Science.gov

Sample records for high-resolution infrared spectra

  1. High Resolution Infrared Spectra of Triacetylene

    NASA Astrophysics Data System (ADS)

    Doney, Kirstin D.; Zhao, Dongfeng; Linnartz, Harold

    2015-06-01

    Triacetylene, HC6H, is the longest poly-acetylene chain found in space, and is believed to be involved in the formation of longer chain molecules and polycyclic aromatic hydrocarbons (PAHs). However, abundances are expected to be low, and observational confirmation requires knowledge of the gas-phase spectra, which up to now has been incomplete with only the weak, low lying bending modes being known. We present new infrared (IR) spectra in the C-H stretch region obtained using ultra-sensitive and highly precise IR continuous wave cavity ring-down spectroscopy (cw-CRDS), combined with supersonic plasma expansions The talk reviews the accurate determination of the rotational constants of the asymmetric fundamental mode, νb{5}, including discussion on the perturber state, and associated hot bands. The determined molecular parameters are accurate enough to aid astronomical searches with such facilities as ALMA (Atacama Large Millimeter Array) or the upcoming JWST (James Webb Space Telecscope), which can now probe even trace molecules (abundances of ˜ 10-6 - 10-10 with respect to H2). D. Zhao, J. Guss, A. Walsh, H. Linnartz, Chem. Phys. Lett., 565, 132 (2013) K.D. Doney, D. Zhao, H. Linnartz, in preparation

  2. Atlas of high resolution infrared spectra of carbon dioxide

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Benner, D. C.; Devi, V. M.; Ferry, P. S.; Sutton, C. H.; Richardson, D. J.

    1984-01-01

    An atlas of long-path room-temperature absorption spectra of carbon dioxide is presented for the spectral intervals 1830-2100 cm, 2395-2680 cm, and 3140-3235 cm. The spectral data were recorded at high signal to noise with the 0.01 cm resolution Fourier transform interferometer. The spectra were obtained with pressures between 1 and 10 Torr of CO2 and with total paths between 24 and 384 meters. A compilation of the measured line positions and the assignments derived from the analysis are presented. Of the 3336 lines in the atlas, 94 percent were identified as CO2 lines or as residual lines H2O and CO. Calculated positions are presented for the carbon dioxide lines; a total of 52 bands of C-12O2-16, C-13O2-16, C-12O-16O-18, C-12O-16O-17, and C-13O-16O18 were identified. The weakest carbon dioxide lines marked in the atlas have intensities of approximately 0.5 x 10 to the negative 26th power cm/molecule at room temperature.

  3. Optimal Extraction of High-Resolution Spectra From the Infrared Spectrograph on Spitzer

    NASA Astrophysics Data System (ADS)

    Sloan, Gregory

    We propose to develop optimal extraction for the high-resolution modules on the Infrared Spectrograph (IRS) aboard the Spitzer Space Telescope, apply it to the full archive of IRS data, and post the results on a publicly available website. The currently used extraction algorithm sums everything in the slit, both source and backgrond emission. The new scheme will separate the source from its background, making it possible to analyze spectra taken in complex fields and generally improving the signal/noise quality of the data by a factor of nearly two. Most of the currently available high-resolution spectra require further reduction before they can be analyzed. Our improvements to the data will open the science contained in the thousands of high-resolution IRS observations to the full astronomy community. We will test our algorithm on high-resolution IRS spectra of young stellar objects in the Large Magellanic Cloud, which will ensure both an immediate science return, a polished extraction algorithm, and a reliable archive of optimally extracted spectra from all of the high-resolution IRS observations available to the astronomical community. The result will build on the momentum of CASSIS, the Cornell Atlas of of Spitzer/IRS Sources, which curently contains over 12,000 optimally extracted low-resolution spectra from the IRS. It will be a valuable addition to the legacy of the IRS and Spitzer.

  4. CRIRES-POP. A library of high resolution spectra in the near-infrared

    NASA Astrophysics Data System (ADS)

    Lebzelter, T.; Seifahrt, A.; Uttenthaler, S.; Ramsay, S.; Hartman, H.; Nieva, M.-F.; Przybilla, N.; Smette, A.; Wahlgren, G. M.; Wolff, B.; Hussain, G. A. J.; Käufl, H. U.; Seemann, U.

    2012-03-01

    Context. New instrumental capabilities and the wealth of astrophysical information extractable from the near-infrared wavelength region have led to a growing interest in the field of high resolution spectroscopy at 1-5 μm. Aims: We aim to provide a library of observed high-resolution and high signal-to-noise-ratio near-infrared spectra of stars of various types throughout the Hertzsprung-Russell diagram. This is needed for the exploration of spectral features in this wavelength range and for comparison of reference targets with observations and models. Methods: High quality spectra were obtained using the CRIRES near-infrared spectrograph at ESO's VLT covering the range from 0.97 μm to 5.3 μm at high spectral resolution. Accurate wavelength calibration and correction for telluric lines were performed by fitting synthetic transmission spectra for the Earth's atmosphere to each spectrum individually. Results: We describe the observational strategy and the current status and content of the library which includes 13 objects. The first examples of finally reduced spectra are presented. This publication will serve as a reference paper to introduce the library to the community and explore the extensive amount of material. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile (084.D-0912, 085.D-0161, 086.D-0066, and 087.D-0195).The spectra presented in Figs. 3 to 15 are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/539/A109

  5. Physical parameters of T dwarfs derived from high-resolution near-infrared spectra

    NASA Astrophysics Data System (ADS)

    Del Burgo, C.; Martín, E. L.; Zapatero Osorio, M. R.; Hauschildt, P. H.

    2009-07-01

    Aims: We determine the effective temperature, surface gravity and projected rotational velocity of nine T dwarfs from the comparison of high-resolution near-infrared spectra and synthetic models, and estimate the mass and age of the objects from state-of-the-art models. Methods: We use the AMES-COND cloudless solar metallicity models provided by the PHOENIX code to match the spectra of nine T-type field dwarfs observed with the near-infrared high-resolution spectrograph NIRSPEC using ten echelle orders to cover part of the J band from 1.147 to 1.347 μm with a resolving power R˜20 000. The projected rotational velocity, effective temperature and surface gravity of the objects are determined based on the minimum root mean square of the differences between the modelled and observed relative fluxes. Estimates of the mass and age of the objects are obtained from effective temperature-surface gravity diagrams, where our results are compared with existing solar metallicity models. Results: The modelled spectra reproduce quite well the observed features for most of the T dwarfs, with effective temperatures in the range of 922-1009 K, and surface gravities between 104.1 and 104.9 cm s-2. Our results support the assumption of a dust free atmosphere for T dwarfs later than T5, where dust grains form and then gravitationally sediment into the low atmosphere. The modelled spectra do not accurately mimic some individual very strong lines like the K i doublet at 1.2436 and 1.2525 μm. Our modelled spectra does not match well the observed spectra of the two T dwarfs with earlier spectral types, namely SDSSp J125453.90-012247.4 (T2) and 2MASS J05591914-1404488 (T4.5), which is likely due to the presence of condensate clouds that are not incorporated in the models used here. By comparing our results and their uncertainties to evolutionary models, we estimate masses in the interval ≈5-75~MJ for T dwarfs later than T5, which are in good agreement with those found in the literature

  6. High resolution infrared measurements

    NASA Technical Reports Server (NTRS)

    Kessler, B.; Cawley, Robert

    1990-01-01

    Sample ground based cloud radiance data from a high resolution infrared sensor are shown and the sensor characteristics are presented in detail. The purpose of the Infrared Analysis Measurement and Modeling Program (IRAMMP) is to establish a deterministic radiometric data base of cloud, sea, and littoral terrain clutter to be used to advance the design and development of Infrared Search and Track (IRST) systems as well as other infrared devices. The sensor is a dual band radiometric sensor and its description, together with that of the Data Acquisition System (DAS), are given. A schematic diagram of the sensor optics is shown.

  7. Estimation of Venus wind velocities from high-resolution infrared spectra. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Smith, M. A. H.

    1978-01-01

    Zonal velocity profiles in the Venus atmosphere above the clouds were estimated from measured asymmetries of HCl and HF infrared absorption lines in high-resolution Fourier interferometer spectra of the planet. These asymmetries are caused by both pressure-induced shifts in the positions of the hydrogen-halide lines perturbed by CO2 and Doppler shifts due to atmospheric motions. Particularly in the case of the HCl 2-0 band, the effects of the two types of line shifts can be easily isolated, making it possible to estimate a profile of average Venus equatorial zonal velocity as a function of pressure in the region roughly 60 to 70 km above the surface of the planet. The mean profiles obtained show strong vertical shear in the Venus zonal winds near the cloud-top level, and both the magnitude and direction of winds at all levels in this region appear to vary greatly with longitude relative to the sub-solar point.

  8. New spectral features of stratospheric trace gases identified from high-resolution infrared balloon-borne and laboratory spectra

    NASA Technical Reports Server (NTRS)

    Goldman, A.; Murcray, F. J.; Blatherwick, R. D.; Kosters, J. J.; Murcray, F. H.; Murcray, D. G.; Rinsland, C. P.

    1989-01-01

    A new Michelson-type interferometer system operating in the infrared at very high resolution has been used to record numerous balloon-borne solar absorption spectra of the stratosphere, ground-based solar absorption spectra, and laboratory spectra of molecules of atmospheric interest. In the present work results obtained for several important stratospheric trace gases, HNO3, CIONO2, HO2NO2, NO2, and COF2, in the 8- to 12-micron spectral region are reported. Many new features of these gases have been identified in the stratospheric spectra. Comparison of the new spectra with line-by-line simulations shows that previous spectral line parameters are often inadequate and that new analysis of high-resolution laboratory and atmospheric spectra and improved theoretical calculations will be required for many bands. Preliminary versions of several sets of improved line parameters under development are discussed.

  9. Collaborative Study of Analysis of High Resolution Infrared Atmospheric Spectra Between NASA Langley Research Center and the University of Denver

    NASA Technical Reports Server (NTRS)

    Goldman, Aaron

    1999-01-01

    The Langley-D.U. collaboration on the analysis of high resolution infrared atmospheric spectra covered a number of important studies of trace gases identification and quantification from field spectra, and spectral line parameters analysis. The collaborative work included: Quantification and monitoring of trace gases from ground-based spectra available from various locations and seasons and from balloon flights. Studies toward identification and quantification of isotopic species, mostly oxygen and Sulfur isotopes. Search for new species on the available spectra. Update of spectroscopic line parameters, by combining laboratory and atmospheric spectra with theoretical spectroscopy methods. Study of trends of atmosphere trace constituents. Algorithms developments, retrievals intercomparisons and automatization of the analysis of NDSC spectra, for both column amounts and vertical profiles.

