-02-01

    We report on the results of a search for fourteen flavor changing neutral current, lepton number violating, or lepton family number violating decays of the charmed meson D+ in the large charm sample recorded by the Fermilab photoproduction experiment E687. No evidence is seen for these rare and standard-model-forbidden decays, of the form D+ ->h+/- l-/+l+ (with h = π, K and l = e, μ) we determine 90% confidence level upper limits on their absolute branching fractions in the range (9-20) × 10-5.

  7. Electronically forbidden (5σu-->kσu) photoionization of CS2: Mode-specific electronic-vibrational coupling

    NASA Astrophysics Data System (ADS)

    Rathbone, G. J.; Poliakoff, E. D.; Bozek, John D.; Lucchese, R. R.

    2005-02-01

    Vibrationally resolved photoelectron spectroscopy of the CS2+(BΣu +2) state is used to show how nontotally symmetric vibrations "activate" a forbidden electronic transition in the photoionization continuum, specifically, a 5σu→kσu shape resonance, that would be inaccessible in the absence of a symmetry breaking vibration. This electronic channel is forbidden owing to inversion symmetry selection rules, but it can be accessed when a nonsymmetric vibration is excited, such as bending or antisymmetric stretching. Photoelectron spectra are acquired for photon energies 17⩽hν⩽72eV, and it is observed that the forbidden vibrational transitions are selectively enhanced in the region of a symmetry-forbidden continuum shape resonance centered at hν ≈42eV. Schwinger variational calculations are performed to analyze the data, and the theoretical analysis demonstrates that the observed forbidden transitions are due to photoelectron-mediated vibronic coupling, rather than interchannel Herzberg-Teller mixing. We observe and explain the counterintuitive result that some vibrational branching ratios vary strongly with energy in the region of the resonance, even though the resonance position and width are not appreciably influenced by geometry changes that correspond to the affected vibrations. In addition, we find that another resonant channel, 5σu→kπg, influences the symmetric stretch branching ratio. All of the observed effects can be understood within the framework of the Chase adiabatic approximation, i.e., the Born-Oppenheimer approximation applied to photoionization.

  8. Prediction of Forbidden Ultraviolet and Visible Emissions in Comet 67P/Churyumov-Gerasimenko

    NASA Astrophysics Data System (ADS)

    Raghuram, Susarla; Bhardwaj, Anil; Galand, Marina

    2016-02-01

    Remote observation of spectroscopic emissions is a potential tool for the identification and quantification of various species in comets. The CO Cameron band (to trace CO2) and atomic oxygen emissions (to trace H2O and/or CO2, CO) have been used to probe neutral composition in the cometary coma. Using a coupled-chemistry-emission model, various excitation processes controlling the CO Cameron band and different atomic oxygen and atomic carbon emissions have been modeled in comet 67P/Churyumov-Gerasimenko at 1.29 AU (perihelion) and at 3 AU heliocentric distances, which is being explored by ESA's Rosetta mission. The intensities of the CO Cameron band, atomic oxygen, and atomic carbon emission lines as a function of projected distance are calculated for different CO and CO2 volume mixing ratios relative to water. Contributions of different excitation processes controlling these emissions are quantified. We assess how CO2 and/or CO volume mixing ratios with respect to H2O can be derived based on the observed intensities of the CO Cameron band, atomic oxygen, and atomic carbon emission lines. The results presented in this work serve as baseline calculations to understand the behavior of low out-gassing cometary coma and compare them with the higher gas production rate cases (e.g., comet Halley). Quantitative analysis of different excitation processes governing the spectroscopic emissions is essential to study the chemistry of inner coma and to derive neutral gas composition.

  9. Incidence, case-fatality rate and clinical pattern of firearm injuries in two cities where arm owning is forbidden.

    PubMed

    Bahebeck, Jean; Atangana, Rene; Mboudou, Emile; Nonga, Bernadette Ngo; Sosso, Maurice; Malonga, Eimo

    2005-06-01

    To review firearm injuries in five hospitals of Douala and Yaounde, both towns of Cameroon, a Sub-Saharan African country where ownership of firearm is forbidden. This was a retrospective investigation carried out within the period January 1998 to December 2002. Records of the mortuaries, the emergency departments, the intensive care units, the operating rooms and the surgical units were all analysed to identify any injury caused by firearm. Our gold standard was any individual with a clear diagnosis of firearm injury, as determined by a medical doctor. 286 firearm injuries were found; 1.14 cases per 100,000 per year. 66% of cases were due to civilian assaults, 20% to armed forces, 8% to hunting accidents and 6% to accidental handling. There was no case of suicide or of shooting from a relative. The type of weapon was unknown in 31% of cases, it was a hand gun in 36%, a hunting type in 21% and an assault rifle in 12%. The mean age of victims was 33 years and the male:female ratio 5.5:1. The site of injury was unknown in 2%; the head in 6%, the chest in 12%, the abdomen in 31%, the extremities in 46%, the spine in 1% and multiple in 2%. The case fatality rate was 12.58%, and the victims were mainly criminals killed by armed forces assaults; the same ratio of survivors developed late complications. The incidence of firearm injuries in the two largest cities of Cameroon is five to fifty times lower than in many other towns, especially in Western countries. This may be due at least partially, to the current legislation on the ownership of firearm which is very restrictive in this country. Some efforts are however needed to reduce illegal access to weapons and to educate hunters on the safe handling of their gun.

  10. Plant species forbidden in health food and their toxic constituents, toxicology and detoxification.

    PubMed

    Xu, Xi-Lin; Shang, Yu; Jiang, Jian-Guo

    2016-02-01

    Many plants with pharmacological efficacies are widely used as ingredients in so-called "health foods", but many of them are toxic. In order to ensure the safety of "health food", the Chinese Ministry of Health has listed 59 materials that are forbidden from being used in health food and are called health food forbidden species (HFFS). This review focuses on 47 plants among the HFFS to discuss research regarding their pharmacology, toxicology, and detoxification methods. According to the literature published in the last 2 decades, the main constituents and the pharmacology of such plants are described here, especially their toxic constituents and toxicology. The toxicity mechanisms of several typical toxic components from the 47 plants are outlined and some effective detoxification methods are introduced. Although all HFFS are poisonous, they are considered to be useful in the treatment of many diseases. How to keep their pharmacological effects and at the same time decrease their toxicity is a great challenge. In the future, more attention should be paid to the application of modern science and technology in the exploration of the toxicology and detoxification of HFFS.

  11. Forbidden phonon: Dynamical signature of bond symmetry breaking in the iron chalcogenides

    NASA Astrophysics Data System (ADS)

    Fobes, David M.; Zaliznyak, Igor A.; Tranquada, John M.; Xu, Zhijun; Gu, Genda; He, Xu-Gang; Ku, Wei; Zhao, Yang; Matsuda, Masaaki; Garlea, V. Ovidiu; Winn, Barry

    2016-09-01

    Investigation of the inelastic neutron scattering spectra in Fe1 +yTe1 -xSex near a signature wave vector Q =(1 ,0 ,0 ) for the bond-order wave (BOW) formation of parent compound Fe1 +yTe [D. Fobes et al., Phys. Rev. Lett. 112, 187202 (2014), 10.1103/PhysRevLett.112.187202] reveals an acoustic-phonon-like dispersion present in all structural phases. While a structural Bragg peak accompanies the mode in the low-temperature phase of Fe1 +yTe , it is absent in the high-temperature tetragonal phase, where Bragg scattering at this Q is forbidden by symmetry. Notably, this mode is also observed in superconducting FeTe0.55Se0.45 , where structural and magnetic transitions are suppressed, and no BOW has been observed. The presence of this "forbidden" phonon indicates that the lattice symmetry is dynamically or locally broken by magneto-orbital BOW fluctuations, which are strongly coupled to lattice in these materials.

  12. Age and violent-content labels make video games forbidden fruits for youth.

    PubMed

    Bijvank, Marije Nije; Konijn, Elly A; Bushman, Brad J; Roelofsma, Peter H M P

    2009-03-01

    To protect minors from exposure to video games with objectionable content (eg, violence and sex), the Pan European Game Information developed a classification system for video games (eg, 18+). We tested the hypothesis that this classification system may actually increase the attractiveness of games for children younger than the age rating. Participants were 310 Dutch youth. The design was a 3 (age group: 7-8, 12-13, and 16-17 years) x 2 (participant gender) x 7 (label: 7+, 12+, 16+, 18+, violence, no violence, or no label control) x 2 (game description: violent or nonviolent) mixed factorial. The first 2 factors were between subjects, whereas the last 2 factors were within subjects. Three personality traits (ie, reactance, trait aggressiveness, and sensation seeking) were also included in the analyses. Participants read fictitious video game descriptions and rated how much they wanted to play each game. Results revealed that restrictive age labels and violent-content labels increased the attractiveness of video games for all of the age groups (even 7- to 8-year-olds and girls). Although the Pan European Game Information system was developed to protect youth from objectionable content, this system actually makes such games forbidden fruits. Pediatricians should be aware of this forbidden-fruit effect, because video games with objectionable content can have harmful effects on children and adolescents.

  13. Implications of two-component dark matter induced by forbidden channels and thermal freeze-out

    NASA Astrophysics Data System (ADS)

    Aoki, Mayumi; Toma, Takashi

    2017-01-01

    We consider a model of two-component dark matter based on a hidden U(1)D symmetry, in which relic densities of the dark matter are determined by forbidden channels and thermal freeze-out. The hidden U(1)D symmetry is spontaneously broken to a residual Bbb Z4 symmetry, and the lightest Bbb Z4 charged particle can be a dark matter candidate. Moreover, depending on the mass hierarchy in the dark sector, we have two-component dark matter. We show that the relic density of the lighter dark matter component can be determined by forbidden annihilation channels which require larger couplings compared to the normal freeze-out mechanism. As a result, a large self-interaction of the lighter dark matter component can be induced, which may solve small scale problems of ΛCDM model. On the other hand, the heavier dark matter component is produced by normal freeze-out mechanism. We find that interesting implications emerge between the two dark matter components in this framework. We explore detectabilities of these dark matter particles and show some parameter space can be tested by the SHiP experiment.