  10. Analysis of High-Resolution Infrared and CARS Spectra of ³⁴S¹⁸O₃

    SciTech Connect

    Masiello, Tony; Vulpanovici, Nicolae; Barber, Jeffrey B.; Chrysostom, Engelene; Nibler, Joseph W.; Maki, Arthur; Blake, Thomas A.; Sams, Robert L.; Weber, Alfons

    2004-09-11

    As part of a series of investigations of isotopic forms of sulfur trioxide, high-resolution infrared and coherent anti-Stokes Raman spectroscopies were used to study the fundamental modes and several hot bands of 32S18O3. Hot bands originating from the v2 and v4 bending mode levels have been found to couple strongly to the IR-inactive v1 symmetric stretching mode through indirect Coriolis interactions and Fermi resonances. Coriolis coupling effects are particularly noticeable in 32S18O3 due to the close proximity of the v2 and v4 fundamental vibrations, whose deperturbed wavenumber values are 486.488 13(4) and 504.284 77(4) cm-1. The uncertainties in the last digits are shown in parentheses and are two standard deviations. From the infrared transitions, accurate rovibrational constants are deduced for all of the mixed states, leading to deperturbed values for v1, and of 1004.68(2), 0.000 713(2), and 0.000 348(2) cm-1, respectively. The Be value is found to be 0.310 820(2) cm-1, yielding an equilibrium bond length re of 141.7333(4) pm that is, within experimental error, identical to the value of 141.7339(3) pm reported previously for 34S18O3. With this work, precise and accurate spectroscopic constants have now been determined in a systematic and consistent manner for all the fundamental vibrational modes of the sulfur trioxide D3h isotopomeric forms 32S16O3, 34S16O3, 32S18O3, and 34S18O3.

  11. Retrieval of Precise Radial Velocities from High Resolution Near-Infrared Spectra of M Dwarfs

    NASA Astrophysics Data System (ADS)

    Gao, Peter; Plavchan, Peter; Gagne, Jonathan; Furlan, Elise; Bottom, Michael; Anglada-Escudé, Guillem; White, Russel J.; Davison, Cassy; Mills, Sean; Beichman, Charles A.; Brinkworth, Carolyn; Johnson, John; Ciardi, David R.; Wallace, J. Kent; Mennesson, Bertrand; von Braun, Kaspar; Vasisht, Gautam; Prato, Lisa A.; Kane, Stephen R.; Tanner, Angelle M.; Walp, Bernie; Crawford, Sam; Lin, Sean

    2015-01-01

    We present a data analysis pipeline focused on obtaining precision radial velocities (RV) of M Dwarfs from spectra taken between 2.309 and 2.316 microns by the CSHELL spectrograph (R~46,000) at NASA's Infrared Telescope Facility with the aid of a methane isotopologue gas cell (see poster by Plavchan et al. at this meeting). The pipeline compares the observed spectra with a forward model defined by parameters that are optimized using a simplex amoeba algorithm. The stellar template is optimized simultaneously with the fit parameters in an iterative process. The pipeline accounts for temporal variations in the spectral wavelength solution, line spread function, and interference fringes due to instrumental effects. We apply our pipeline to the M Dwarfs GJ 15 A and GJ 876 and the M Giant SV Peg. For GJ 15 A, we are able to obtain 30 m/s RV precision. For the planet host GJ 876, the two most massive planets are easily retrievable from our RV curve. For SV Peg, the single night RV precision can be as low as 15 m/s, with < 5 m/s obtainable through data stacking.

  12. High-Resolution Infrared Spectra of Bicyclo[1.1.1]pentane

    SciTech Connect

    Martin, Matthew A.; Perry, Adam J.; Masiello, Tony; Schwartz, Keith D.; Nibler, Joseph W.; Weber, Alfons; Maki, Arthur; Blake, Thomas A.

    2010-07-01

    Infrared spectra of bicyclo[1.1.1]pentane (C5H8) have been recorded at a resolution (0.0015 cm-1) sufficient to resolve for the first time individual rovibrational lines. This initial report presents the ground state constants for this molecule determined from the detailed analysis of three of the ten infrared-allowed bands, v14(e′) at 540 cm-1, v17(a2″) at 1220 cm-1, v18(a2″) at 832 cm-1, and a partial analysis of the v11(e′) band at 1237 cm-1. The upper states of transitions involving the lowest frequency mode, v14(e′), show no evidence of rovibrational perturbations but those for the v17 and v18 (a2″) modes give clear indication of Coriolis coupling to nearby e′ levels. Accordingly, ground state constants were determined by use of the combination-difference method for all three bands. The assigned frequencies provided over 3300 consistent ground state difference values, yielding the following constants for the ground state (in units of cm-1): B0 = 0.2399412(2), DJ = 6.024(6) x 10-8, DJK = -1.930(21) x 10-8. For the unperturbed v14(e′) fundamental, more than 3500 transitions were analyzed and the band origin was found to be at 540.34225(2) cm-1. The numbers in parentheses are the uncertainties (two standard deviations) in the values of the constants. The results are compared with those obtained previously for [1.1.1]propellane and with those computed at the ab initio anharmonic level using the B3LYP density functional method with a cc-pVTZ basis set.

  13. High-Resolution Infrared Spectra of Spiropentane, C5H8

    SciTech Connect

    Price, Joseph E.; Coulterpark, K. A.; Masiello, Tony; Nibler, Joseph W.; Weber, Alfons; Maki, Arthur G.; Blake, Thomas A.

    2011-09-01

    Infrared spectra of spiropentane (C{sub 5}H{sub 8}) have been recorded at a resolution (0.002 cm{sup -1}) sufficient to resolve for the first time individual rovibrational lines. This initial report presents the ground state constants for this molecule determined from the detailed analysis of the {nu}16 (b2) parallel band at 993 cm{sup -1}. In addition, the determination included more than 2000 ground state combination-differences deduced from partial analyses of four other infrared-allowed bands, the {nu}24(e) perpendicular band at 780 cm{sup -1} and three (b2) parallel bands at 1540 cm{sup -1} ({nu}14), 1568 cm{sup -1} ({nu}5+{nu}16), and 2098 cm{sup -1} ({nu}5+{nu}14). In each of the latter four cases, the spectra show complications; in the case of {nu}24, these complications are due to rotational l-type doublings, and in the case of the parallel bands, the spectral complexities are due to Fermi resonance and Coriolis interactions of the upper states with nearby levels. The unraveling of these is underway but the assignment of many of these transitions permit the confident use of the ground state differences in determining the following constants for the ground state (in units of cm{sup -1}): B0 = 0.1394736(2), DJ = 2.458(1) x 10{sup -8}, DJK = 8.28(3) x 10{sup -8}. For the unperturbed {nu}16 fundamental, more than 3000 transitions were fit and the band origin was found to be at 992.53793(2) cm{sup -1}. The numbers in parentheses are the uncertainties (two standard deviations) in the value of the last digit of the constants. Surprisingly, the very accurate B0 value measured here is lower than the value (0.1418 cm{sup -1}) calculated from an electron diffraction structure, instead of being higher, as expected. Where possible, the rovibrational results are compared with those computed at the anharmonic level using the B3LYP density functional method with a cc-pVTZ basis set. These too suggest that the electron diffraction results are in question.

  14. High resolution infrared absorption spectra of various trace gases present in the upper atmosphere of the Earth

    NASA Technical Reports Server (NTRS)

    Hunt, Robert H.

    1988-01-01

    The objective of NASA Grant NsG 7473 was to obtain and analyze high resolution infrared absorption spectra of various trace gases present in the Earth's upper atmosphere. The goal of the spectral analysis was to obtain values of absorption line strengths, widths and frequencies of sufficient accuracy for use in upper atmosphere trace gas monitoring. During the early phase of the grant, high resolution spectra were obtained from two instruments. One was the 0.02/cm resolution vacuum grating spectrometer at the Florida State University and the other was the 0.01/cm resolution Fourier transform spectrometer at the McMath solar telescope at the Kitt Peak Observatory. Using these instruments, a considerable amount of spectra of methane and hydrogen peroxide were obtained and analyzed. During the latter years of the project, data taking was halted while efforts were devoted to building a new 0.0025/cm resolution vacuum Fourier transform spectrometer. Progress during this phase of the grant then became greatly slowed due to a lack of suitable graduate students in the program. However, the instrument was completed and brought to the point of producing interferograms.

  15. Analysis of High-Resolution Infrared and CARS Spectra of ³⁴S¹⁸O₃

    SciTech Connect

    Masiello, Tony; Barber, Jeffrey B.; Chrysostom, Engelene; Nibler, Joseph W.; Maki, Arthur; Weber, Alfons; Blake, Thomas A.; Sams, Robert L.

    2004-01-01

    Three fundamental modes and several hot bands of 34S18O3 have been investigated using both infrared spectroscopy and coherent anti-Stokes Raman scattering spectroscopy (CARS). Coriolis coupling effects are particularly noticeable in 34S18O3 due to the close proximity of the v2 and v4 fundamental vibrations, whose wavenumber values are 477.508 64(5) and 502.055 65(4) cm-1. The uncertainties in the last digits are shown in parentheses and are two standard deviations. Hot band transitions from v2, v4 levels give access to infrared inactive v2, v4 combination/overtone levels which interact strongly with levels of the Raman-active v1 symmetric stretching mode due to indirect Coriolis couplings, l-resonances, and Fermi resonances. The result is a complex v1 CARS Q- branch spectrum that is the most perturbed of the four SO3 isotopomers we have studied. The relative importance of these interaction terms on the v1 CARS spectrum is examined in some detail and accurate rovibrational constants are determined for all of the mixed states, leading to deperturbed values of 1004.662(24), 0.000 350 3(9), and 0.000 706 6(12) cm-1 for v1, α1B, and α1C, respectively. The B e value is found to be 0.310 817(12) cm-1, which gives an equilibrium bond length re of 141.7339(3) pm, in excellent agreement with values of 141.7340(1) and 141.7347(7) pm reported earlier for 32S16O3 and 34S16O3.

  16. High resolution visible to short-wave near-infrared CCD spectra of Mars during 1990

    NASA Technical Reports Server (NTRS)

    Bell, James F., III; Bornhoeft, Karl; Lucey, Paul G.

    1994-01-01

    The 0.4 to 1.0 micron spectrum of Mars is dominated by a steep red, relatively featureless spectral slope. Earlier lower spectral observations interpreted the red color and the lack of absorption features in the spectra as evidence of poorly crystalline ferric oxide minerals. More recent higher spectral resolution observations and reinterpretations of older data sets have revealed measureable spectral structure, however. For example, absorption features near 0.65 and 0.86 micron were detected and spatially mapped in data obtained during the 1988 opposition. These absorptions were interpreted as evidence for crystalline hematite on Mars, occuring as an accessory phase in abundances of 3 to 6 percent in the soil. We are attempting to verify the existence of these subtle crystalline Fe(3+) absorption features and to map their spatial distribution in regions of the planet not imaged in 1988. During the 1990 opposition, we obtained imaging spectroscopic data of Mars from the University of Hawaii 2.24 m telescope at Mauna Kea Observatory. The data were obtained with the Wide Field Grism Spectrograph (WFGS), which uses an 800 x 800 CCD and a transmission grating ruled on a prism. We used a grating blazed at 4800 A in first order to obtain data from 0.50 to 0.94 micron at a spectral resolution of R = 200 to 350. The moon/Mars slit design used had projected dimensions of 0.29 x 153 inches, allowing for high spectral resolution and adequate cross-slit spatial sampling of the Martian disk.