  14. Beyond neutral and forbidden links: morphological matches and the assembly of mutualistic hawkmoth-plant networks.

    PubMed

    Sazatornil, Federico D; Moré, Marcela; Benitez-Vieyra, Santiago; Cocucci, Andrea A; Kitching, Ian J; Schlumpberger, Boris O; Oliveira, Paulo E; Sazima, Marlies; Amorim, Felipe W

    2016-11-01

    A major challenge in evolutionary ecology is to understand how co-evolutionary processes shape patterns of interactions between species at community level. Pollination of flowers with long corolla tubes by long-tongued hawkmoths has been invoked as a showcase model of co-evolution. Recently, optimal foraging models have predicted that there might be a close association between mouthparts' length and the corolla depth of the visited flowers, thus favouring trait convergence and specialization at community level. Here, we assessed whether hawkmoths more frequently pollinate plants with floral tube lengths similar to their proboscis lengths (morphological match hypothesis) against abundance-based processes (neutral hypothesis) and ecological trait mismatches constraints (forbidden links hypothesis), and how these processes structure hawkmoth-plant mutualistic networks from five communities in four biogeographical regions of South America. We found convergence in morphological traits across the five communities and that the distribution of morphological differences between hawkmoths and plants is consistent with expectations under the morphological match hypothesis in three of the five communities. In the two remaining communities, which are ecotones between two distinct biogeographical areas, interactions are better predicted by the neutral hypothesis. Our findings are consistent with the idea that diffuse co-evolution drives the evolution of extremely long proboscises and flower tubes, and highlight the importance of morphological traits, beyond the forbidden links hypothesis, in structuring interactions between mutualistic partners, revealing that the role of niche-based processes can be much more complex than previously known.

  15. Understanding the rate of spin-forbidden thermolysis of HN3 and CH3N3

    NASA Astrophysics Data System (ADS)

    Besora, Maria; Harvey, Jeremy Noel

    2008-07-01

    The pyrolysis of the simplest azides HN3 and CH3N3 has been studied computationally. Nitrogen extrusion leads to the production of NH or CH3N. The azides have singlet ground states but the nitrenes CH3N and NH have triplet ground states. The competition between spin-allowed decomposition to the excited state singlet nitrenes and the spin-forbidden N2 loss is explored using accurate electronic structure methods (CASSCF/cc-pVTZ and MR-AQCC/cc-pVTZ) as well as statistical rate theories. Nonadiabatic rate theories are used for the dissociation leading to the triplet nitrenes. For HN3, 3NH formation is predicted to dominate at low energy, and the calculated rate constant agrees very well with energy-resolved experimental measurements. Under thermal conditions, however, the singlet and triplet pathways are predicted to occur competitively, with the spin-allowed product increasingly favored at higher temperatures. For CH3N3 thermolysis, spin-allowed dissociation to form 1CH3N should largely dominate at all temperatures, with spin-forbidden formation of 3CH3N almost negligible. Singlet methyl nitrene is very unstable and should rearrange to CH2NH immediately upon formation, and the latter species may lose H2 competitively with vibrational cooling, depending on temperature and pressure.

  16. Understanding the rate of spin-forbidden thermolysis of HN3 and CH3N3.

    PubMed

    Besora, Maria; Harvey, Jeremy Noel

    2008-07-28

    The pyrolysis of the simplest azides HN(3) and CH(3)N(3) has been studied computationally. Nitrogen extrusion leads to the production of NH or CH(3)N. The azides have singlet ground states but the nitrenes CH(3)N and NH have triplet ground states. The competition between spin-allowed decomposition to the excited state singlet nitrenes and the spin-forbidden N(2) loss is explored using accurate electronic structure methods (CASSCF/cc-pVTZ and MR-AQCC/cc-pVTZ) as well as statistical rate theories. Nonadiabatic rate theories are used for the dissociation leading to the triplet nitrenes. For HN(3), (3)NH formation is predicted to dominate at low energy, and the calculated rate constant agrees very well with energy-resolved experimental measurements. Under thermal conditions, however, the singlet and triplet pathways are predicted to occur competitively, with the spin-allowed product increasingly favored at higher temperatures. For CH(3)N(3) thermolysis, spin-allowed dissociation to form (1)CH(3)N should largely dominate at all temperatures, with spin-forbidden formation of (3)CH(3)N almost negligible. Singlet methyl nitrene is very unstable and should rearrange to CH(2)NH immediately upon formation, and the latter species may lose H(2) competitively with vibrational cooling, depending on temperature and pressure.

  17. A multicenter quasi-experimental study: impact of a central line infection control program using auditing and performance feedback in five Belgian intensive care units.

    PubMed

    Cherifi, Soraya; Gerard, Michele; Arias, Sylvie; Byl, Baudouin

    2013-12-05

    We analyzed the impact associated with an intervention based on process control and performance feedback to decrease central line-associated bloodstream infection (CLABSI) rates.This study was conducted from March 2011 to September 2012 in five adult intensive care units (ICU) located in two Belgian tertiary hospitals A and B, with a total of 53 beds. This study was divided in three phases: P1 (baseline), P2 (intervention) and P3 (post intervention).During P2, external monitoring of five central venous catheters (CVC) care critical processes and monthly reporting (meetings and feedbacks reports posted) of performance indicators (CLABSI rate, CVC utilization ratio, compliance rate with each care process, and insertion site) to ICU workers were performed. The external monitoring of process measures was assessed by the same trained research nurse.A Poisson regression analysis was used to compare CLABSI incidence density rate per phase. Statistical significance was achieved with 2-sided p-value of <0.05. For the analysis, we separated the five ICU in hospital A and B when appropriate. Significantly improved total mean compliance was achieved for hand hygiene, CVC handling and CVC dressing. CLABSI rate declined from 4.00 (95% confidence interval (CI): 1.94-6.06) to 1.81 (0.46-3.17) per 1,000 CVC-days in P2 with an incidence rate ratio (IRR) of 0.49 (0.24-0.98, p = 0.043). A better response was observed in hospital A where the nurse participation at the monthly meeting was significantly higher than in hospital B (p < 0.001) as the percentage of feedbacks reports posted in ICU (p < 0.001). The decline in the CLABSI rate observed during P2 in comparison with P1 was independent of the insertion site (femoral or non-femoral; p = 0.054). The overall CLABSI rate increased to 2.73 (1.17-4.29) per 1,000 CVC-days with IRR of 0.67 (0.36-1.26, p = 0.212) in P3 compared to P1, but a high nursing turnover was observed in both hospitals. Our intervention focused on external auditing

  18. Optimizing TaO{sub x} memristor performance and consistency within the reactive sputtering “forbidden region”

    SciTech Connect

    Lohn, Andrew J.; Stevens, James E.; Mickel, Patrick R.; Marinella, Matthew J.

    2013-08-05

    Standard deposition processes for depositing ReRAM oxides utilize mass flow of reactive gas to control stoichiometry and have difficulty depositing a precisely defined sub-stoichiometry within a “forbidden region” where film properties are discontinuous with mass flow. We show that by maintaining partial pressure within this discontinuous “forbidden region,” instead of by maintaining mass flow, we can optimize tantalum oxide device properties and reduce or eliminate the electroforming step. We also show that defining the partial pressure set point as a fraction of the “forbidden region” instead of as an absolute value can be used to improve wafer-to-wafer consistency with minimal recalibration efforts.

  19. The Emission-Line Spectrum of KUG 1031+398 and the Intermediate Line Region Controversy

    NASA Astrophysics Data System (ADS)

    Gonçalves, A. C.; Véron, P.; Véron-Cetty, M.-P.

    We present results based on the analysis of optical spectra of the Narrow-Line Seyfert 1 (NLS1) galaxy KUG 1031+398, for which evidence was reported of a line-emitting region "intermediate" (both in terms of velocity and density) between the conventional Broad and Narrow Line Regions (BLR and NLR, respectively). From our observations and modeling of the spectra, we get a consistent decomposition of the line profiles into four components: an extended H II region with unresolved lines, two distinct Seyfert-type clouds identified with the NLR, and a relatively narrow "broad line" component emitting only Balmer lines but no forbidden lines. Therefore, although we find this object to be exceptional in having line-emission from the BLR with almost the same width as the narrow lines, our interpretation of the data does not support the existence of an "intermediate" line region (ILR).

  20. Electron-impact excitation of Ni II. Collision strengths and effective collision strengths for low-lying fine-structure forbidden transitions

    NASA Astrophysics Data System (ADS)

    Cassidy, C. M.; Ramsbottom, C. A.; Scott, M. P.; Burke, P. G.

    2010-04-01

    Context. Considerable demand exists for electron excitation data for ion{Ni}{ii}, since lines from this abundant ion are observed in a wide variety of laboratory and astrophysical spectra. The accurate theoretical determination of these data can present a significant challenge however, due to complications arising from the presence of an open 3d-shell in the description of the target ion. Aims: In this work we present collision strengths and Maxwellian averaged effective collision strengths for the electron-impact excitation of ion{Ni}{ii}. Attention is concentrated on the 153 forbidden fine-structure transitions between the energetically lowest 18 levels of ion{Ni}{ii}. Effective collision strengths have been evaluated at 27 individual electron temperatures ranging from 30-100 000 K. To our knowledge this is the most extensive theoretical collisional study carried out on this ion to date. Methods: The parallel R-matrix package RMATRX II has recently been extended to allow for the inclusion of relativistic effects. This suite of codes has been utilised in the present work in conjunction with PSTGF to evaluate collision strengths and effective collision strengths for all of the low-lying forbidden fine-structure transitions. The following basis configurations were included in the target model - 3d9, 3d84s, 3d84p, 3d74s2 and 3d74s4p - giving rise to a sophisticated 295 jj-level, 1930 coupled channel scattering problem. Results: Comprehensive comparisons are made between the present collisional data and those obtained from earlier theoretical evaluations. While the effective collision strengths agree well for some transitions, significant discrepancies exist for others. Table 2 is only 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?J/A+A/513/A55

  1. Contributions of unique first-forbidden transitions to two-neutrino double-β-decay half-lives

    NASA Astrophysics Data System (ADS)

    Civitarese, O.; Suhonen, J.

    1996-02-01

    The two-neutrino double-β-decay transition of 76Ge to the ground state of 76Se is calculated using a realistic proton-neutron force and including unique first-forbidden single-β-decay transitions to virtual 2 - intermediate states. The corresponding nuclear matrix elements are computed by using the proton-neutron quasiparticle random-phase approximation (pn-QRPA). From the results of the present study it is concluded that the inclusion of virtual unique first-forbidden transitions, as possible "new" steps contributing to the half-life of the two-neutrino double-β-decay mode, can be disregarded.

  2. Infrared line measurements and the abundance of sulfur in planetary nebulae

    NASA Technical Reports Server (NTRS)

    Dinerstein, H. L.

    1980-01-01

    Ionic abundances of S(+), S(++), and S(+3) relative to hydrogen are determined for 12 planetary nebulae from observations of the S II forbidden lines at 6716 and 6731 A, the S III forbidden line at 9531 A, the S IV forbidden line at 10.5 microns, and P delta 10049 A. The derived total abundances are insensitive to electron density and electron temperature and are found to vary by no more than 30% in the sample; unlike previous determinations, there is no correlation of the abundance with the degree of ionization. The mean elemental abundance for these objects is S/H = 2.1 plus or minus 0.6 x 10 to the -5th, which is, within the measurement errors, the same as the solar value and the abundance in the present interstellar medium as represented by the H II regions K3-50 and Orion.

  3. PREDICTION OF FORBIDDEN ULTRAVIOLET AND VISIBLE EMISSIONS IN COMET 67P/CHURYUMOV–GERASIMENKO

    SciTech Connect

    Raghuram, Susarla; Galand, Marina; Bhardwaj, Anil

    2016-02-20

    Remote observation of spectroscopic emissions is a potential tool for the identification and quantification of various species in comets. The CO Cameron band (to trace CO{sub 2}) and atomic oxygen emissions (to trace H{sub 2}O and/or CO{sub 2}, CO) have been used to probe neutral composition in the cometary coma. Using a coupled-chemistry-emission model, various excitation processes controlling the CO Cameron band and different atomic oxygen and atomic carbon emissions have been modeled in comet 67P/Churyumov–Gerasimenko at 1.29 AU (perihelion) and at 3 AU heliocentric distances, which is being explored by ESA's Rosetta mission. The intensities of the CO Cameron band, atomic oxygen, and atomic carbon emission lines as a function of projected distance are calculated for different CO and CO{sub 2} volume mixing ratios relative to water. Contributions of different excitation processes controlling these emissions are quantified. We assess how CO{sub 2} and/or CO volume mixing ratios with respect to H{sub 2}O can be derived based on the observed intensities of the CO Cameron band, atomic oxygen, and atomic carbon emission lines. The results presented in this work serve as baseline calculations to understand the behavior of low out-gassing cometary coma and compare them with the higher gas production rate cases (e.g., comet Halley). Quantitative analysis of different excitation processes governing the spectroscopic emissions is essential to study the chemistry of inner coma and to derive neutral gas composition.

  4. Photopolymer material sensitized by xanthene dyes for holographic recording using forbidden singlet-triplet electronic transitions

    NASA Astrophysics Data System (ADS)

    Shelkovnikov, Vladimir; Vasiljev, Evgeny; Russkih, Vladimlen; Berezhnaya, Viktoria

    2016-07-01

    A new holographic photopolymer material is developed. The photopolymer material is sensitized by dyes of xanthene and thioxanthene series which contain iodine and bromine heavy atoms. Holographic recording was carried out during excitation of forbidden singlet-triplet electron transitions of dyes. Thioerythrosin triethylammonium was identified as the most effective sensitizer among a number of tested dyes. The spectral absorption area of the singlet-triplet electronic transition of the dye is conveyed in the red spectral range from 600 to 700 nm. The sensitivity of the photopolymer material to radiation with 633 nm wavelength is 180 mJ cm-2. Optimization of concentration of the main components of the photopolymer compositions was carried out in order to achieve maximum efficiency of holographic recording.

  5. The Absolute Mass of Neutrino and the First Unique Forbidden β-DECAY of 187Re

    NASA Astrophysics Data System (ADS)

    Dvornický, Rastislav; Šimkovic, Fedor; Muto, Kazuo

    2011-10-01

    The planned rhenium β-decay experiment MARE might probe the absolute mass scale of neutrinos with the same sensitivity as the tritium β-decay experiment KATRIN, which will start data taking in 2011 and will proceed for five years. We present the energy distribution of emitted electrons for the first unique forbidden β-decay of 187Re. It is found that the p-wave emission of electron dominates over the s-wave. By assuming mixing of three neutrinos the Kurie function for the rhenium β-decay is derived. It is shown that the Kurie plot near the endpoint is within a good accuracy linear in the limit of massless neutrinos like the Kurie plot of the superallowed βof 3H.

  6. Absolute mass of neutrinos and the first unique forbidden β decay of Re187

    NASA Astrophysics Data System (ADS)

    Dvornický, Rastislav; Muto, Kazuo; Šimkovic, Fedor; Faessler, Amand

    2011-04-01

    The planned rhenium β-decay experiment, called the “Microcalorimeter Arrays for a Rhenium Experiment” (MARE), might probe the absolute mass scale of neutrinos with the same sensitivity as the Karlsruhe tritium neutrino mass (KATRIN) experiment, which will take commissioning data in 2011 and will proceed for 5 years. We present the energy distribution of emitted electrons for the first unique forbidden β decay of Re187. It is found that the p-wave emission of electron dominates over the s wave. By assuming mixing of three neutrinos, the Kurie function for the rhenium β decay is derived. It is shown that the Kurie plot near the end point is within a good accuracy linear in the limit of massless neutrinos like the Kurie plot of the superallowed β decay of H3.

  7. Absolute mass of neutrinos and the first unique forbidden {beta} decay of {sup 187}Re

    SciTech Connect

    Dvornicky, Rastislav; Simkovic, Fedor; Muto, Kazuo; Faessler, Amand

    2011-04-15

    The planned rhenium {beta}-decay experiment, called the ''Microcalorimeter Arrays for a Rhenium Experiment'' (MARE), might probe the absolute mass scale of neutrinos with the same sensitivity as the Karlsruhe tritium neutrino mass (KATRIN) experiment, which will take commissioning data in 2011 and will proceed for 5 years. We present the energy distribution of emitted electrons for the first unique forbidden {beta} decay of {sup 187}Re. It is found that the p-wave emission of electron dominates over the s wave. By assuming mixing of three neutrinos, the Kurie function for the rhenium {beta} decay is derived. It is shown that the Kurie plot near the end point is within a good accuracy linear in the limit of massless neutrinos like the Kurie plot of the superallowed {beta} decay of {sup 3}H.

  8. Semiclassical nonadiabatic surface-hopping wave function expansion at low energies: hops in the forbidden region.

    PubMed

    Herman, Michael F

    2008-12-18

    The accuracy of a semiclassical surface-hopping expansion of the time-independent wave function for problems in which the nonadiabatic coupling is peaked in the classically forbidden regions is studied numerically for a one-dimensional curve-crossing problem. This surface-hopping expansion has recently been shown to satisfy the Schrodinger equation to all orders in h and all orders in the nonadiabatic coupling. It has also been found to provide very accurate transition probabilities for problems in which the crossing points of the diabatic energy surfaces are classically allowed. In the numerical study reported here, transition probabilities are evaluated for energies well below the crossing point energy. It is found that the expansion provides accurate results for transition probabilities as small as 10(-11).

  9. The plasmon-forbidden deep sub-wavelength transmission with the TE polarization.

    PubMed

    Chen, Minfeng; Chang, Hung-chun

    2009-08-03

    As is well-known, the sub-wavelength transmissions and field enhancement are related to the surface plasmon excitation. Here we demonstrate that in two-layer metallic gratings the deep sub-wavelength transmissions is supported with the TE polarization where the surface plasmon mode is forbidden. The new mechanism to the sub-wavelength transmission is discovered to be completely different from the findings in the literatures. we propose a simple resonance condition to classify the resonance types which are responsible for those sub-wavelength transmissions and confirm with numerical simulations. To give a complete explanation of underlying physics, we inspect the near-field phenomenon within the grating slits.

  10. The forbidden quest and the analytic ideal: the superego and insight.

    PubMed

    Blum, H P

    1981-10-01

    As is evident in the history of civilization, in myths and dreams, and in Freud's self-analysis, insight has been both prohibited and heroically sought. Psychoanalytic insight into unconscious processes and contents involves a gradual transformation of inner interdictions and ideals through the tolerance of previously forbidden curiosity and knowledge. The analytic process depends upon relaxation of censorship and analysis of the motives and modes of self-criticism and self-punishment. While the superego may also uphold truth, the ideal of insight into psychic reality is relatively rare. The formation and consolidation of an analytic ideal of insight is an outgrowth of and contribution to analysis and analytic education. Analytic education should result in freedom from inner constraints on insight, in independent thought and judgement, and in a continuing "after-education."

  11. Precise determination of the 113Cd fourth-forbidden non-unique β -decay Q value

    NASA Astrophysics Data System (ADS)

    Gamage, N. D.; Bollen, G.; Eibach, M.; Gulyuz, K.; Izzo, C.; Kandegedara, R. M. E. B.; Redshaw, M.; Ringle, R.; Sandler, R.; Valverde, A. A.

    2016-08-01

    Using Penning trap mass spectrometry, we have performed a precise determination of the Q value for the highly forbidden β decay of 113Cd. An independent measurement of the Q value fixes the end-point energy in a fit to the 113Cdβ -decay spectrum. This provides a strong test of systematics for detectors that have observed this decay, such as those developed for β β -decay searches in cadmium and other isotopes. It will also aid in the theoretical description of the β -decay spectrum. The result, Qβ=323.89 (27 ) keV , agrees at the 1.3 σ level with the value obtained from the 2012 Atomic Mass Evaluation [Chin. Phys. C 36, 1603 (2012), 10.1088/1674-1137/36/12/003], but is a factor of almost four more precise. We also report improved values for the atomic masses of 113Cd,113In, and 112Cd.

  12. Quantifying stochasticity in the dynamics of delay-coupled semiconductor lasers via forbidden patterns.

    PubMed

    Tiana-Alsina, Jordi; Buldú, Javier M; Torrent, M C; García-Ojalvo, Jordi

    2010-01-28

    We quantify the level of stochasticity in the dynamics of two mutually coupled semiconductor lasers. Specifically, we concentrate on a regime in which the lasers synchronize their dynamics with a non-zero lag time, and the leader and laggard roles alternate irregularly between the lasers. We analyse this switching dynamics in terms of the number of forbidden patterns of the alternate time series. The results reveal that the system operates in a stochastic regime, with the level of stochasticity decreasing as the lasers are pumped further away from their lasing threshold. This behaviour is similar to that exhibited by a single semiconductor laser subject to external optical feedback, as its dynamics shifts from the regime of low-frequency fluctuations to coherence collapse. This journal is © 2010 The Royal Society

  13. Magnetically Induced Optical Transparency on a Forbidden Transition in Strontium for Cavity-Enhanced Spectroscopy

    NASA Astrophysics Data System (ADS)

    Winchester, Matthew N.; Norcia, Matthew A.; Cline, Julia R. K.; Thompson, James K.

    2017-06-01

    In this Letter we realize a narrow spectroscopic feature using a technique that we refer to as magnetically induced optical transparency. A cold ensemble of 88Sr atoms interacts with a single mode of a high-finesse optical cavity via the 7.5 kHz linewidth, spin forbidden 1S0 to 3P1 transition. By applying a magnetic field that shifts two excited state Zeeman levels, we open a transmission window through the cavity where the collective vacuum Rabi splitting due to a single level would create destructive interference for probe transmission. The spectroscopic feature approaches the atomic transition linewidth, which is much narrower than the cavity linewidth, and is highly immune to the reference cavity length fluctuations that limit current state-of-the-art laser frequency stability.