  17. High Resolution Infrared Spectra of Jet-Cooled Formamide and Formamide Dimer in the C=O Stretch Region

    NASA Astrophysics Data System (ADS)

    Sunahori, Fumie X.; Xu, Yunjie

    2012-06-01

    Formamide (FA) is the simplest molecule with a peptide bond. It has attracted considerable theoretical and spectroscopic attention as a model peptide. The structure of the FA monomer in the ground state was determined to be planar by rotational spectral analyses of several isotopic species. Its high resolution FIR spectrum and IR spectrum in the symmetric N-H stretching region were reported previously. Both matrix isolation and jet-cooled FTIR studies of FA dimer reported spectral evidence for the cyclic C2h symmetric FA dimer bonded by two NH---O bonds, which was predicted to be the most stable structure by ab initio calculations. No high-resolution spectrum of FA dimer, however, has been recorded so far. Our aim in the present study is to study high-resolution IR absorption spectra of both FA and its dimer in the C=O stretching region in order to gain information about the peptide-peptide interactions. IR spectrum of the FA monomer was measured using a rapid scan infrared laser spectrometer equipped with an astigmatic multipass cell. While the monomer band centers at 1754 cm-1, the lines most likely belonging to FA dimer were observed around 1740 cm-1. The spectral assignment of the C=O stretching band of the monomer was made by the means of ground state combination differences. Further data collection and spectral analysis of FA dimer are currently underway. The results will be updated at the conference. E. Hirota, R. Sugisaki, C. J. Nielsen, G. O. Sørensen, J. Mol. Spectrosc. 49, 251, 1974. C. L. Brummel, M. Shen, K. B. Hewett, L. A. Philips, J. Opt. Soc. Am. B, 11, 176, 1994 D. McNaughton, C. J. Evans, S. Lane, C. J. Nielsen, J. Mol. Spectrosc., 193, 104, 1999. A. Mardyukov, E. Sanchez-Garcia, P. Rodziewicz, N. L. Doltsinis, W. Sander, J. Phys. Chem. A., 111, 10552, 2007. M. Albrecht, C. A. Rice, M. A. Suhm, J. Phys. Chem. A., 112, 7530, 2008.

  18. Analysis of Atmospheric Trace Constituents from High Resolution Infrared Balloon-Borne and Ground-Based Solar Absorption Spectra

    NASA Technical Reports Server (NTRS)

    Goldman, A.; Murcray, F. J.; Rinsland, C. P.; Blatherwick, R. D.; Murcray, F. H.; Murcray, D. G.

    1991-01-01

    Recent results and ongoing studies of high resolution solar absorption spectra will be presented. The analysis of these spectra is aimed at the identification and quantification of trace constituents important in atmospheric chemistry of the stratosphere and upper troposphere. Analysis of balloon-borne and ground-based spectra obtained at 0.0025/ cm covering the 700-2200/ cm interval will be presented. Results from ground-based 0.02/ cm solar spectra, from several locations such as Denver, South Pole, M. Loa, and New Zealand will also be shown. The 0.0025/ cm spectra show many new spectroscopic features. The analysis of these spectra, along with corresponding laboratory spectra, improves the spectral line parameters, and thus the accuracy of trace constituents quantification. The combination of the recent balloon flights, with earlier flights data since 1978 at 0.02/ cm resolution, provides trends analysis of several stratospheric trace species. Results for COF2, F22, SF6, and other species will be presented. Analysis of several ground-based solar spectra provides trends for HCl, HF and other species. The retrieval methods used for total column density and altitude distribution for both ground-based and balloon-borne spectra will be presented. These are extended for the analysis of the ground-based spectra to be obtained by the high resolution interferometers of the Network for Detection of Stratospheric Change (NDSC). Progress or the University of Denver studies for the NDSC will be presented. This will include intercomparison of solar spectra and trace gases retrievals obtained from simultaneous scans by the high resolution (0.0025/ cm) interferometers of BRUKER and BOMEM.

  19. Quantification of HCl from high-resolution, ground-based, infrared solar spectra in the 3000 per cm region

    NASA Technical Reports Server (NTRS)

    Goldman, A.; Murcray, F. J.; Blatherwick, R. D.; Murcray, D. G.

    1986-01-01

    Recent ground-based infrared solar spectra at 0.02 per cm resolution in the 3000 per cm region have been analyzed for the atmospheric content of HCl. Nonlinear spectral least-squares fitting applied to spectra obtained at several zenith angles shows little sensitivity of the results to tropospheric HCl but provides an accurate measurement of the total column amount.

  20. Collaborative Study for Analysis of High Resolution Infrared Atmospheric Spectra Between NASA Langley Research Center and the University of Denver

    NASA Technical Reports Server (NTRS)

    Goldman, A.

    2002-01-01

    The Langley-D.U. collaboration on the analysis of high resolultion infrared atmospheric spectra covered a number of important studies of trace gases identification and quantification from field spectra, and spectral line parameters analysis. The collaborative work included: 1) Quantification and monitoring of trace gases from ground-based spectra available from various locations and seasons and from balloon flights; 2) Identification and preliminary quantification of several isotopic species, including oxygen and Sulfur isotopes; 3) Search for new species on the available spectra, including the use of selective coadding of ground-based spectra for high signal to noise; 4) Update of spectroscopic line parameters, by combining laboratory and atmospheric spectra with theoretical spectroscopy methods; 5) Study of trends and correlations of atmosphere trace constituents; and 6) Algorithms developments, retrievals intercomparisons and automatization of the analysis of NDSC spectra, for both column amounts and vertical profiles.

  1. High resolution Fourier transform infrared spectra and analysis of the ν14, ν15 and ν16 bands of azetidine

    NASA Astrophysics Data System (ADS)

    Zaporozan, Taras; Chen, Ziqiu; van Wijngaarden, Jennifer

    2010-12-01

    Rotationally resolved vibrational spectra of the three lowest frequency bands of the four-membered heterocycle azetidine (c-C 3H 6NH) have been collected with a resolution of 0.00096 cm -1 using the far infrared beamline at the Canadian Light Source synchrotron. The modes observed correspond principally to motions best described as: β-CH 2 rock ( ν14) at 736.701310(7) cm -1, ring deformation ( ν15) at 648.116041(8) cm -1, and the ring puckering mode ( ν16) at 207.727053(9) cm -1. A global fit of 14 276 rovibrational transitions from the three bands provided an accurate set of ground state spectroscopic constants as well as excited state parameters for each of the three vibrational modes. The ground state structure was determined to be that of the puckered conformer having the NH bond in an equatorial arrangement.

  2. High Resolution Infrared Spectra of Ar-Water and Ne-Water at 6 μm

    NASA Astrophysics Data System (ADS)

    Liu, X.; Xu, Y.

    2012-06-01

    Ar- and Ne-water are highly floppy van der Waals complexes where the water subunit experiences nearly free internal rotation. Their ro-vibrational energy levels are characterized by the internal rotor states of the water subunit within the complex and a pseudo-diatomic rotational energy Hamiltonian. Large amplitude motions of the complexes lead to strong perturbations, such as Coriolis coupling and angular-radial coupling among the internal rotor states and the van der Waals bending and stretching states. Mid-infrared spectra of Ar- and Ne-water were measured with a direct absorption spectrometer with an external cavity quantum cascade laser at 6 μm and a 366-pass astigmatic absorption cell. footnote{X. Liu, Y. Xu, Z. S., W. S. Tam, I. Leonov, {Appl. Phys. B}, \\underline{{102}}, 629, 2011} The scan-to-scan frequency instability of the laser was addressed with a ``on-the-fly'' calibration procedure. The infrared spectrum of Ar-water has been studied by Weida and Nesbitt, in which the Σ 110 and π 110 states have been identified. At least three new overlapping bands at 1630 cm-1 have been observed and two of them have been tentatively assigned to the n=1, Σ 101 gets π 110 and Σ 110 gets Σ 101 bands. The n=1, π 101 gets Σ 101 band that was missing in the previous study was found at 1639 cm-1. Four new bands in the 1645-1665 cm-1 region have been observed and assigned to the π 212 gets π 101, Σ 212 gets Σ 101, π 212 gets Σ 101, and n=1, Σ 111 gets Σ 000. A global fit of the microwave, far-infrared, near-infrared and mid-infrared data was performed with Pickett's SPFIT program to determine the spectroscopic constants of these levels. Infrared spectrum of Ne-water is analogous to that of Ar-water. The Ne-water PES is much shallower than that Ar-water. As a result, there are fewer number of internal rotor states supported by the surface. Indeed, only the π 110 gets Σ 101, Σ 110 gets π 101, n=1, Σ 000 gets Σ 000, and π 111 gets Σ 000 bands were

  3. Line Identifications and Preliminary Synthesis of High-resolution Infrared Spectra of CP and Herbig Ae Stars

    NASA Astrophysics Data System (ADS)

    Cowley, Charles R.; Castelli, F.; Hubrig, S.; Wolff, B.; Elkin, V.

    2012-01-01

    We report on surveys of infrared spectra of chemically peculiar and Herbig Ae stars based on CRIRES (Kaufl, et al. SPIE, 5492, 1218 2004). We discuss the magnetic CP stars Gamma Equ and HD 154708, and multiple-phase observations of the Herbig Ae star HD 101412. The Be star HR 4537 and HgMn HR 6620 were also examined. The primary emphasis of the present work is on line identifications primarily in four regions, 1065-1091, 1084-1109,1550-1587, and 2276-2313nm (with order gaps). Observations were reduced with recipes available from the ESO CRIRES data reduction pipeline. Wavelength calibration is determined from daytime ThAr arc lamp exposures. Generally speaking, this is not rich in atomic lines. The strongest features are the Paschen line P6 (1093.81nm), and He I (108.30nm). The latter shows phase variations indicative of a more complex magnetic field than that of a pure dipole. No individual molecular lines were found in these early stars, though CO emission from circumstellar material is likely present in HR 4537 and HD 101412. We used atomic line lists from Kurucz's site (kurucz.harvard.edu) and VALD (http://vald.astro.univie.ac.at/ cf. Kupka et al. 1999, A&AS, 138, 119), supplemented by Outred (J. Phys. Chem. Ref. Data 7, 1, 1978). The following spectra were identified in Gamma Equ: C I, Si I, Ca I, Mg I, II, Cr I, Fe I, Sr II, and Ce III (1584.75nm). The Ap star spectra show broad Zeeman patterns compatible with published models and field strengths. Synthetic calculations used SYNTHE and SYNTHMAG (Piskunov N. E., 1999, in Astrophys. Space Sci. Library Vol. 243, Solar polarization. Kluwer, p 515). The γ Equ model is from Heiter et al. (2002, A&A, 392, 619). and the line list from VALD.

  4. High-resolution Visible Spectra of Titan

    NASA Astrophysics Data System (ADS)

    Sim, Chae Kyung; Kim, S.

    2006-09-01

    We have obtained high-resolution (R 30,000) spectra of Titan between 4,000 and 10,000 A on Feb. 23, 2005 (UT) using an optical echelle spectrograph (BOES) on the 1.8-m telescope at Bohyunsan Observatory, Korea. The raw Titan spectra contain telluric and solar absorption/emission lines. We used Kitt Peak solar atlases to remove the solar lines effectively. We also constructed synthetic spectra for the atmosphere of Titan including haze layers and utilizing laboratory spectra of CH4 available in literature. Preliminary results on the identifications of weak CH4 lines and on the derived opacities of the haze layers will be presented. Since the observations were carried out near the activities of Cassini observations of Titan, these high-resolution visible spectra are complementary to Cassini/VIMS imagery.