  14. Laser spectroscopy on forbidden transitions in trapped highly charged Ar(13+) ions.

    PubMed

    Mäckel, V; Klawitter, R; Brenner, G; Crespo López-Urrutia, J R; Ullrich, J

    2011-09-30

    We demonstrate resonant fluorescence laser spectroscopy in highly charged ions (HCI) stored in an electron beam ion trap by investigating the dipole-forbidden 1s(2)2s(2)2p (2)P(3/2)-(2)P(1/2) transition in boronlike Ar(13+) ions. Forced evaporative cooling yielded a high resolving power, resulting in an accurate wavelength determination to λ=441.255 68(26)  nm. By applying stronger cooling and two-photon excitation, new optical frequency standards based upon ultrastable transitions in such HCI could be realized in the future, e.g., for the search of time variations of the fine-structure constant.

  15. Full Polarization Analysis of Resonant Superlattice and Forbidden x-ray Reflections in Magnetite

    SciTech Connect

    Wilkins, S.B.; Bland, S.R.; Detlefs, B.; Beale, T.A.W.; Mazzoli, C.; Joly, Y.; Hatton, P.D.; Lorenzo, J.E.; Brabers, V.A.M.

    2009-12-02

    Despite being one of the oldest known magnetic materials, and the classic mixed valence compound, thought to be charge ordered, the structure of magnetite below the Verwey transition is complex and the presence and role of charge order is still being debated. Here, we present resonant x-ray diffraction data at the iron K-edge on forbidden (0, 0, 2n+1){sub C} and superlattice (0, 0, 2n+1/2)C reflections. Full linear polarization analysis of the incident and scattered light was conducted in order to explore the origins of the reflections. Through simulation of the resonant spectra we have confirmed that a degree of charge ordering takes place, while the anisotropic tensor of susceptibility scattering is responsible for the superlattice reflections below the Verwey transition. We also report the surprising result of the conversion of a significant proportion of the scattered light from linear to nonlinear polarization.

  16. The Amigó paradigm of forbidden/missing patterns: a detailed analysis

    NASA Astrophysics Data System (ADS)

    Rosso, O. A.; Carpi, L. C.; Saco, P. M.; Ravetti, M. G.; Larrondo, H. A.; Plastino, A.

    2012-12-01

    We deal here with the issue of determinism versus randomness in time series (TS), with the goal of identifying their relative importance in a given TS. To this end we extend (i) the use of ordinal patterns based probability distribution functions associated to a TS [C. Bandt and B. Pompe, Phys. Rev. Lett. 88, 174102 (2002)] and (ii) the so-called Amigó paradigm of forbidden/missing patterns [J.M. Amigó et al., Europhys. Lett. 79, 50001 (2007)], to analyze deterministic finite TS contaminated with strong additive noises of different correlation-degree. Useful information on the deterministic component of the original time series is obtained with the help of the so-called causal entropy-complexity plane [O.A. Rosso et al., Phys. Rev. Lett. 99, 154102 (2007)].

  17. Multiplex PCR assay for the detection of five meat species forbidden in Islamic foods.

    PubMed

    Ali, Md Eaqub; Razzak, Md Abdur; Hamid, Sharifah Bee Abd; Rahman, Md Mahfujur; Amin, Md Al; Rashid, Nur Raifana Abd; Asing

    2015-06-15

    Food falsification has direct impact on public health, religious faith, fair-trades and wildlife. For the first time, here we described a multiplex polymerase chain reaction assay for the accurate identification of five meat species forbidden in Islamic foods in a single assay platform. Five pairs of species-specific primers were designed targeting mitochondrial ND5, ATPase 6, and cytochrome b genes to amplify 172, 163, 141, 129 and 108 bp DNA fragments from cat, dog, pig, monkey and rat meats, respectively. All PCR products were identified in gel-images and electrochromatograms obtained from Experion Bioanalyzer. Species-specificity checking against 15 important meat and fish and 5 plant species detected no cross-species amplification. Screening of target species in model and commercial meatballs reflected its application to detect target species in process foods. The assay was tested to detect 0.01-0.02 ng DNA under raw states and 1% suspected meats in meatball formulation.

  18. Some features of the radial-velocity variations of lines of different intensity in the spectrum of HD 93521. Variability of the stellar wind

    NASA Astrophysics Data System (ADS)

    Rzaev, A. Kh.

    2007-12-01

    CCD spectra taken with the PFES echelle spectrograph of the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences are used to perform a detailed study of the variability of the profiles of Hell, H β, and H α lines in the spectrum of HD 93521. The pattern and nature of the variability of the Hell lines are similar to those of weak HeI lines and are due to nonradial pulsations. The period and amplitude of the radial-velocity variations are the same for the blue and red halves of the absorption profile but their phases are opposite. The behavior of the variations of H β and H α hydrogen lines relative to their mean profiles is the same as that of strong HeI line and is due to nonradial pulsations. The period and phase of the radial-velocity oscillations are the same for the blue and red halves of the absorption profile but their amplitude are different. The behavior of the radial-velocity variations of the absorption and emission components of the H α line indicates that the latter also are caused by nonradial pulsations. All this is indicative of the complex structure of the stellar wind in the region of its origin. The behavior of variability and wind kinematics differ in different directions and for different regions of the atmosphere and/or envelope.

  19. Allowed and unique first-forbidden stellar electron emission rates of neutron-rich copper isotopes

    NASA Astrophysics Data System (ADS)

    Majid, Muhammad; Nabi, Jameel-Un; Daraz, Gul

    2017-06-01

    The allowed charge-changing transitions are the most common weak interaction processes of spin-isospin form that play a crucial role in several nuclear/astrophysical processes. The first-forbidden (FF) transition becomes important, in the circumstances where allowed Gamow-Teller (GT) transitions are unfavored, specifically for neutron-rich nuclei due to phase space considerations. In this paper deformed proton-neutron quasi-particle random phase approximation (pn-QRPA) model is applied, for the first time, for the estimation of allowed GT and unique first-forbidden (U1F) transitions (|Δ J| = 2) of neutron rich copper isotopes in mass range 72 ≤ A ≤ 82 under stellar conditions. We compared our computed terrestrial β-decay half-life values with previous calculations and experimental results. It was concluded that the pn-QRPA calculation is in good accordance with measured data. Our study suggests that the addition of rank (0 and 1) operators in FF transitions can further improve the comparison which remain unattended at this stage. The deformed pn-QRPA model was employed for the estimation of GT and U1F stellar electron emission (β--decay) rates over wide range of stellar temperature (0.01 GK-30 GK) and density (10-10^{11} g/cm3) domains for astrophysical applications. Our study shows that, in high density and low temperature regions, the contribution of U1F rates to total electron emission rates of neutron-rich copper nuclei is negligible.

  20. Resonance Scattering of Fe XVII X-ray and EUV Lines

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Saba, J. L. R.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Over the years a number of calculations have been carried out to derive intensities of various X-ray and EUV lines in Fe XVII to compare with observed spectra. The predicted intensities have not agreed with solar observations, particularly for the line at 1.5.02 Angstroms; resonance scattering has been suggested as the source for much of the disagreement. The atomic data calculated earlier used seven configurations having n=3 orbitals and the scattering calculations were carried out only for incident energies above the threshold of the highest fine-structure level. These calculations have now been extended to thirteen configurations having n=4 orbitals and the scattering calculations are carried out below as well as above the threshold of the highest fine structure level. These improved calculations of Fe XVII change the intensity ratios compared to those obtained earlier, bringing the optically thin F(15.02)/F(16.78) ratio and several other ratios closer to the observed values. However, some disagreement with the solar observations still persists, even thought the agreement of the presently calculated optically thin F(15.02)/F(15.26) ratio with the experimental results of Brown et al. (1998) and Laming et al. (2000) has improved. Some of the remaining discrepancy is still thought to be the effect of opacity, which is consistent with expected physical conditions for solar sources. EUV intensity ratios are also calculated and compared with observations. Level populations and intensity ratios are calculated, as a function of column density of Fe XVII, in the slab and cylindrical geometries. As found previously, the predicted intensities for the resonance lines at 15.02 and 15.26 Angstroms exhibit initial increases in flux relative to the forbidden line at 17.10 Angstroms and the resonance line at 16.78 Angstroms as optical thickness increases. The same behavior is predicted for the lines at 12.262 and 12.122 Angstroms. Predicted intensities for some of the allowed

  1. Parity- and spin-forbidden optical transitions of Cr{sup +3} in GdAlO{sub 3}

    SciTech Connect

    Basso, H.C.

    1997-10-01

    In this paper, the electric-dipole transition induced by exchange is used to explain the strong dependence of spin- and parity-forbidden transitions of Cr{sup +3} on the sublattice magnetization of an antiferromagnet host. {copyright} {ital 1997} {ital The American Physical Society}

  2. Forbidden Transitions in the Microwave Rotational Spectrum of the Tt Conformer of the N-Propanol Molecule

    NASA Astrophysics Data System (ADS)

    Kazimova, S. B.

    2016-01-01

    A search for forbidden transitions was made in the microwave rotational spectrum of the Tt conformer of the propanol molecule (n-CH3CH2CH2OH) in the region of 37.0-78.0 GHz. The n-CH3CH2CH2OH molecule has a plane of symmetry containing μb and μa components of the dipole moment (μc = 0). On account of centrifugal distortion an induced component of the dipole moment μa, perpendicular to the symmetry plane of the molecule and leading to the appearance of previously forbidden rotational transitions, appears in such molecules. Forbidden "centrifugal transitions" of this type were found in the microwave rotational spectrum of the Tt conformer of the n-CH3CH2CH2OH molecule. The spectrum was analyzed by means of the Watson A-reduction rotational Hamiltonian. Sixty four forbidden μc transitions with rotational quantum numbers of up to J = 37 inclusive were identified.

  3. Devaluation of Forbidden Toys Among Lower Socioeconomic Children as a Function of Severity and Specificity of Threat.

    ERIC Educational Resources Information Center

    Dembroski, Theodore M.; And Others

    A prediction derived from cognitive dissonance theory is that children devalue an attractive but forbidden toy when mild rather than severe threat deters them from playing with it. One study found the opposite effect for lower socioeconomic class children, i.e., a harsh verbal threat produced more devaluation than a mild threat. Since the latter…

  4. Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. IV - Intensity variations of the optical emission lines of NGC 5548

    NASA Technical Reports Server (NTRS)

    Dietrich, M.; Kollatschny, W.; Peterson, B. M.; Bechtold, J.; Bertram, R.; Bochkarev, N. G.; Boroson, T. A.; Carone, T. E.; Elvis, M.; Filippenko, A. V.

    1993-01-01

    Measurements of optical emission-line flux variations based on spectra of the Seyfert galaxy NGC 5548 obtained between December 1988 and October 1989 are reported. All of the measured optical emission lines, H-alpha, H-beta, H-gamma, He I 5876, and He II 4686, exhibit the same qualitative behavior as the UV and optical continua, but with short time delays, or lags, which are different for the various lines. Cross-correlation analysis is applied to measure the lags between the various lines and the continuum. Similar lags are found with respect to the UV continuum for H-alpha and H-beta, 17 and 19 d, respectively. The lag for H-gamma is shorter (13 d), only somewhat larger than the lag measured for Ly-alpha (about 10 d). The helium lines respond to continuum variations more rapidly than the hydrogen lines, with lags of about 7 d for He II 4686 and 11 d for He I 5876.