  5. High-resolution mid-infrared spectra of Co II, Ni I, and Fe II in SN 1987A

    NASA Technical Reports Server (NTRS)

    Jennings, D. E.; Boyle, R. J.; Wiedemann, G. R.; Moseley, S. H.

    1993-01-01

    Ground-based infrared observations of SN 1987A on day 612 after the explosion have yielded resolved line profiles of Co II, Ni I, Fe II at 10.52, 11.31, and 17.94 micron, respectively. The spectra were taken at a resolving power of about 1000 with an array grating spectrometer on the 4 m telescope of Cerro Tololo Inter-American Observatory. Based on the observed line intensities we have estimated the minimum mass of each ion: M(Co II) = (6.0 +/- 1.8) x 10 exp -5 solar mass; M(Ni I) = (1.1 +/- 0.1) x 10 exp -3 solar mass; and M(Fe II) = (8.0 +/- 1.5) x 10 exp -3 solar mass. From these we infer total masses for cobalt, nickel, and iron in the ejecta. The nickel and iron line profiles are markedly asymmetric. We interpret these as arising from two components, one centered on the stellar rest velocity with an approximately 3250 km/s full width, and the second at about +1200 km/s with an approximately 1100 km/s full width. The asymmetry may represent a large-scale fracturing of the ejecta by Rayleigh-Taylor instabilities.

  6. Deriving the Extinction to Young Stellar Objects using [Fe II] Near-infrared Emission Lines: Prescriptions from GIANO High-resolution Spectra

    NASA Astrophysics Data System (ADS)

    Pecchioli, T.; Sanna, N.; Massi, F.; Oliva, E.

    2016-07-01

    The near-infrared (NIR) emission lines of Fe+ at 1.257, 1.321, and 1.644 μm share the same upper level; their ratios can then be exploited to derive the extinction to a line emitting region once the relevant spontaneous emission coefficients are known. This is commonly done, normally from low-resolution spectra, in observations of shocked gas from jets driven by Young Stellar Objects. In this paper we review this method, provide the relevant equations, and test it by analyzing high-resolution (R ∼ 50,000) NIR spectra of two young stars, namely the Herbig Be star HD 200775 and the Be star V1478 Cyg, which exhibit intense emission lines. The spectra were obtained with the new GIANO echelle spectrograph at the Telescopio Nazionale Galileo. Notably, the high-resolution spectra allowed checking the effects of overlapping telluric absorption lines. A set of various determinations of the Einstein coefficients are compared to show how much the available computations affect extinction derivation. The most recently obtained values are probably good enough to allow reddening determination within 1 visual mag of accuracy. Furthermore, we show that [Fe ii] line ratios from low-resolution pure emission-line spectra in general are likely to be in error due to the impossibility to properly account for telluric absorption lines. If low-resolution spectra are used for reddening determinations, we advice that the ratio 1.644/1.257, rather than 1.644/1.321, should be used, being less affected by the effects of telluric absorption lines.

  7. High Resolution Wavenumber Standards for the Infrared. (IUPAC Recommendations 1995)

    NASA Technical Reports Server (NTRS)

    Guelachvili, G.; Birk, M.; Borde, C. J.; Brault, J. W.; Brown, L. R.; Carli, B.; Cole, A. R. H.; Evenson, K. M.; Fayt, A.; Hausamann, D.; Johns, J. W. C.; Kauppinen, J.; Kou, Q.; Maki, A. G.; Rao, K. N.; Toth, R. A.; Urban, W.; Valentin, A.; Verges, J.; Wagner, G.; Wappelhorst, M. H.; Wells, J. S.; Winnewisser, B. P.; Winnewisser, M.

    1995-01-01

    The calibration of high resolution infrared spectra is generally more precise than accurate. This is the case even when they are recorded with Fourier transform interferometers. This presentation aims at improving the accuracy of wavenumber measurements in the infrared by recommending a selection of spectral lines as wavenumber standards for absolute calibration.

  8. Upper limits for stratospheric H2O2 and HOCl from high resolution balloon-borne infrared solar absorption spectra

    NASA Technical Reports Server (NTRS)

    Larsen, J. C.; Rinsland, C. P.; Goldman, A.; Murcray, D. G.; Murcray, F. J.

    1985-01-01

    Solar absorption spectra from two stratospheric balloon flights have been analyzed for the presence of H2O2 and HOCl absorption in the 1230.0 to 1255.0 per cm region. The data were recorded at 0.02 per cm resolution during sunset with the University of Denver interferometer system on October 27, 1978 and March 23, 1981. Selected spectral regions were analyzed with the technique of nonlinear least squares spectral curve fitting. Upper limits of 0.33 ppbv for H2O2 and 0.36 ppbv for HOCl near 28 km are derived from the 1978 flight data while upper limits of 0.44 ppbv for H2O2 and 0.43 ppbv for HOCl at 29.5 km are obtained from the 1981 flight data.

  9. Rotational Analysis of Bands in the High-Resolution Infrared Spectra of cis,cis- and trans,trans-1,4-difluorobutadiene-2-d1

    SciTech Connect

    Craig, Norman C.; Easterday, Clay C.; Nemchick, Deacon J.; Williamson, Drew; Sams, Robert L.

    2012-02-01

    Pure samples of cis,cis- and trans,trans-1,4-difluorobutadiene-2-d1 have been synthesized, and high-resolution (0.0015 cm-1) infrared spectra have been recorded for these nonpolar molecules in the gas phase. For the cis,cis isomer, the rotational structure in two C-type bands at 775 and 666 cm-1 and one A-type band at 866 cm-1 has been analyzed to yield a combined set of 2020 ground state combination differences (GSCDs). Ground state rotational constants fit to these GSCDs are A0 = 0.4195790(4), B0 = 0.0536508(8), and C0 = 0.0475802(9) cm-1. For the trans,trans isomer, three Ctype bands at 856, 839, and 709 cm-1 have been investigated to give a combined set of 1624 GSCDs. Resulting ground state rotational constants for this isomer are A0 = 0.9390117(8), B0 = 0.0389225(4), and C0 = 0.0373778(3) cm-1. Small inertial defects confirm the planarity of both isomers in the ground state. Upper state rotational constants have been determined for most of the transitions. The ground state rotational constants for the two isotopologues will contribute to the data set needed for determining semiexperimental equilibrium structures for the nonpolar isomers of 1,4- difluorobutadiene.

  10. High Resolution Wavenumber Standards for the Infrared. (IUPAC Recommendations 1995)

    NASA Technical Reports Server (NTRS)

    Guelachvili, G.; Birk, M.; Bord, C.; Brault, J.; Brown, L.; Carli, B.; Cole, A.; Evenson, D.; Fayt, A.; Hausamann, D.; Johns, J.; Kauppinen, J.; Kou, Q.; Maki, A.; Narahari Rao, K.; Toth, R.; Urban, W.; Valentin, A.; Vergs, J.; Wagner, G.; Winnewisser, B.; Winnewisser, M.

    1995-01-01

    The calibration of high resolution infrared spectra is generally more precise than accurate even when they are recorded with Fourier interferometers. In order to improve the consistency of the spectral measurements, an IUPAC project has been undertaken. Its aim was to recommend a selection of spectral lines as wavenumber standards for absolute calibration in the infrared. This paper will report the final recommendations in the spectral range extending from about 4 to about 7000 cm(be).

  11. Rotational Analysis of Bands in the High-Resolution Infrared Spectra of trans,trans- and cis,cis-1,4-DIFLUOROBUTADIENE-2-d1

    NASA Astrophysics Data System (ADS)

    Craig, Norman C.; Nemchick, Deacon J.; Easterday, Clay C.; Glor, Ethan C.; Williamson, Drew F. K.; Blake, Thomas A.; Sams, Robert L.

    2010-06-01

    Ground state rotational constants for a series of isotopomers are being sought for use in determining the semi-experimental equilibrium structures of the isomers of 1,4-difluorobutadiene. Because fluorine substitution has a large influence on CC bond lengths in C3 and C4 rings, we asked how fluorine substitution affects butadiene. trans,trans- and cis,cis-1,4-Difluorobutadiene-2-d1 have been synthesized, and high-resolution (0.0013 cm-1) infrared spectra have been recorded for these nonpolar species. Analysis of the rotational structure in several bands is reported. For the trans,trans isomer, the C-type band at 709.0 cm-1 for ν 21(a^") has been fully analyzed, and the C-type band at 914.3 cm-1 for ν 18(a^") has been partially analyzed. Interfering with the analysis of the second band is overlap of its R branch with the P branch of the A/B-type band for ν 13(a^') at 933 cm-1. For the cis,cis isomer, as much as possible of the C-type band (K_a^' = 10 to 34) for ν 20(a^") at 775.4 cm-1 has been analyzed. An A-type band for ν 13(a^') at 865.8 cm-1 has also been analyzed into the band center. Small inertial defects confirm that these molecules are planar. Ground state rotational constants are reported for both isomers in comparison with those for the normal species. N. C. Craig, M. C. Moore, C. F. Neese, D. C. Oertel, L. Pedraza, and T. Masiello, J. Mol. Spectrosc. 254, 39-46 (2009).

  12. Reinvestigation of the microwave and new high resolution far-infrared spectra of cis-methyl nitrite, CH 3ONO: Rotational study of the two first torsional states

    NASA Astrophysics Data System (ADS)

    Sironneau, V.; Chelin, P.; Tchana, F. Kwabia; Kleiner, I.; Pirali, O.; Roy, P.; Guillemin, J.-C.; Orphal, J.; Margulès, L.; Motiyenko, R. A.; Cooke, S. A.; Youngblood, W. J.; Agnew, A.; Dewberry, C. T.

    2011-05-01

    The first far-infrared high resolution absorption measurement of the cis-methyl nitrite molecule has been recorded in the range 15-400 cm -1 using the synchrotron AILES beamline radiation at SOLEIL with a resolution of 0.0011 cm -1. First assignments for the pure rotational transitions (15-65 cm -1) belonging to the ground ν t (= ν15) = 0 and first ν t = 1 excited torsional state are based on measurements from previous studies performed in the 13-40 GHz spectral range, as well as on new millimeter-wave measurements performed at Lille in the spectral range 75-465 GHz. A few measurements and remeasurements in the 1.8-13 GHz were also performed using the chirped FT-MW spectrometer located in North Texas. The pure rotational transitions in the far-infrared and in the microwave spectral range belonging to the two first torsional states have been globally fitted using the RAM ("Rho Axis Method") dealing with the rotation-torsion Hamiltonian and implemented in the BELGI code. A total of 708 and 713 microwave transitions (6 ⩽ J ⩽ 40, Kamax ⩽ 23) belonging to the ground torsional state ν t = 0 and 1 have been fitted with root-mean-square (rms) deviations of 37.4 kHz and 32.3 kHz respectively, and 3170 pure rotational transitions in the far-infrared range (12 ⩽ J max ⩽ 65, 0 ⩽ Kamax ⩽ 48) belonging to ν t = 0 and 1 have been fitted with a rms deviation of 0.00017 cm -1, using 35 parameters. Since in the far-infrared spectral range, the A-E internal rotor splittings have not been observed for the transitions belonging to the torsional ground ν t = 0 state of the cis-methyl nitrite species, another fit was performed on those lines, using a Watson type Hamiltonian for comparison.

  13. Metallicity determination of M dwarfs. High-resolution infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Lindgren, Sara; Heiter, Ulrike; Seifahrt, Andreas

    2016-02-01

    Context. Several new techniques to determine the metallicity of M dwarfs with better precision have been developed over the last decades. However, most of these studies were based on empirical methods. In order to enable detailed abundance analysis, standard methods established for warmer solar-like stars, i.e. model-dependent methods using fitting of synthetic spectra, still need to be used. Aims: In this work we continue the reliability confirmation and development of metallicity determinations of M dwarfs using high-resolution infrared spectra. The reliability was confirmed through analysis of M dwarfs in four binary systems with FGK dwarf companions and by comparison with previous optical studies of the FGK dwarfs. Methods: The metallicity determination was based on spectra taken in the J band (1.1-1.4 μm) with the CRIRES spectrograph. In this part of the infrared, the density of stellar molecular lines is limited, reducing the amount of blends with atomic lines enabling an accurate continuum placement. Lines of several atomic species were used to determine the stellar metallicity. Results: All binaries show excellent agreement between the derived metallicity of the M dwarf and its binary companion. Our results are also in good agreement with values found in the literature. Furthermore, we propose an alternative way to determine the effective temperature of M dwarfs of spectral types later than M2 through synthetic spectral fitting of the FeH lines in our observed spectra. Conclusions: We have confirmed that a reliable metallicity determination of M dwarfs can be achieved using high-resolution infrared spectroscopy. We also note that metallicites obtained with photometric metallicity calibrations available for M dwarfs only partly agree with the results we obtain from high-resolution spectroscopy. Based on data obtained at ESO-VLT, Paranal Observatory, Chile, Program ID 082.D-0838(A) and 084.D-1042(A).

  14. Use of high-resolution measurements for the retrieval of temperature and gas-concentration profiles from outgoing infrared spectra in the presence of cirrus clouds.

    PubMed

    Huang, Xianglei L; Yung, Yuk L; Margolis, Jack S

    2003-04-20

    We explore ways in which high-spectral-resolution measurements can aid in the retrieval of atmospheric temperature and gas-concentration profiles from outgoing infrared spectra when optically thin cirrus clouds are present. Simulated outgoing spectra that contain cirrus are fitted with spectra that do not contain cirrus, and the residuals are examined. For those lines with weighting functions that peak near the same altitude as the thin cirrus, unique features are observed in the residuals. These unique features are highly sensitive to the resolution of the instrumental line shape. For thin cirrus these residual features are narrow (< or = 0.1 cm(-1)), so high spectral resolution is required for unambiguous observation. The magnitudes of these unique features are larger than the noise of modern instruments. The sensitivities of these features to cloud height and cloud optical depth are also discussed. Our sensitivity studies show that, when the errors in the estimation of temperature profiles are not large, the dominant contribution to the residuals is the misinterpretation of cirrus. An analysis that focuses on information content is also presented. An understanding of the magnitude of the effect and of its dependence on spectral resolution as well as on spectral region is important for retrieving spacecraft data and for the design of future infrared instruments for forecasting weather and monitoring greenhouse gases. PMID:12716157

  15. On the Assessment and Uncertainty of Atmospheric Trace Gas Burden Measurements with High Resolution Infrared Solar Occultation Spectra from Space by the ATMOS Experiment

    NASA Technical Reports Server (NTRS)

    Abrams, M. C.; Chang, A. Y.; Gunson, M. R.; Abbas, M. M.; Goldman, A.; Irion, F. W.; Michelsen, H. A.; Newchurch, M. J.; Rinsland, C. P.; Stiller, G. P.; Zander, R.

    1996-01-01

    The Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument is a high resolution Fourier transform spectrometer that measures atmospheric composition from low Earth orbit with infrared solar occultation sounding in the limb geometry. Following an initial flight in 1985, ATMOS participated in the Atmospheric Laboratory for Applications and Science (ATLAS) 1, 2, and 3 Space Shuttle missions in 1992, 1993, and 1994 yielding a total of 440 occultation measurements over a nine year period. The suite of more than thirty atmospheric trace gases profiled includes CO2, O3, N2O, CH4, H2O, NO, NO2, HNO3, HCl, HF, ClONO2, CCl3F, CCl2F2, CHF2Cl, and N2O5. The analysis method has been revised throughout the mission years culminating in the 'version 2' data set. The spectroscopic error analysis is described in the context of supporting the precision estimates reported with the profiles; in addition, systematic uncertainties assessed from the quality of the spectroscopic database are described and tabulated for comparisons with other experiments.

  16. High-Resolution Vibrational Spectra of Furazan

    NASA Astrophysics Data System (ADS)

    Stiefvater, Otto L.

    1991-10-01

    The study by Fourier transform (FT) infrared (IR) spectroscopy of the fundamental vibrational bands v12 and v5 of furazan yields the origins of these bands with a statistical uncertainty of 10-6 cm-1, which leads to an estimated absolute uncertainty of 10-4 cm-1. The values are v°12 = 952.6123 cm -1 and v°5 = 1.005.3536 cm -1. They confirm the values previously deduced from laser/microwave double resonance (LMDR) experiments. Previous results for the molecular constants of the vibrational ground state and of the two vibrationally excited states, as obtained by double resonance modulation (DRM) microwave spectroscopy alone, are confirmed and refined. Advantages brought about through the combination of the DRM microwave and the FT-IR technique are outlined.

  17. Analysis of the rotational structure in the high-resolution infrared spectra of trans-hexatriene-2-d1 and -3-d1

    SciTech Connect

    Craig, Norman C.; Chen, Yihui; van Besien, Herman; Blake, Thomas A.

    2014-09-01

    The 2-d1 and 3-d1 isotopologues of trans-hexatriene have been synthesized, and their high-resolution (0.0015 cm-1) IR spectra have been recorded. For each of the isotopologues the rotational structure in four C-type bands for out-of-plane vibrational modes has been analyzed, and the ground state combination differences (GSCDs) have been pooled. Ground state rotational constants have been fitted to the GSCDs. For the 2-d species, A0, B0, and C0 values of 0.7837254(5), 0.0442806(3), and 0.0419299(2) cm-1 were fitted to 2450 GSCDs. For the 3-d species, A0, B0, and C0 values of 0.7952226(8), 0.0446149(7), and 0.0422661(4) cm-1 were fitted to 2234 GSCDs. For the eleven out-of-plane modes of the two isotopologues, predictions of anharmonic wavenumbers and harmonic intensities have been computed and compared with experiment where possible.

  18. High Resolution Infrared Spectra of the v2, v3, v4 and 2v3 Bands of 32S16O3

    SciTech Connect

    Maki, Arthur G.; Blake, Thomas A.; Sams, Robert L.; Vulpanovici, Nicolae; Barber, Jeffrey B.; Chrysostom, Engelene; Masiello, Tony; Nibler, Joseph W.; Weber, Alfons

    2001-09-14

    New measurements are reported for the infrared spectrum of sulfur trioxide, 32S16O3, with resolutions ranging from 0.0015 cm-1 to 0.0025 cm-1. New rovibrational constants have been measured for the fundamentals v2, v3, and v4, and the overtone band 2v3. Comparisons are made with the earlier high resolution measurements on SO3 and the high correlation among some of the constants related to the Coriolis coupling of the v2 and v4 levels is duscussed in order to understand the areas of disagreement with the arlier work. Splittings of some of the levels are observed and hte splitting constant for K = 3 of the ground state is determined for the first time. Other observed splittings include the K = 1 levels of 2v3 (I = 2), the K = 2 levels of the v3 and v4 states and the K = 3 levels of v2. This analysis shows that there are level corssings between the I = 0 and I = 2 states of 2v3 that allow one to determine the separation of the sub-band centers for those two states even thoug the I = o state is a dark state. This is a generalized phenomenon that should be found for many other molecules with the same symmetry. The I-type resonance constant that couples the I = 0 and 2 states is roughly the same as q3 which causes the splitting of the I = 1 levels of the v3 fundamental.

  19. High-resolution near-infrared spectroscopy of water dimer

    NASA Technical Reports Server (NTRS)

    Huang, Z. S.; Miller, R. E.

    1989-01-01

    High-resolution near-infrared spectra are reported for all of the O-H stretch vibrational bands of the water dimer. The four O-H vibrations are characterized as essentially independent proton-donor or proton-acceptor motions. In addition to the rotational and vibrational information contained in these spectra, details are obtained concerning the internal tunneling dynamics in both the ground and excited vibrational states. These results show that, for tunneling motions which involve the interchange of the proton donor and acceptor molecules, the associated frequencies decrease substantially due to vibrational excitation. The predissociation lifetimes for the various states of the dimer are determined from linewidth measurements. These results clearly show that the predissociation dynamics is strongly dependent on the tunneling states, as well as the Ka quantum number, indicating that the internal tunneling dynamics plays an important role in determining the dissociation rate in this complex.

  20. High resolution infrared and Raman spectra of {sup 13}C{sup 12}CD{sub 2}: The CD stretching fundamentals and associated combination and hot bands

    SciTech Connect

    Di Lonardo, G.; Fusina, L. Canè, E.; Tamassia, F.; Martínez, R. Z.; Bermejo, D.

    2015-09-07

    Infrared and Raman spectra of mono {sup 13}C fully deuterated acetylene, {sup 13}C{sup 12}CD{sub 2}, have been recorded and analysed to obtain detailed information on the C—D stretching fundamentals and associated combination, overtone, and hot bands. Infrared spectra were recorded at an instrumental resolution ranging between 0.006 and 0.01 cm{sup −1} in the region 1800–7800 cm{sup −1}. Sixty new bands involving the ν{sub 1} and ν{sub 3} C—D stretching modes also associated with the ν{sub 4} and ν{sub 5} bending vibrations have been observed and analysed. In total, 5881 transitions have been assigned in the investigated spectral region. In addition, the Q branch of the ν{sub 1} fundamental was recorded using inverse Raman spectroscopy, with an instrumental resolution of about 0.003 cm{sup −1}. The transitions relative to each stretching mode, i.e., the fundamental band, its first overtone, and associated hot and combination bands involving bending states with υ{sub 4} + υ{sub 5} up to 2 were fitted simultaneously. The usual Hamiltonian appropriate to a linear molecule, including vibration and rotation l-type and the Darling–Dennison interaction between υ{sub 4} = 2 and υ{sub 5} = 2 levels associated with the stretching states, was adopted for the analysis. The standard deviation for each global fit is ≤0.0004 cm{sup −1}, of the same order of magnitude of the measurement precision. Slightly improved parameters for the bending and the ν{sub 2} manifold have been also determined. Precise values of spectroscopic parameters deperturbed from the resonance interactions have been obtained. They provide quantitative information on the anharmonic character of the potential energy surface, which can be useful, in addition to those reported in the literature, for the determination of a general anharmonic force field for the molecule. Finally, the obtained values of the Darling–Dennison constants can be valuable for understanding energy flows

  1. High resolution infrared spectra of the ν1- ν4 bands of BiH 3, and ab initio calculations of the spectroscopic parameters

    NASA Astrophysics Data System (ADS)

    Jerzembeck, Wolfgang; Bürger, Hans; Breidung, Jürgen; Thiel, Walter

    2004-07-01

    The infrared spectrum of short-lived BiH 3 has been studied by Fourier transform technique. The BiH stretching bands ν1/ ν3 at 1733.2546/1734.4671 cm -1 and the bending fundamentals ν2/ ν4 at 726.6992/751.2385 cm -1 have been measured with a resolution of 5.5 and 6.6 × 10 -3 cm -1, respectively. The spectra were analyzed using different reductions of the rovibrational Hamiltonian accounting for the numerous resonance interactions in particular within the strongly Coriolis-coupled bending dyad. About 1150 and 980 transitions belonging to the ν1/ ν3 and ν2/ ν4 bands were fitted with an rms deviation of 0.62 and 0.53 × 10 -3 cm -1, respectively. High-level ab initio calculations at the coupled cluster CCSD(T) level with an energy-consistent small-core pseudopotential and large basis sets were carried out to determine the equilibrium structure, the anharmonic force field, and the associated spectroscopic constants of BiH 3. The theoretical results are in good agreement with the available experimental data.