  5. Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. IV - Intensity variations of the optical emission lines of NGC 5548

    NASA Technical Reports Server (NTRS)

    Dietrich, M.; Kollatschny, W.; Peterson, B. M.; Bechtold, J.; Bertram, R.; Bochkarev, N. G.; Boroson, T. A.; Carone, T. E.; Elvis, M.; Filippenko, A. V.

    1993-01-01

    Measurements of optical emission-line flux variations based on spectra of the Seyfert galaxy NGC 5548 obtained between December 1988 and October 1989 are reported. All of the measured optical emission lines, H-alpha, H-beta, H-gamma, He I 5876, and He II 4686, exhibit the same qualitative behavior as the UV and optical continua, but with short time delays, or lags, which are different for the various lines. Cross-correlation analysis is applied to measure the lags between the various lines and the continuum. Similar lags are found with respect to the UV continuum for H-alpha and H-beta, 17 and 19 d, respectively. The lag for H-gamma is shorter (13 d), only somewhat larger than the lag measured for Ly-alpha (about 10 d). The helium lines respond to continuum variations more rapidly than the hydrogen lines, with lags of about 7 d for He II 4686 and 11 d for He I 5876.

  6. Oxygen isotope fractionation during spin-forbidden photolysis of CO2: Relevance to the atmosphere of Mars

    NASA Astrophysics Data System (ADS)

    Lyons, J. R.; Stark, G.; Pack, A.; de Oliveira, N.; Nahon, L.

    2015-12-01

    The oxygen isotope composition of the Martian atmosphere is of interest for comparison with recent MSL SAM results, and to understand the origin of oxygen isotope anomalies (i.e., mass-independent fractionation or MIF) in secondary minerals in SNC meteorites. Our focus here is on spin-forbidden photolysis of CO2, CO2 + hv (>167 nm) → CO(X1S) + O(3P). The spin-forbidden photolysis of CO2 is unusual in the Martian atmosphere because of its high reaction rate from the upper atmosphere (80 km) all the way to the ground. This range of altitudes spans 4 orders of magnitude in atmospheric pressure, and occurs because of the gradual decrease in the CO2 cross sections from 167 to ~200 nm. Previous laboratory photolysis experiments on CO2 in the spin-allowed and spin-forbidden regions have yielded a remarkably large MIF signature (17O excess ~ 100 permil) in O2 product for photolysis at 185 nm. Recent theoretical cross sections for CO2 isotopologues argue for a much smaller MIF signature from spin-forbidden photolysis. Here, we report the results of photolysis experiments on CO2 at the Soleil synchrotron DESIRS beamline. High purity, natural isotope abundance CO2 was placed in a 20 cm photocell with MgF2 windows. Experiments were performed at 3 wavelengths (7% FWHM): 160 nm (spin-allowed), and at 175 nm and 185 nm (spin-forbidden). After VUV exposure, aliquots of the photolyzed CO2 were sent to the Department of Isotope Geology at the University of Goettingen for O isotope analysis. The isotope results show that the spin-allowed photolysis yields normal, mass-dependent fractionation in agreement with earlier work. Photolysis at 175 nm, which is mostly spin-forbidden, yields a small positive (or zero) MIF signature. Photolysis at 185 nm, which is entirely spin-forbidden, yields O2 with a negative MIF signature (D17O ~ -8 to -10 permil). The results at 185 nm disagree in magnitude and sign with the very large positive MIF signature previously reported, and provides support

  7. Homogeneous and inhomogeneous broadenings and the Voigt line shapes in the phase-resolved and intensity sum-frequency generation vibrational spectroscopy

    SciTech Connect

    Chen, Shunli; Fu, Li; Gan, Wei; Wang, Hongfei

    2016-01-21

    In this report we show that the ability to measure the sub-1 cm-1 resolution phase-resolved and intensity high-resolution broadband sum frequency generation vibrational spectra (HR-BB-SFG-VS) of the –CN stretch vibration of the Langmuir-Blodgett (LB) monolayer of the 4-n-octyl-4’-cyanobiphenyl (8CB) on the z-cut α-quartz surface allows for the first time the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral lineshapes in detail. The difference of the full width at half maxima (FWHM) of the imaginary and intensity SFG-VS spectra of the same vibrational mode is the signature of the Voigt lineshape and it measures the relative contribution to the overall lineshape from the homogeneous and inhomogeneous broadenings in SFG vibrational spectra. From the phase-resolved and intensity spectra, we found that the FWHM of the 2238.00 ±0.02 cm-1 peak in the phase-resolved imaginary and intensity spectra is 19.2 ± 0.2 cm-1 and 21.6 ± 0.4 cm-1, respectively, for the –CN group of the 8CB LB monolayer on the z-cut α-quartz crystal surface. The FWHM width difference of 2.4 cm-1 agrees quantitatively with a Voigt lineshape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm-1 and a inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm-1. These results shed new lights on the understanding and interpretation of the lineshapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general.

  8. Composition determination of quaternary GaAsPN layers from single X-ray diffraction measurement of quasi-forbidden (002) reflection

    SciTech Connect

    Tilli, J.-M. Jussila, H.; Huhtio, T.; Sopanen, M.; Yu, K. M.

    2014-05-28

    GaAsPN layers with a thickness of 30 nm were grown on GaP substrates with metalorganic vapor phase epitaxy to study the feasibility of a single X-ray diffraction (XRD) measurement for full composition determination of quaternary layer material. The method is based on the peak intensity of a quasi-forbidden (002) reflection, which is shown to vary with changing arsenic content for GaAsPN. The method works for thin films with a wide range of arsenic contents and shows a clear variation in the reflection intensity as a function of changing layer composition. The obtained thicknesses and compositions of the grown layers are compared with accurate reference values obtained by Rutherford backscattering spectroscopy combined with nuclear reaction analysis measurements. Based on the comparison, the error in the XRD defined material composition becomes larger with increasing nitrogen content and layer thickness. This suggests that the dominating error source is the deteriorated crystal quality due to the nonsubstitutional incorporation of nitrogen into the crystal lattice and strain relaxation. The results reveal that the method overestimates the arsenic and nitrogen content within error margins of about 0.12 and about 0.025, respectively.

  9. Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. II - An intensive study of NGC 5548 at optical wavelengths

    NASA Technical Reports Server (NTRS)

    Peterson, B. M.; Balonek, T. J.; Barker, E. S.; Bechtold, J.; Bertram, R.

    1991-01-01

    A large, international program of ground-based optical spectroscopy and photometry of the variable Seyfert 1 galaxy NGC 5548 undertaken in support of an IUE monitoring campaign is described. This contribution presents the data base and describes the methods used to correct for systematic differences between spectra from different sources. Optical continuum and H-beta emission-line light curves are derived from the spectra. The behavior of the optical continuum is qualitatively the same as the behavior of the ultraviolet continuum. Cross-correlation of the ultraviolet and optical continuum measurements does not reveal any significant lag between them. The h-beta emission-line variations show the same basic pattern as seen in the continuum and ultraviolet emission lines, with H-beta lagging behind the continuum by about 20 days. This is significantly larger than the about 10 day lag deduced for Ly-alpha.

  10. Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. II. An intensive study of NGC 5548 at optical wavelengths

    SciTech Connect

    Peterson, B.M.; Balonek, T.J.; Barker, E.S.; Bechtold, J.; Bertram, R. Lick Observatory, Santa Cruz, CA Colgate Univ., Hamilton, NY Texas Univ., Austin Steward Observatory, Tucson, AZ )

    1991-02-01

    A large, international program of ground-based optical spectroscopy and photometry of the variable Seyfert 1 galaxy NGC 5548 undertaken in support of an IUE monitoring campaign is described. This contribution presents the data base and describes the methods used to correct for systematic differences between spectra from different sources. Optical continuum and H-beta emission-line light curves are derived from the spectra. The behavior of the optical continuum is qualitatively the same as the behavior of the ultraviolet continuum. Cross-correlation of the ultraviolet and optical continuum measurements does not reveal any significant lag between them. The h-beta emission-line variations show the same basic pattern as seen in the continuum and ultraviolet emission lines, with H-beta lagging behind the continuum by about 20 days. This is significantly larger than the about 10 day lag deduced for Ly-alpha. 15 refs.

  11. Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. II - An intensive study of NGC 5548 at optical wavelengths

    NASA Technical Reports Server (NTRS)

    Peterson, B. M.; Balonek, T. J.; Barker, E. S.; Bechtold, J.; Bertram, R.

    1991-01-01

    A large, international program of ground-based optical spectroscopy and photometry of the variable Seyfert 1 galaxy NGC 5548 undertaken in support of an IUE monitoring campaign is described. This contribution presents the data base and describes the methods used to correct for systematic differences between spectra from different sources. Optical continuum and H-beta emission-line light curves are derived from the spectra. The behavior of the optical continuum is qualitatively the same as the behavior of the ultraviolet continuum. Cross-correlation of the ultraviolet and optical continuum measurements does not reveal any significant lag between them. The h-beta emission-line variations show the same basic pattern as seen in the continuum and ultraviolet emission lines, with H-beta lagging behind the continuum by about 20 days. This is significantly larger than the about 10 day lag deduced for Ly-alpha.

  12. Intensity Frontier Instrumentation

    SciTech Connect

    Kettell S.; Rameika, R.; Tshirhart, B.

    2013-09-24

    The fundamental origin of flavor in the Standard Model (SM) remains a mystery. Despite the roughly eighty years since Rabi asked “Who ordered that?” upon learning of the discovery of the muon, we have not understood the reason that there are three generations or, more recently, why the quark and neutrino mixing matrices and masses are so different. The solution to the flavor problem would give profound insights into physics beyond the Standard Model (BSM) and tell us about the couplings and the mass scale at which the next level of insight can be found. The SM fails to explain all observed phenomena: new interactions and yet unseen particles must exist. They may manifest themselves by causing SM reactions to differ from often very precise predictions. The Intensity Frontier (1) explores these fundamental questions by searching for new physics in extremely rare processes or those forbidden in the SM. This often requires massive and/or extremely finely tuned detectors.

  13. The ionization structure of the Orion Nebula - Infrared line observations and models

    NASA Technical Reports Server (NTRS)

    Simpson, J. P.; Rubin, R. H.; Erickson, E. F.; Haas, M. R.