  2. High-resolution studies of atmospheric IR emission spectra

    NASA Technical Reports Server (NTRS)

    Murcray, F. J.; Murcray, F. H.; Goldman, A.; Blatherwick, R. D.; Murcray, D. G.

    1991-01-01

    Atmospheric emission spectra obtained with two different spectrometer systems are presented. The first system (the BOMEM Michelson interferometer) is designed for emission work. Spectra were obtained under adverse conditions in the Antarctic, and are still of good absolute accuracy. The second system (a modified Bruker Instruments IFS120 very high spectral resolution interferometer) demonstrates the sensitivity that can be achieved even at higher spectral resolution. This system shows that mid-IR atmospheric emission spectra can be obtained with a good SNR in a reasonable length of time at a relatively high resolution. A properly designed high resolution system should achieve high accuracy, sensitivity, and resolution, thereby permitting measurements of many atmospheric constituents when solar spectra cannot be obtained.

  3. Simulation and fitting of high resolution Rutherford backscattering spectra

    NASA Astrophysics Data System (ADS)

    Borschel, Christian; Schnell, Martin; Ronning, Carsten; Hofsäss, Hans

    2009-05-01

    A computer program for the analysis of high resolution Rutherford backscattering spectra (HR-RBS), which can be recorded with an electrostatic energy analyzer (ESA) and a resolution of about 1 keV, has been developed. The use of an ESA results in various differences compared to conventional RBS spectra, motivating the development of a new algorithm for simulation for these spectra. We present a Monte Carlo based diffusion-like fit approach for evaluation of the HR-RBS spectra, which is in particular useful for fitting concentration gradients. Examples for the application of the algorithm are shown to demonstrate its functionality.

  4. High Resolution Mass Spectra Analysis with a Programmable Calculator.

    ERIC Educational Resources Information Center

    Holdsworth, David K.

    1980-01-01

    Highlighted are characteristics of programs written for a pocket-sized programmable calculator to analyze mass spectra data (such as displaying high resolution masses for formulas, predicting whether formulas are stable molecules or molecular ions, determining formulas by isotopic abundance measurement) in a laboratory or classroom. (CS)

  5. High-Resolution Vibrational Spectra of Furazan II. The B1 Fundamental ν 11 at ~ 1175 cm-1 from Fourier-Transform Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Stiefvater, Otto L.

    1992-03-01

    The high-resolution FT-IR spectrum of the A-type fundamental ν11 of furazan ( C2H2N20) has been recorded and analysed against the background of rotational information from DRM microwave spectroscopy to yield the band origin as ν110= 1175.3377 + 0.0001 cm-1 . The combined use of microwave (MW) and FT-IR data gives this band origin with a statistical uncertainty of σ= 10-6cm-1 and leads to a refinement of the rotational constants of the state ν11 = 1 over those derivable from either MW or FT-IR data alone

  6. High Resolution Optical and NIR Spectra of HBC 722

    NASA Astrophysics Data System (ADS)

    Lee, Jeong-Eun; Park, Sunkyung; Green, Joel D.; Cochran, William D.; Kang, Wonseok; Lee, Sang-Gak; Sung, Hyun-Il

    2015-07-01

    We present the results of high resolution (R ≥ 30,000) optical and near-IR spectroscopic monitoring observations of HBC 722, a recent FU Orionis object that underwent an accretion burst in 2010. We observed HBC 722 in the optical/near-IR with the Bohyunsan Optical Echelle Spectrograph, Hobby–Eberly Telescope-HRS, and Immersion Grating Infrared Spectrograph, at various points in the outburst. We found atomic lines with strongly blueshifted absorption features or P Cygni profiles, both evidence of a wind driven by the accretion. Some lines show a broad double-peaked absorption feature, evidence of disk rotation. However, the wind-driven and disk-driven spectroscopic features are anti-correlated in time; the disk features became strong as the wind features disappeared. This anti-correlation might indicate that the rebuilding of the inner disk was interrupted by the wind pressure during the first 2 years. The half-width at half-depth of the double-peaked profiles decreases with wavelength, indicative of the Keplerian rotation; the optical spectra with the disk feature are fitted by a G5 template stellar spectrum convolved with a rotation velocity of 70 km s‑1 while the near-IR disk features are fitted by a K5 template stellar spectrum convolved with a rotation velocity of 50 km s‑1. Therefore, the optical and near-IR spectra seem to trace the disk at 39 and 76 R⊙, respectively. We fit a power-law temperature distribution in the disk, finding an index of 0.8, comparable to optically thick accretion disk models. Based on observations obtained with the Hobby–Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.

  7. High Resolution Optical and NIR Spectra of HBC 722

    NASA Astrophysics Data System (ADS)

    Lee, Jeong-Eun; Park, Sunkyung; Green, Joel D.; Cochran, William D.; Kang, Wonseok; Lee, Sang-Gak; Sung, Hyun-Il

    2015-07-01

    We present the results of high resolution (R ≥ 30,000) optical and near-IR spectroscopic monitoring observations of HBC 722, a recent FU Orionis object that underwent an accretion burst in 2010. We observed HBC 722 in the optical/near-IR with the Bohyunsan Optical Echelle Spectrograph, Hobby-Eberly Telescope-HRS, and Immersion Grating Infrared Spectrograph, at various points in the outburst. We found atomic lines with strongly blueshifted absorption features or P Cygni profiles, both evidence of a wind driven by the accretion. Some lines show a broad double-peaked absorption feature, evidence of disk rotation. However, the wind-driven and disk-driven spectroscopic features are anti-correlated in time; the disk features became strong as the wind features disappeared. This anti-correlation might indicate that the rebuilding of the inner disk was interrupted by the wind pressure during the first 2 years. The half-width at half-depth of the double-peaked profiles decreases with wavelength, indicative of the Keplerian rotation; the optical spectra with the disk feature are fitted by a G5 template stellar spectrum convolved with a rotation velocity of 70 km s-1 while the near-IR disk features are fitted by a K5 template stellar spectrum convolved with a rotation velocity of 50 km s-1. Therefore, the optical and near-IR spectra seem to trace the disk at 39 and 76 R⊙, respectively. We fit a power-law temperature distribution in the disk, finding an index of 0.8, comparable to optically thick accretion disk models. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.

  8. Analysis of the rotational structure in the high-resolution infrared spectra of cis,cis- and trans,trans-1,4-difluorobutadiene-1-d1 and trans,trans-1,4-difluorobutadiene-1,4-d2

    SciTech Connect

    Craig, Norman C.; Chen, Yihui; Lu, Yuhua; Neese, Christopher F.; Nemchick, Deacon J.; Blake, Thomas A.

    2013-06-01

    Samples of cis,cis- and trans,trans-1,4-difluorobutadiene-1- d1 and of trans,trans-1,4-difluorobutadiene-1,4-d2 have been synthesized, and high-resolution (≤0.0018 cm-1) infrared spectra of these substances have been recorded in the gas phase. Analysis of the rotational structure, mostly in C-type bands, has yielded ground state rotational constants. For the two 1-d1 species more than one band has been analyzed. For the 1,4-d2 species only one band was available for analysis. However, good agreement between the experimental centrifugal distortion constants and those predicted with a B3LYP/cc-pVTZ model give strong support to the analysis of the very dense spectrum. The ground state rotational constants are a contribution to finding semiexperimental equilibrium structures of the two nonpolar isomers of 1,4- difluorobutadiene.

  9. High-Resolution Vibrational Spectra of Furazan IV. The Aj Fundamental v2 at ~ 1418 cm-1 from Fourier-Transform Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Stiefvater, Otto L.; Klee, Stefan

    1993-06-01

    The band origin of the A1 mode v2 , which represents the symmetrical stretching vibration of the two C = N bonds of furazan, has been determined from the high-resolution FT-IR band as v20 = 1418.4724± 0.0001 cm-1. The rotational parameters of this excited state, as determined in a preceding DRM microwave study, have been confirmed and their precision was raised through the combined fit of microwave data and of some 2500 rovibrational transitions. The use of conjugate low-J Q-branch lines for the determination of the origin of a B-type IR band of an asymmetric rotor is illustrated.

  10. A reevaluation of the assignment of the vibrational fundamentals and the rotational analysis of bands in the high-resolution infrared spectra of trans- and cis- 1,3,5-hexatriene

    SciTech Connect

    Craig, Norman C.; Leyden, Matthew C.; Moore, Michael C.; Patchen, Amie K.; van den Heuvel, Titus; Blake, Thomas A.; Masiello, Tony; Sams, Robert L.

    2010-07-01

    Assignments of the vibrational fundamentals of cis- and trans-1,3,5-hexatriene are reevaluated with new infrared and Raman spectra and with quantum chemical predictions of intensities and anharmonic frequencies. The rotational structure is analyzed in the high-resolution (0.0013-0.0018 cm -1) infrared spectra of three C-type bands of the trans isomer and two C-type bands of the cis isomer. The bands for the trans isomer are at 1010.96 cm-1 (v14), 900.908 cm-1 (v16), and 683.46 cm-1 (v17). Ground state (GS) rotational constants have been fitted to the combined ground state combination differences (GSCDs) for the three bands of the trans isomer. The bands for the cis isomer are at 907.70 cm-1 (v33) and 587.89 cm-1 (v35). GS rotational constants have been fitted to the combined GSCDs for the two bands of the cis isomer and compared with those obtained from microwave spectroscopy. Small inertial defects in the GSs confirm that both molecules are planar. Upper state rotational constants were fitted for all five bands.

  11. Strategies for Interpreting High Resolution Coherent Multidimensional Spectra

    NASA Astrophysics Data System (ADS)

    Wells, Thresa A.; House, Zuri R.; Chen, Peter C.; Strangfeld, Benjamin R.

    2013-06-01

    The electronic spectra of certain molecules can be very complex and consist of a high density of peaks. The high density of peaks results in severe spectral congestion, making conventional data analysis techniques extremely difficult to use. One solution to this problem is to use high resolution coherent 2D spectroscopy (HRC2DS), which can improve resolution and sort peaks into recognizable clusters. This technique requires new data analysis techniques to accurately assign peaks. Even though HRC2DS can improve spectral resolution, some regions of the spectra may still remain congested. The ability to solve this problem using even higher dimensional techniques (e.g., high resolution coherent 3D spectroscopy) with 3D pattern recognition and data analysis techniques will be discussed.

  12. Design and implementation of spaceborne high resolution infrared touch screen

    NASA Astrophysics Data System (ADS)

    Li, Tai-guo; Li, Wen-xin; Dong, Yi-peng; Ma, Wen; Xia, Jia-gao

    2015-10-01

    For the consideration of the special application environment of the electronic products used in aerospace and to further more improve the human-computer interaction of the manned aerospace area. The research is based on the design and implementation way of the high resolution spaceborne infrared touch screen on the basis of FPGA and DSP frame structure. Beside the introduction of the whole structure for the high resolution spaceborne infrared touch screen system, this essay also gives the detail information about design of hardware for the high resolution spaceborne infrared touch screen system, FPGA design, GUI design and DSP algorithm design based on Lagrange interpolation. What is more, the easy makes a comprehensive research of the reliability design for the high resolution spaceborne infrared touch screen for the special purpose of it. Besides, the system test is done after installation of spaceborne infrared touch screen. The test result shows that the system is simple and reliable enough, which has a stable running environment and high resolution, which certainly can meet the special requirement of the manned aerospace instrument products.

  13. Band Selection Procedure for Reduction of High Resolution Spectra

    NASA Astrophysics Data System (ADS)

    Pasztor, L.; Csillag, F.

    In this paper we present a technique for reduction of spectra based on the methods of multivariate statistical analysis. The procedure was developed for general processing of digital, high resolution spectra. The recursive band selection method can be applied in studies for weighting (original) spectral bands according their sensitivity to a predefined classification scheme. Additionally, definition of medium and broad band systems is possible, which can efficiently substitute the original spectrum. According to the characteristics of the method resulted from a remote sensing application (convergence, robustness), it is suggested for use in different (radio, UV, X-ray etc.) astronomical studies as well.

  14. Principal component and sensitivity analysis of cirrus clouds using high-resolution IR radiance spectra: simulations and observations

    NASA Technical Reports Server (NTRS)

    Eldering, A.; Braverman, A.; Fetzer, E. J.

    2003-01-01

    A set of simulated and observed nadir-oriented high-resolution infrared emission spectra of synthetic cirrus clouds is analyzed to assess the spectrally dependent variability of radiance from the adjustment of some microphysical and bulk cirrus cloud properties.

  15. CO2 retrieval algorithm for the thermal infrared spectra of the Greenhouse Gases Observing Satellite: Potential of retrieving CO2 vertical profile from high-resolution FTS sensor

    NASA Astrophysics Data System (ADS)

    Saitoh, Naoko; Imasu, Ryoichi; Ota, Yoshifumi; Niwa, Yosuke

    2009-09-01

    The Greenhouse Gases Observing Satellite (GOSAT) was successfully launched in January 2009, with the aim of providing global observations of greenhouse gases. We developed an algorithm to retrieve CO2 vertical profiles from the terrestrial radiation spectra at 700-800 cm-1 and assessed its validity. For this purpose, we first computed GOSAT pseudomeasurement spectra and then performed CO2 retrieval simulations using the maximum a posteriori (MAP) method, with analytical data for temperature information. Our simulations with no uncertainty in the estimates of atmospheric conditions such as surface temperature, surface emissivity, and profiles of temperature, water vapor, and ozone showed that the retrieved CO2 profiles had an accuracy of 1% above 800 hPa, with little dependence on the a priori profiles. Introducing correlations between layers in an a priori error covariance matrix was important for CO2 retrieval especially above 200 hPa. Enhancing the correlations below 800 hPa was important for CO2 retrieval there. Selecting 100 channels based on CO2 information content for all layers, 10 channels for the region above 55 hPa, and 50 channels for the region below 800 hPa was sufficient to achieve CO2 retrieval with 1% accuracy from the troposphere through the stratosphere. Our simulations with possible errors in the atmospheric conditions showed that 1% accuracy was also achieved at 600-100 hPa in every latitude region, although the retrieved CO2 concentrations probably included up to 4% positive and negative biases at 30°S-30°N above 100 hPa and at mid- and high latitudes below 600 hPa, respectively.

  16. Modeling Titan's thermal infrared spectrum for high-resolution space observations

    NASA Astrophysics Data System (ADS)

    Coustenis, A.; Encrenaz, Th.; Bezard, B.; Bjoraker, G.; Graner, G.; Dang-Nhu, M.; Arie, E.

    1993-04-01

    The observability of minor species in Titan's atmosphere in its infrared thermal range is systematically studied and modeled to generate synthetic spectra. The model results on methane, water vapor, benzene, allene, and other heavier trace molecules are used to illustrate the capabilities of instruments aboard the Infrared Space Observatory, in particular a high-resolution composite infrared spectrometer, to determine vertical distributions of the molecules in a few hours of integration time.

  17. Rotation spectrum and high resolution infrared spectra of the fundamental bands of 121SbD 3. Determination of the ground state and equilibrium structures. Ab initio calculations of the spectroscopic parameters

    NASA Astrophysics Data System (ADS)

    Canè, E.; Di Lonardo, G.; Fusina, L.; Jerzembeck, W.; Bürger, H.; Breidung, J.; Thiel, W.

    2006-01-01

    The high resolution infrared spectrum of 121SbD 3, recorded between 20 and 350 cm -1 and in the regions of bending and stretching fundamental bands, centred at 600 and 1350 cm -1, has been analysed. Splittings of the K″=3, 6 lines have been observed both in the rotation and ro-vibration spectra. A large number of 'perturbation allowed' transitions with selection rules Δ(k-ℓ)=±3, ±6 and ±9 have been identified in all fundamental bands. Accurate ground state molecular parameters have been determined fitting simultaneously the rotational transitions and about 9000 ground state combination differences obtained from lines assigned in the ro-vibrational spectra. The A and B reductions of the rotational Hamiltonian have been applied in the analysis of the ground state. They provided almost equivalent results. The molecular parameters of the 1 1, 2 1, 3 1 and 4 1 states have been obtained from the simultaneous analysis of the ν1 ( A1)/ ν3 ( E) stretching and of the ν2 ( A1)/ ν4 ( E) bending dyads. In fact, the corresponding excited states are affected by strong perturbations due to Coriolis and k-type rovibrational interactions that have been treated explicitly in the model adopted for the analysis. Improved effective ground state and equilibrium geometries have been determined and compared to those of 121SbH 3 and of 123SbD 3. Ab initio calculations at the coupled cluster CCSD(T) level with an energy-consistent large-core pseudopotential and large basis sets have been carried out to determine the equilibrium structure, the anharmonic force field, and the associated spectroscopic constants of 121-stibine. The theoretical constants and structural parameters are in good agreement with the experimental data.

  18. POLLUX: a database of stellar spectra - First step : SED and High Resolution Synthetic Spectra

    NASA Astrophysics Data System (ADS)

    Palacios, A.; Josselin, E.; Lèbre, A.; Martins, F.; Monier, R.; Plez, B.; Belmas, M.

    2008-10-01

    POLLUX is a stellar spectra database under development at the GRAAL laboratory (Montpellier, France). It will be made available on-line to the community through a VO compliant interface (http://pollux.graal.univ-montp2.fr). In its first version, POLLUX will propose theoretical data: high resolution synthetic spectra and spectral energy distribution.

  19. High resolution infrared datasets useful for validating stratospheric models

    NASA Technical Reports Server (NTRS)

    Rinsland, Curtis P.

    1992-01-01

    An important objective of the High Speed Research Program (HSRP) is to support research in the atmospheric sciences that will improve the basic understanding of the circulation and chemistry of the stratosphere and lead to an interim assessment of the impact of a projected fleet of High Speed Civil Transports (HSCT's) on the stratosphere. As part of this work, critical comparisons between models and existing high quality measurements are planned. These comparisons will be used to test the reliability of current atmospheric chemistry models. Two suitable sets of high resolution infrared measurements are discussed.

  20. CASSIS: The Cornell Atlas of Spitzer/Infrared Spectrograph Sources. II. High-resolution Observations

    NASA Astrophysics Data System (ADS)

    Lebouteiller, V.; Barry, D. J.; Goes, C.; Sloan, G. C.; Spoon, H. W. W.; Weedman, D. W.; Bernard-Salas, J.; Houck, J. R.

    2015-06-01

    The Infrared Spectrograph (IRS) on board the Spitzer Space Telescope observed about 15,000 objects during the cryogenic mission lifetime. Observations provided low-resolution (R=λ /{Δ }λ ≈ 60-127) spectra over ≈ 5-38 μm and high-resolution (R≈ 600) spectra over 10-37 μm. The Cornell Atlas of Spitzer/IRS Sources (CASSIS) was created to provide publishable quality spectra to the community. Low-resolution spectra have been available in CASSIS since 2011, and here we present the addition of the high-resolution spectra. The high-resolution observations represent approximately one-third of all staring observations performed with the IRS instrument. While low-resolution observations are adapted to faint objects and/or broad spectral features (e.g., dust continuum, molecular bands), high-resolution observations allow more accurate measurements of narrow features (e.g., ionic emission lines) as well as a better sampling of the spectral profile of various features. Given the narrow aperture of the two high-resolution modules, cosmic ray hits and spurious features usually plague the spectra. Our pipeline is designed to minimize these effects through various improvements. A super-sampled point-spread function was created in order to enable the optimal extraction in addition to the full aperture extraction. The pipeline selects the best extraction method based on the spatial extent of the object. For unresolved sources, the optimal extraction provides a significant improvement in signal-to-noise ratio over a full aperture extraction. We have developed several techniques for optimal extraction, including a differential method that eliminates low-level rogue pixels (even when no dedicated background observation was performed). The updated CASSIS repository now includes all the spectra ever taken by the IRS, with the exception of mapping observations.

  1. High resolution infrared acquisitions droning over the LUSI mud eruption.

    NASA Astrophysics Data System (ADS)

    Di Felice, Fabio; Romeo, Giovanni; Di Stefano, Giuseppe; Mazzini, Adriano

    2016-04-01

    The use of low-cost hand-held infrared (IR) thermal cameras based on uncooled micro-bolometer detector arrays became more widespread during the recent years. Thermal cameras have the ability to estimate temperature values without contact and therefore can be used in circumstances where objects are difficult or dangerous to reach such as volcanic eruptions. Since May 2006 the Indonesian LUSI mud eruption continues to spew boiling mud, water, aqueous vapor, CO2, CH4 and covers a surface of nearly 7 km2. At this locality we performed surveys over the unreachable erupting crater. In the framework of the LUSI Lab project (ERC grant n° 308126), in 2014 and 2015, we acquired high resolution infrared images using a specifically equipped remote-controlled drone flying at an altitude of m 100. The drone is equipped with GPS and an autopilot system that allows pre-programming the flying path or designing grids. The mounted thermal camera has peak spectral sensitivity in LW wavelength (μm 10) that is characterized by low water vapor and CO2 absorption. The low distance (high resolution) acquisitions have a temperature detail every cm 40, therefore it is possible to detect and observe physical phenomena such as thermodynamic behavior, hot mud and fluids emissions locations and their time shifts. Despite the harsh logistics and the continuously varying gas concentrations we managed to collect thermal images to estimate the crater zone spatial thermal variations. We applied atmosphere corrections to calculate infrared absorption by high concentration of water vapor. Thousands of images have been stitched together to obtain a mosaic of the crater zone. Regular monitoring with heat variation measurements collected, e.g. every six months, could give important information about the volcano activity estimating its evolution. A future data base of infrared high resolution and visible images stored in a web server could be a useful monitoring tool. An interesting development will be

  2. High Resolution Far-Infrared Spectra of Thiophosgene with a Synchrotron Source: The nu{sub 2} and nu{sub 4} Bands Near 500 cm{sup -1}

    SciTech Connect

    McKellar, A. R. W.; Billinghurst, B. E.