    1986-01-01

    Observations of the forbidden O III 52 and 88 microns lines and the forbidden N III 57 microns line have been made at six positions and the forbidden Ne III 36 microns line at four positions in the Orion Nebula to probe its ionization structure. The wavelength of the forbidden Ne III line was measured to be 36.009-36.017 microns. Electron densities and abundance ratios of N(++)/O(++) have been calculated and compared to other radio and optical observations. Detailed one-component and two-component (bar plus halo) spherical models were calculated for exciting stars with effective temperatures of 37,000-40,000 K and log g = 4.0 and 4.5. Both the new IR observations and the visible line measurements of oxygen and nitrogen require Teff of no more than 37,000 K. However, the doubly ionized neon requires a model with Teff of at least 39,000 K, which is more consistent with that inferred from the radio flux or spectral type. These differences in Teff are not due to effects of dust on the stellar radiation field but are probably due to inaccuracies in the assumed stellar spectrum. Neon and nitrogen are approximately solar, but oxygen is half-solar in abundance. From the IR O(++) lines, it is concluded that the ionization bar results from an increase in column depth rather than from a local density enhancement.

  14. Ionization structure of the Orion Nebula - infrared line observations and models

    SciTech Connect

    Simpson, J.P.; Rubin, R.H.; Erickson, E.F.; Haas, M.R.

    1986-12-01

    Observations of the forbidden O III 52 and 88 microns lines and the forbidden N III 57 microns line have been made at six positions and the forbidden Ne III 36 microns line at four positions in the Orion Nebula to probe its ionization structure. The wavelength of the forbidden Ne III line was measured to be 36.009-36.017 microns. Electron densities and abundance ratios of N(++)/O(++) have been calculated and compared to other radio and optical observations. Detailed one-component and two-component (bar plus halo) spherical models were calculated for exciting stars with effective temperatures of 37,000-40,000 K and log g = 4.0 and 4.5. Both the new IR observations and the visible line measurements of oxygen and nitrogen require Teff of no more than 37,000 K. However, the doubly ionized neon requires a model with Teff of at least 39,000 K, which is more consistent with that inferred from the radio flux or spectral type. These differences in Teff are not due to effects of dust on the stellar radiation field but are probably due to inaccuracies in the assumed stellar spectrum. Neon and nitrogen are approximately solar, but oxygen is half-solar in abundance. From the IR O(++) lines, it is concluded that the ionization bar results from an increase in column depth rather than from a local density enhancement. 54 references.

  15. The ionization structure of the Orion Nebula - Infrared line observations and models

    NASA Technical Reports Server (NTRS)

    Simpson, J. P.; Rubin, R. H.; Erickson, E. F.; Haas, M. R.

    1986-01-01

    Observations of the forbidden O III 52 and 88 microns lines and the forbidden N III 57 microns line have been made at six positions and the forbidden Ne III 36 microns line at four positions in the Orion Nebula to probe its ionization structure. The wavelength of the forbidden Ne III line was measured to be 36.009-36.017 microns. Electron densities and abundance ratios of N(++)/O(++) have been calculated and compared to other radio and optical observations. Detailed one-component and two-component (bar plus halo) spherical models were calculated for exciting stars with effective temperatures of 37,000-40,000 K and log g = 4.0 and 4.5. Both the new IR observations and the visible line measurements of oxygen and nitrogen require Teff of no more than 37,000 K. However, the doubly ionized neon requires a model with Teff of at least 39,000 K, which is more consistent with that inferred from the radio flux or spectral type. These differences in Teff are not due to effects of dust on the stellar radiation field but are probably due to inaccuracies in the assumed stellar spectrum. Neon and nitrogen are approximately solar, but oxygen is half-solar in abundance. From the IR O(++) lines, it is concluded that the ionization bar results from an increase in column depth rather than from a local density enhancement.

  16. Atomic data from the Iron project. XIII. Electron excitation rates and emissivity ratios for forbidden transitions in NI II and Fe II.

    NASA Astrophysics Data System (ADS)

    Bautista, M. A.; Pradhan, A. K.

    1996-02-01

    Electron impact excitation rates and emissivity line ratios are reported for Optical and IR transitions in Ni II and Fe II arising from low-lying even parity levels. A total of 7 LS terms were included for Ni II, which result in 17 fine structure levels and 136 transitions. Coupling effects and resonance structures considered in the present calculations result in significant differences with the earlier distorted wave calculations by Nussbaumer & Storey (1982), although a reasonable agreement is found for the line diagnostics of some strong transitions in Ni II. Whereas an extensive set of collisional data has been presented earlier by Zhang & Pradhan for Fe II in the Iron Project series, in this paper we report collision strengths for some transitions missing from their dataset using an improved eigenfunction expansion for Fe II which includes the lowest 18 LS terms giving 52 fine structure levels and 1326 transitions. The present dataset provides a useful check on several forbidden transitions in Fe II and essentially confirms the diagnostics derived from the earlier work. The present calculations were carried out on the massively parallel processor Cray T3D with a parallelized version of the Iron Project R-matrix codes; to our knowledge these are the first such calculations.

  17. Experimental and theoretical studies of the npσ1Σu+ and npπ1 Πu+ (n ⩾ 4,N‧ = 1 -6) states of D2: Energies, natural widths, absorption line intensities, and dynamics

    NASA Astrophysics Data System (ADS)

    Glass-Maujean, M.; Jungen, Ch.; Vasserot, A. M.; Schmoranzer, H.; Knie, A.; Kübler, S.; Ehresmann, A.; Ubachs, W.

    2017-08-01

    Over a thousand spectral lines in the photoexcitation spectrum of molecular deuterium (D2) to np1 Σu+ and 1Πu+ Rydberg levels (n ⩾ 4) were measured for rotational levels N‧ = 1 -6 in the 117 000-137 000 cm-1 spectral range by two different types of experiments at two synchrotron radiation sources: a vacuum ultraviolet (VUV) Fourier-transform (FT) spectrometer at SOLEIL, Paris and a 10 m-normal-incidence monochromator (NIM) at BESSY II, Berlin. The experimental energies, the absorption cross sections, Einstein A-coefficients, and line widths are compared with ab initio multi-channel quantum defect (MQDT) calculations for these levels. More than 350 R(0) or P(2) lines were assigned, some 280 R(1) or P(3) lines, some 270 R(2) or P(4) lines, over 100 R(3) or P(5) lines, over 90 R(4) lines, and 24 R(5) lines to extract information on the N‧ = 1 -6 excited levels. Transition energies were determined up to excitation energies of 137 000 cm-1 above the ground state, thereby extending earlier work by various authors and considerably improving the spectral accuracy (< 0.1 cm-1), leading to several reassignments. The absorption and the dissociation, ionization and fluorescence excitation cross sections from the NIM experiment are measured on absolute scale and are used to calibrate intensities in the VUV-FT spectra. The overall agreement between experiment and first principles calculations, without adjustable parameters, is excellent in view of the multi-state interferences treated within the MQDT-framework: For the low N‧ values the averaged deviations between those observed in the FT-SOLEIL spectra and those calculated with MQDT are ∼ 0.1 cm-1 with a spread of ∼ 0.5 cm-1. The line intensities in terms of Einstein coefficients are well represented in the MQDT-framework, as are the level widths representing the lifetimes associated with the sum of the three decay channels. These line intensities follow, in general, the 1 /n3 scaling behavior as characteristic in

  18. VizieR Online Data Catalog: Collision Strengths for [Co III] Forbidden Lines - SS5 (Storey+, 2016)

    NASA Astrophysics Data System (ADS)

    Storey, P. J.; Sochi, T.

    2016-04-01

    The data set consists of 105 files which are labeled as 'OMEGAmn_CoIII.dat' where m=1,2,...,14 and n=2,3,...,15 with m

  19. VizieR Online Data Catalog: Collision Strengths for [Co II] Forbidden Lines - SS4 (Storey+, 2016)

    NASA Astrophysics Data System (ADS)

    Storey, P. J.; Zeippen, C. J.; Sochi, T.

    2016-02-01

    The data set consists of 105 files which are labeled as 'OMEGAmn_CoII.dat' where m=1,2,...,14 and n=2,3,...,15 with m

  20. VizieR Online Data Catalog: 3D model for fitting forbidden OI 6300 line (Socas-Navarro, 2015)

    NASA Astrophysics Data System (ADS)

    Socas-Navarro, H.

    2015-04-01

    modelin.mod and modelout.mod contain three-dimensional cubes each column represents the physical stratification of each pixel, with the in and the out suffix referring to the two atmospheric components coexisting with the filling factor. The code manual has details on the file format and the variables stored. (3 data files).

  1. Determining tunable diode laser spectrometer performance through measurement of N(2)0 line intensities and widths at 7.8 microm.

    PubMed

    Chen, D W; Niple, E R; Poultney, S K

    1982-08-15

    The N(2)O R(8) doublet of the 11(1)0-01(1)0 band at 7.8 microm was measured by a tunable diode laser spectrometer designed and assembled at Perkin-Elmer. The spectra were digitized and least-squares fitted to Voigt line profiles to yield N(2)O line parameters and a quantitative measure of instrument performance. Scans at various pressures produced consistent spectral line values: S(0) = (0.1746 +/- 0.0043)cm(-2)/atm at 300 K, alpha(L)(N(2)O - N(2)O) = (0.1066 +/- 0.0041)cm(-1)/atm,alpha(D) = (1.194 +/- 0.018) x 10(-3) cm(-1), andalpha(L)(N(2)O - N(2)) = (0.0870 +/- 0.0015)cm(-1)atm. A spectrum with several levels of synthetic noise added was used to verify the fitting algorithm's stability. The spectrometer was shown to possess an excellent SNR (e.g., 900:1) and wave number precision (

  2. Gufa, a unique cultural ritual--a tale of forbidden sun and a girl

    NASA Astrophysics Data System (ADS)

    Shrestha, Pritisha

    2015-08-01

    Gufa, one of the traditional rituals has been performed in Nepal since time immemorial by an especial indigenous Newar people. Gufa, in its literal translation means cave. Just like in the cave where darkness seeps deep within its wall as the sun’s ray cannot penetrate, in the ritual of Gufa, a young girl who just had her first period is hidden in a dark room for twelve consecutive days. The girl, by strict custom and ritual performance stays in the room, protected from the sun’s light. From her female elders, she also receives informal education on family and societal values and norms.Sun, the reason behind our existence, is forbidden for the girl to observe. This very aspect of purely shunning away from the sun has become the crucial aspect for delving into the explanations offered by cultural astronomy. The present paper would argue that astronomy and astronomy education should not only focus on looking into the future, but also should go back to the ancient civilization to comprehend ritual performance our forefathers had learned from gazing the sky.After twelve days, the girl is carefully brought out to an open space where she sees the forbidden sun and symbolically marries the star via ritual. The logic behind the union after a pure restriction is to protect her sensitive young body and to ward off any harm to her reproductive parts from the sun’s harsh rays.From astronomical point, this logic behind protecting the girl from the effects of then deemed harmful rays should be studied. In ancient times, who with which instruments could have possibly fathom the life-giving sun could harness harmful solar rays. Although it looks like a primitive custom of hiding the girl immediately during her first period, there are logical social, cultural and scientific reasons for doing it even today in modern, urban and among the educated Newar households of Nepal and abroad.The paper would expound the importance of traditional ritual performance and its nexus with

  3. A Comparison of the Red and Green Coronal Line Intensities at the 29 March 2006 and the 1 August 2008 Total Solar Eclipses: Considerations of the Temperature of the Solar Corona

    NASA Astrophysics Data System (ADS)

    Voulgaris, A.; Athanasiadis, T.; Seiradakis, J. H.; Pasachoff, J. M.

    2010-06-01

    During the total solar eclipse at Akademgorodok, Siberia, Russia, on 1 August 2008, we imaged the flash spectrum with a slitless spectrograph. We have spectroscopically determined the duration of totality, the epoch of the second and third contacts and the duration of the flash spectrum. Here we compare the 2008 flash spectra with those that we similarly obtained from the total solar eclipse of 29 March 2006, at Kastellorizo, Greece. Any changes of the intensity of the coronal emission lines, in particularly those of Fe x and Fe xiv, could give us valuable information about the temperature of the corona. The results show that the ionization state of the corona, as manifested especially by the Fe xiv emission line, was much weaker during the 2008 eclipse, indicating that following the long, inactive period during the solar minimum, there was a drop in the overall temperature of the solar corona.

  4. Observation of intense Stokes and anti-Stokes lines in CH4 pumped by 355 nm of a Nd:YAG laser

    NASA Technical Reports Server (NTRS)

    Sentrayan, K.; Major, L.; Michael, A.; Kushawaha, V.

    1992-01-01

    The stimulated Raman scattering (SRS) and four-wave mixing (FWM) processes are studied in detail in CH4 gas pumped by the third-harmonic of Nd:YAG laser at 355 nm. The conversion efficiency and average output energy are measured for the various Stokes and anti-Stokes lines at different experimental conditions. The threshold input energy at various CH4 pressures is calculated for the unguided and capillary waveguide Raman cells. The calculated values for the capillary case are compared with the measured values at different CH4 pressures and the two results are in good agreement.

  5. Forbidden beta decays of {sup 96}Zr and {sup 115}In: Implications for neutrino physics

    SciTech Connect

    Mustonen, M. T.; Suhonen, J.

    2009-11-09

    We summarize our theoretical results for two nuclides of interest for the double-beta decay and neutrino mass studies: {sup 96}Zr and {sup 115}In.The double-beta decay of {sup 96}Zr competes with three highly-forbidden beta-decay channels. Our microscopic nuclear-structure calculations imply that the half-life of the first-order beta-decay channels is an order of magnitude longer than that of the double-beta decay.In the work of C. T. Cattadori et al. it was discovered that {sup 115}In can beta decay to the first excited state of {sup 115}Sn. It was also suggested that this decay might provide a supplementary way of accessing the neutrino mass. The recent half-life measurement carried out in the underground laboratory HADES confirms the existence and refines the half-life of this decay channel. At the same time the precision mass measurements made at the University of Jyvaeskylae yield the record-setting ultra-low Q value of 0.35(17) keV. Our theoretical analysis of this decay suggests that atomic effects could play an important role in relating the measured half-life to the measured Q value.

  6. Spin‐Forbidden Branching in the Mechanism of the Intrinsic Haber–Weiss Reaction

    PubMed Central

    Leitão, Ezequiel F. V.; Ventura, Elizete; de Souza, Miguel A. F.

    2017-01-01

    Abstract The mechanism of the O2 ⋅− and H2O2 reaction (Haber–Weiss) under solvent‐free conditions has been characterized at the DFT and CCSD(T) level of theory to account for the ease of this reaction in the gas phase and the formation of two different set of products (Blanksby et al., Angew. Chem. Int. Ed. 2007, 46, 4948). The reaction is shown to proceed through an electron‐transfer process from the superoxide anion to hydrogen peroxide, along two pathways. While the O3 ⋅− + H2O products are formed from a spin‐allowed reaction (on the doublet surface), the preferred products, O⋅−(H2O)+3O2, are formed through a spin‐forbidden reaction as a result of a favorable crossing point between the doublet and quartet surface. Plausible reasons for the preference toward the latter set are given in terms of the characteristics of the minimum energy crossing point (MECP) and the stability of an intermediate formed (after the MECP) in the quartet surface. These unique results show that these two pathways are associated with a bifurcation, yielding spin‐dependent products. PMID:28638768

  7. Asymptotic Structure in the Classically Forbidden Region of the Hooke's Atoms

    NASA Astrophysics Data System (ADS)

    Wang, Xue-Mei

    2013-05-01

    The two-electron Hooke's atom — a quantum mechanical system with two electrons bound in a harmonic potential — is well known for its exact analytical properties at certain oscillator strengths. The Hooke's atoms with more than two electrons offer more scope for valuable practical applications. In this work, we study the asymptotic structure of these Hooke's atoms in the classically forbidden region. The leading-order term of the long-range expression for the KS exchange-correlation potential vxc(r) is shown to be -1/r. The second and third higher order terms are also exactly obtained. Various components of vxc(r) are also studied. It is shown that the leading term of O(1/r) in vxc(r) is due to the pure Pauli correlation, while the leading contribution of the Coulomb correlation is of O(1/r3). Neither of them makes contribution to the term of O(1/r2), which is shown to be solely due to the kinetic correlation effect. Results for the two-electron Hooke's atom were obtained before in the literature. Our results reduce to those of the two-electron Hooke's atom as a special case.

  8. Vervet monkeys solve a multiplayer "forbidden circle game" by queuing to learn restraint.

    PubMed

    Fruteau, Cécile; van Damme, Eric; Noë, Ronald

    2013-04-22

    In social dilemmas, the ability of individuals to coordinate their actions is crucial to reach group optima. Unless exacted by power or force, coordination in humans relies on a common understanding of the problem, which is greatly facilitated by communication. The lack of means of consultation about the nature of the problem and how to solve it may explain why multiagent coordination in nonhuman vertebrates has commonly been observed only when multiple individuals react instantaneously to a single stimulus, either natural or experimentally simulated, for example a predator, a prey, or a neighboring group. Here we report how vervet monkeys solved an experimentally induced coordination problem. In each of three groups, we trained a low-ranking female, the "provider," to open a container holding a large amount of food, which the providers only opened when all individuals dominant to them ("dominants") stayed outside an imaginary "forbidden circle" around it. Without any human guidance, the dominants learned restraint one by one, in hierarchical order from high to low. Once all dominants showed restraint immediately at the start of the trial, the providers opened the container almost instantly, saving all individuals opportunity costs due to lost foraging time. Solving this game required trial-and-error learning based on individual feedback from the provider to each dominant, and all dominants being patient enough to wait outside the circle while others learned restraint. Communication, social learning, and policing by high-ranking animals played no perceptible role. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Forbidden phonon: Dynamical signature of bond symmetry breaking in the iron chalcogenides

    DOE PAGES

    Fobes, David M.; Zaliznyak, Igor A.; Tranquada, John M.; ...

    2016-09-01

    Investigation of the inelastic neutron scattering spectra in Fe1+yTe1₋xSex near a signature wave vector Q=(1,0,0) for the bond-order wave (BOW) formation of parent compound Fe1+yTe reveals an acoustic-phonon-like dispersion present in all structural phases. While a structural Bragg peak accompanies the mode in the low-temperature phase of Fe1+yTe, it is absent in the high-temperature tetragonal phase, where Bragg scattering at this Q is forbidden by symmetry. Notably, this mode is also observed in superconducting FeTe0.55Se0.45, where structural and magnetic transitions are suppressed, and no BOW has been observed. Lastly, the presence of this “forbidden” phonon indicates that the lattice symmetrymore » is dynamically or locally broken by magneto-orbital BOW fluctuations, which are strongly coupled to lattice in these materials.« less

  10. Enabling forbidden processes: quantum and solvation enhancement of nitrate anion UV absorption.

    PubMed

    Svoboda, Ondřej; Kubelová, Lucie; Slavíček, Petr

    2013-12-05

    We present simulated electronic absorption spectra of isolated and solvated nitrate anion in the UV region, focusing primarily on the absorption into the first absorption band around 300 nm. This weak absorption band in this spectral region is responsible for the generation of NOx in the polar areas or OH(•) radicals in the hydrosphere. The 300 nm absorption band is symmetrically strongly forbidden and coupling of at least two vibrational modes is needed to allow the transition in the isolated nitrate anion. Further symmetry breaking is provided by solvation. In this study we model the absorption spectra of nitrate-water clusters using the combined reflection principle path integral molecular dynamics (RP-PIMD) method. Condensed phase UV spectra are modeled within a cluster-continuum model. The calculated spectra are compared with experimental bulk phase measurements and reasonable agreement is found. We also provide a benchmarking of the DFT functionals to be used for a description of the electronically excited states of solvated nitrate anion.

  11. Second unique forbidden {beta} decay of {sup 115}In and neutrino mass

    SciTech Connect

    Dvornicky, R.; Simkovic, F.

    2011-12-16

    The measurement of the electron spectrum in {beta} decays close to the end point provides a robust direct determination of the values of neutrino masses. The most sensitive experiments use tritium and rhenium {beta} decays because these transitions have low Q value. Recent measurement with Penning traps established that the {beta} decay of {sup 115}In(9/2{sup +}) to the first excited state of {sup 115}Sn(3/2{sup +}) is a transition with the smallest Q value among {beta} decays. The decay is associated with a change of spin and parity {Delta}J{sup {pi}} = 3{sup +} ({Delta}L = 2, {Delta}S = 1) of nucleus, i.e., classified as unique second forbidden {beta} decay. Our investigation shows that in this transition electrons are predominantly emitted in d{sub 5/2} partial waves. In addition, it is found that the Kurie function associated with this transition near the end point within a good accuracy reflects a behavior the Kurie function of superallowed {beta} transitions.

  12. The Life of Pi Star: Exploring the Exciting and Forbidden Worlds of the Benzophenone Photophore.

    PubMed

    Dormán, György; Nakamura, Hiroyuki; Pulsipher, Abigail; Prestwich, Glenn D

    2016-12-28

    The widespread applications of benzophenone (BP) photochemistry in biological chemistry, bioorganic chemistry, and material science have been prominent in both academic and industrial research. BP photophores have unique photochemical properties: upon n-π* excitation at 365 nm, a biradicaloid triplet state is formed reversibly, which can abstract a hydrogen atom from accessible C-H bonds; the radicals subsequently recombine, creating a stable covalent C-C bond. This light-directed covalent attachment process is exploited in many different ways: (i) binding/contact site mapping of ligand (or protein)-protein interactions; (ii) identification of molecular targets and interactome mapping; (iii) proteome profiling; (iv) bioconjugation and site-directed modification of biopolymers; (v) surface grafting and immobilization. BP photochemistry also has many practical advantages, including low reactivity toward water, stability in ambient light, and the convenient excitation at 365 nm. In addition, several BP-containing building blocks and reagents are commercially available. In this review, we explore the "forbidden" (transitions) and excitation-activated world of photoinduced covalent attachment of BP photophores by touring a colorful palette of recent examples. In this exploration, we will see the pros and cons of using BP photophores, and we hope that both novice and expert photolabelers will enjoy and be inspired by the breadth and depth of possibilities.

  13. Forbidden phonon: Dynamical signature of bond symmetry breaking in the iron chalcogenides

    SciTech Connect

    Fobes, David M.; Zaliznyak, Igor A.; Tranquada, John M.; Xu, Zhijun; Gu, Genda; He, Xu-Gang; Ku, Wei; Zhao, Yang; Matsuda, Masaaki; Garlea, V. Ovidiu; Winn, Barry

    2016-09-01

    Investigation of the inelastic neutron scattering spectra in Fe1+yTe1₋xSex near a signature wave vector Q=(1,0,0) for the bond-order wave (BOW) formation of parent compound Fe1+yTe reveals an acoustic-phonon-like dispersion present in all structural phases. While a structural Bragg peak accompanies the mode in the low-temperature phase of Fe1+yTe, it is absent in the high-temperature tetragonal phase, where Bragg scattering at this Q is forbidden by symmetry. Notably, this mode is also observed in superconducting FeTe0.55Se0.45, where structural and magnetic transitions are suppressed, and no BOW has been observed. Lastly, the presence of this “forbidden” phonon indicates that the lattice symmetry is dynamically or locally broken by magneto-orbital BOW fluctuations, which are strongly coupled to lattice in these materials.

  14. Exploration of the forbidden regions of the Ramachandran plot (ϕ-ψ) with QTAIM.

    PubMed

    Momen, Roya; Azizi, Alireza; Wang, Lingling; Ping, Yang; Xu, Tianlv; Kirk, Steven R; Li, Wenxuan; Manzhos, Sergei; Jenkins, Samantha

    2017-09-25

    A new QTAIM interpretation of the Ramachandran plot is formulated from the most and least facile eigenvectors of the second-derivative matrix of the electron density with a set of 29 magainin-2 peptide conformers. The presence of QTAIM eigenvectors associated with the most and least preferred directions of electronic charge density explained the role of hydrogen bonding, HH contacts and the glycine amino acid monomer in peptide folding. The highest degree of occupation of the QTAIM interpreted Ramachandran plot was found for the glycine amino acid monomer compared with the remaining backbone peptide bonds. The mobility of the QTAIM eigenvectors of the glycine amino acid monomer was higher than for the other amino acids and was comparable to that of the hydrogen bonding, explaining the flexibility of the magainin-2 backbone. We experimented with a variety of hybrid QTAIM-Ramachandran plots to highlight and explain why the glycine amino acid monomer largely occupies the 'forbidden' region on the Ramachandran plot. In addition, the new hybrid QTAIM-Ramachandran plots contained recognizable regions that can be associated with concepts familiar from the conventional Ramachandran plot whilst retaining the character of the QTAIM most and least preferred regions.

  15. High-resolution laser spectroscopy of ultracold ytterbium atoms using spin-forbidden electric quadrupole transition

    NASA Astrophysics Data System (ADS)

    Uetake, S.; Yamaguchi, A.; Hashimoto, D.; Takahashi, Y.

    2008-11-01

    We have successfully observed high-resolution spectra of spin-forbidden electric quadrupole transition (1 S 0→3 D 2) in ytterbium (174Yb) atoms. The differential light shifts between the 1 S 0 and the 3 D 2 states in a far-off resonant trap at 532 nm are also measured. For the spectroscopy, we developed simple, narrow-linewidth, and long-term frequency stabilized violet diode laser systems. Long-term drifts of the excitation laser (404 nm) is suppressed by locking the laser to a length stabilized optical cavity. The optical path length of the cavity is stabilized to another diode laser whose frequency is locked to a strong 1 S 0→1 P 1 transition (399 nm) of Yb. Both lasers are standard extended-cavity diode lasers (ECDLs) in the Littrow configuration. Since the linewidth of a violet ECDL (˜10 MHz) is broader than a typical value of a red or near infra-red ECDL (<1 MHz), we employ optical feedback from a narrow-band Fabry-Perot cavity to reduce the linewidth. The linewidth is expected to be <20 kHz for 1 ms averaging time, and the long-term frequency stability is estimated to be ˜200 kHz/h.

  16. Spin-Forbidden Branching in the Mechanism of the Intrinsic Haber-Weiss Reaction.

    PubMed

    Leitão, Ezequiel F V; Ventura, Elizete; de Souza, Miguel A F; Riveros, José M; do Monte, Silmar A

    2017-06-01

    The mechanism of the O2(⋅-) and H2O2 reaction (Haber-Weiss) under solvent-free conditions has been characterized at the DFT and CCSD(T) level of theory to account for the ease of this reaction in the gas phase and the formation of two different set of products (Blanksby et al., Angew. Chem. Int. Ed. 2007, 46, 4948). The reaction is shown to proceed through an electron-transfer process from the superoxide anion to hydrogen peroxide, along two pathways. While the O3(⋅-) + H2O products are formed from a spin-allowed reaction (on the doublet surface), the preferred products, O(⋅-)(H2O)+(3)O2, are formed through a spin-forbidden reaction as a result of a favorable crossing point between the doublet and quartet surface. Plausible reasons for the preference toward the latter set are given in terms of the characteristics of the minimum energy crossing point (MECP) and the stability of an intermediate formed (after the MECP) in the quartet surface. These unique results show that these two pathways are associated with a bifurcation, yielding spin-dependent products.

  17. Theoretical investigation on spin-forbidden cooling transitions of gallium hydride.

    PubMed

    Zhang, Yun-Guang; Zhang, Hua; Song, Hai-Yang; Yu, You; Wan, Ming-Jie

    2017-09-20

    Herein, the spin-forbidden cooling of a gallium hydride molecule is investigated using ab initio quantum chemistry. The cooling transition and the corresponding potential energy curves including , a(3)Π0(-), a(3)Π0(+), a(3)Π1, a(3)Π2, A(1)Π1, , 1(3)Σ, , , and 2(3)Σ states are simulated based on the multi-reference configuration interaction approach plus Davidson corrections method. By solving the nuclear Schrödinger equation, we calculate the spectroscopic constants of these states, which are in good agreement with the available experimental values. Based on the transition data, there seems to be a theoretical puzzle: highly diagonally distributed Franck-Condon factor f00 for transitions , , and for the gallium hydride molecule but the intervening state A(1)Π1 for transition is prohibitive to laser cooling. In addition, the transition does not have a suitable rate of optical cycling owing to a large radiative lifetime for state. Our theoretical simulation indicates the solution to the puzzle: the transition has a high emission rate, and there is a suitable radiative lifetime for a(3)Π1 state, which can ensure rapid and efficient laser cooling of gallium hydride. The proposed laser drives transition by using three wavelengths (main pump laser λ00; two repumping lasers λ10 and λ21). These results demonstrate the possibility of laser-cooling the gallium hydride molecule, and a sub-microkelvin cool temperature can be reached for this molecule.

  18. A B cell explanation for autoimmune disease: the forbidden clone returns.

    PubMed

    McQueen, Fiona

    2012-04-01

    More than 60 years ago, Burnet first proposed the 'forbidden clone' hypothesis postulating that autoimmune disease arises as a result of persistence of self-reactive clones of lymphocytes that should have been deleted via immune tolerance. These autoreactive clones could effect immune-mediated end-organ damage via peripheral self-antigen recognition. Recent evidence that stretches across the boundaries of many medical specialties supports this proposal, implicating a B cell precursor as the culprit. The success of B cell depleting therapy in rheumatoid arthritis, anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitis, polymyositis, lupus and autoimmune diseases as diverse as multiple sclerosis and idiopathic thrombocytopenic purpura supports this proposal. Clonality of B cells and plasma cells has been described in a number of autoimmune disorders and the presence of autoantibodies, which may arise years before the onset of clinical disease, supports the notion of autoreactivity within the B cell lineage. T cell activation within the end-organ would be predicted by cognate B-T cell interactions and resultant tissue inflammation and destruction could produce diverse clinical manifestations dictated by the original specificity of the autoimmune B cell.

  19. Accessing Forbidden Glass Regimes through High-Pressure Sub-Tg Annealing

    PubMed Central

    Svenson, Mouritz N.; Mauro, John C.; Rzoska, Sylwester J.; Bockowski, Michal; Smedskjaer, Morten M.

    2017-01-01

    Density and hardness of glasses are known to increase upon both compression at the glass transition temperature (Tg) and ambient pressure sub-Tg annealing. However, a serial combination of the two methods does not result in higher density and hardness, since the effect of compression is countered by subsequent annealing and vice versa. In this study, we circumvent this by introducing a novel treatment protocol that enables the preparation of high-density, high-hardness bulk aluminosilicate glasses. This is done by first compressing a sodium-magnesium aluminosilicate glass at 1 GPa at Tg, followed by sub-Tg annealing in-situ at 1 GPa. Through density, hardness, and heat capacity measurements, we demonstrate that the effects of hot compression and sub-Tg annealing can be combined to access a “forbidden glass” regime that is inaccessible through thermal history or pressure history variation alone. We also study the relaxation behavior of the densified samples during subsequent ambient pressure sub-Tg annealing. Density and hardness are found to relax and approach their ambient condition values upon annealing, but the difference in relaxation time of density and hardness, which is usually observed for hot compressed glasses, vanishes for samples previously subjected to high-pressure sub-Tg annealing. This confirms the unique configurational state of these glasses. PMID:28418017

  20. Forbidden phonon: Dynamical signature of bond symmetry breaking in the iron chalcogenides

    SciTech Connect

    Fobes, David M.; Zaliznyak, Igor A.; Tranquada, John M.; Xu, Zhijun; Gu, Genda; He, Xu-Gang; Ku, Wei; Zhao, Yang; Matsuda, Masaaki; Garlea, V. Ovidiu; Winn, Barry

    2016-09-01

    Investigation of the inelastic neutron scattering spectra in Fe1+yTe1₋xSex near a signature wave vector Q=(1,0,0) for the bond-order wave (BOW) formation of parent compound Fe1+yTe reveals an acoustic-phonon-like dispersion present in all structural phases. While a structural Bragg peak accompanies the mode in the low-temperature phase of Fe1+yTe, it is absent in the high-temperature tetragonal phase, where Bragg scattering at this Q is forbidden by symmetry. Notably, this mode is also observed in superconducting FeTe0.55Se0.45, where structural and magnetic transitions are suppressed, and no BOW has been observed. Lastly, the presence of this “forbidden” phonon indicates that the lattice symmetry is dynamically or locally broken by magneto-orbital BOW fluctuations, which are strongly coupled to lattice in these materials.