    2010-02-03

    Thiophosgene (Cl{sub 2}CS) is a favorite model system for studies of vibrational dynamics. But there are no previous rotationally-resolved infrared studies because the spectra are very congested due to its (relatively) large mass and multiple isotopic species. Here we report a detailed gas-phase study of the nu{sub 2} (approx504 cm{sup -1}) and nu{sub 4} (approx471 cm{sup -1}) fundamental bands, based on spectra obtained at the Canadian Light Source far-infrared beamline using synchrotron radiation and a Bruker IFS125 FT spectrometer.

  3. High-Resolution Infrared Spectroscopy with Synchrotron Sources

    SciTech Connect

    McKellar, A.

    2010-01-01

    Most applications of synchrotron radiation lie in the ultraviolet and X-ray region, but it also serves as a valuable continuum source of infrared (IR) light which is much brighter (i.e. more highly directional) than that from normal thermal sources. The synchrotron brightness advantage was originally exploited for high spatial resolution spectroscopy of condensed-phase samples. But it is also valuable for high spectral resolution of gas-phase samples, particularly in the difficult far-IR (terahertz) range (1/{lambda} {approx} 10-1000 cm{sup -1}). Essentially, the synchrotron replaces the usual thermal source in a Fourier transform IR spectrometer, giving a increase of up to two (or even more) orders of magnitude in signal at very high-resolution. Following up on pioneering work in Sweden (MAX-lab) and France (LURE), a number of new facilities have recently been constructed for high-resolution gas-phase IR spectroscopy. In the present paper, this new field is reviewed. The advantages and difficulties associated with synchrotron IR spectroscopy are outlined, current and new facilities are described, and past, present, and future spectroscopic results are summarized.

  4. High-Resolution Mars Camera Test Image of Moon (Infrared)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This crescent view of Earth's Moon in infrared wavelengths comes from a camera test by NASA's Mars Reconnaissance Orbiter spacecraft on its way to Mars. The mission's High Resolution Imaging Science Experiment camera took the image on Sept. 8, 2005, while at a distance of about 10 million kilometers (6 million miles) from the Moon. The dark feature on the right is Mare Crisium. From that distance, the Moon would appear as a star-like point of light to the unaided eye. The test verified the camera's focusing capability and provided an opportunity for calibration. The spacecraft's Context Camera and Optical Navigation Camera also performed as expected during the test.

    The Mars Reconnaissance Orbiter, launched on Aug. 12, 2005, is on course to reach Mars on March 10, 2006. After gradually adjusting the shape of its orbit for half a year, it will begin its primary science phase in November 2006. From the mission's planned science orbit about 300 kilometers (186 miles) above the surface of Mars, the high resolution camera will be able to discern features as small as one meter or yard across.

  5. The TIROS-N high resolution infrared radiation sounder

    NASA Technical Reports Server (NTRS)

    Koenig, E. W.

    1979-01-01

    The high-resolution infrared radiation sounder (HIRS/2) was developed and flown on the Television and Infrared Observation Satellite, N Series (TIROS-N) as one means of obtaining atmospheric vertical profile information. The HIRS/2 receives visible and infrared spectrum radiation through a single telescope and selects 20 narrow spectral channels by means of a rotating filter wheel. A passive radiant cooler provides an operating temperature of 106.7K for the HgCdTe and InSb detectors while the visible detector operates at instrument frame temperature. Low noise amplifiers and digital processing provide 13 bit data for spacecraft data multiplexing and transmission. The qualities of system performance that determine sounding capability are the dynamic range of data collection, the noise equivalent radiance of the system, the registration of the air columns sampled in each channel, and the ability to upgrade the calibration of the instrument to maintain the performance standard throughout life. The basic performance of the instrument in test is described. Early orbital information from the TIROS-N launched on October 13, 1978 are given and some observations on system quality are made.

  6. Design of the WIYN High Resolution Infrared Camera (WHIRC)

    NASA Astrophysics Data System (ADS)

    Smee, S. A.; Barkhouser, R. H.; Scharfstein, G. A.; Meixner, M.; Orndorff, J. D.; Miller, T.

    2011-01-01

    The WIYN High Resolution Infrared Camera (WHIRC) is a high-resolution near-infrared imager (0.8-2.5 μm) designed to produce superb images over a moderate (3.3' × 3.4') field of view on the WIYN 3.5 m telescope at Kitt Peak National Observatory. It takes scientific advantage of the excellent image quality produced by the telescope and its image stabilization subsystem, the WIYN Tip-Tilt Module (WTTM), which is located on one of two Nasmyth ports. WHIRC mounts to WTTM and reimages the WTTM focal plane to a plate scale of 0.1'' pixel-1 at the WHIRC detector. Its straight-through optical path makes for a compact, very low mass, instrument—a necessity, given the stringent moment-loading requirement at the WTTM interface. The WHIRC optical path consists of a vacuum window, a five-element collimator, a dual filter wheel, a five-element achromatic camera, and a 2k2 Raytheon VIRGO mercury cadmium telluride (HgCdTe) detector. A novel all-aluminum lens cell design is used to achieve 13 μm lens centering tolerances between ambient and the 77 K operating temperature. A suite of 13 filters facilitates broadband (J, H, and Ks) imaging, as well as narrowband imaging tailored to a variety of astronomical investigations. The imaging performance of WHIRC is excellent. Irrespective of seeing, the telescope, and WTTM, WHIRC delivers 0.13'', 0.11'', and 0.08'' FWHM images in J, H, and Ks, respectively. On sky, the imaging is equally impressive yielding images as good as ~0.25 FWHM in Ks. In this article we describe the WHIRC design in detail and present the predicted and measured instrument performance.

  7. A high-resolution Fourier-transform infrared spectrometer.

    NASA Technical Reports Server (NTRS)

    Johnson, H. L.; Forbes, F. F.; Thompson, R. I.; Steinmetz , D. L.; Harris, O.

    1973-01-01

    We have developed a Fourier-transform infrared spectrometer having a resolution of 0.5/cm over the range of wavelength from 1 to 5.5 microns. It has been used to observe the sun over this wavelength range from a Lear Jet flying at an altitude of 14 km, and to observe a number of stars from the ground, using the 229-cm telescope of the Steward Observatory and the 152-cm aluminum-mirror telescope at the Observatorio Astronomico Nacional in the Sierra de San Pedro Martir, Baja California, Mexico. The solar spectrum is given here, while the ground-based spectra are being published separately.

  8. Partial homogeneity based high-resolution nuclear magnetic resonance spectra under inhomogeneous magnetic fields

    SciTech Connect

    Wei, Zhiliang; Lin, Liangjie; Lin, Yanqin E-mail: chenz@xmu.edu.cn; Chen, Zhong E-mail: chenz@xmu.edu.cn; Chen, Youhe

    2014-09-29

    In nuclear magnetic resonance (NMR) technique, it is of great necessity and importance to obtain high-resolution spectra, especially under inhomogeneous magnetic fields. In this study, a method based on partial homogeneity is proposed for retrieving high-resolution one-dimensional NMR spectra under inhomogeneous fields. Signals from series of small voxels, which characterize high resolution due to small sizes, are recorded simultaneously. Then, an inhomogeneity correction algorithm is developed based on pattern recognition to correct the influence brought by field inhomogeneity automatically, thus yielding high-resolution information. Experiments on chemical solutions and fish spawn were carried out to demonstrate the performance of the proposed method. The proposed method serves as a single radiofrequency pulse high-resolution NMR spectroscopy under inhomogeneous fields and may provide an alternative of obtaining high-resolution spectra of in vivo living systems or chemical-reaction systems, where performances of conventional techniques are usually degenerated by field inhomogeneity.

  9. Automatic one dimensional spectra extraction for Weihai fiber-fed high resolution echelle spectra

    NASA Astrophysics Data System (ADS)

    Hu, Shao Ming; Gao, Dong Yang

    2014-11-01

    One fiber-fed high resolution echelle spectrograph was built for the one meter telescope atWeihai Observatory of Shandong University. It is used for exoplanet searching by radial velocity method and for stellar spectra analysis. One dimensional spectra extraction from the raw echelle data is researched in this paper. Flat field images with different exposure times were used to trace the order position accurately. The accurate background was fitted from each CCD image and it was subtracted from the raw image to correct the background and straylight. The intensity of each order decreases towards the order margin, and the lengths of order are different between the blue and red regions. The order tracing during the data reduction was investigated in this work. Accurate flux can be obtained after considering the effects of bad pixels, the curvature of each order and so on. One Interactive Data Language program for one dimensional spectra extraction was adopted and implemented to echelle data reduction for Weihai fiber-fed high resolution echelle spectra, and the results are illustrated here. The program is efficient and accurate for echelle data reduction. It can be adopted to reduce data taken by other instruments even the spectrographs in other fields, and it is very convenient for astronomers.

  10. LSD-based analysis of high-resolution stellar spectra

    NASA Astrophysics Data System (ADS)

    Tsymbal, V.; Tkachenko, A.; Van, Reeth T.

    2014-11-01

    We present a generalization of the method of least-squares deconvolution (LSD), a powerful tool for extracting high S/N average line profiles from stellar spectra. The generalization of the method is effected by extending it towards the multiprofile LSD and by introducing the possibility to correct the line strengths from the initial mask. We illustrate the new approach by two examples: (a) the detection of astroseismic signatures from low S/N spectra of single stars, and (b) disentangling spectra of multiple stellar objects. The analysis is applied to spectra obtained with 2-m class telescopes in the course of spectroscopic ground-based support for space missions such as CoRoT and Kepler. Usually, rather high S/N is required, so smaller telescopes can only compete successfully with more advanced ones when one can apply a technique that enables a remarkable increase in the S/N of the spectra which they observe. Since the LSD profiles have a potential for reconstruction what is common in all the spectral profiles, it should have a particular practical application to faint stars observed with 2-m class telescopes and whose spectra show remarkable LPVs.

  11. Stratospheric NO and NO2 profiles at sunset from analysis of high-resolution balloon-borne infrared solar absorption spectra obtained at 33 deg N and calculations with a time-dependent photochemical model

    SciTech Connect

    Rinsland, C.P.; Boughner, R.E.; Larsen, J.C.; Goldman, A.

    1984-08-01

    Simultaneous stratospheric vertical profiles of NO and NO2 at sunset were derived from an analysis of infrared solar absorption spectra recorded from a float altitude of 33 km with an interferometer system during a balloon flight. A nonlinear least squares procedure was used to analyze the spectral data in regions of absorption by NO and NO2 lines. Normalized factors, determined from calculations of time dependent altitude profiles with a detailed photochemical model, were included in the onion peeling analysis to correct for the rapid diurnal changes in NO and NO2 concentrations with time near sunset. The CO2 profile was also derived from the analysis and is reported.

  12. Stratospheric NO and NO2 profiles at sunset from analysis of high-resolution balloon-borne infrared solar absorption spectra obtained at 33 deg N and calculations with a time-dependent photochemical model

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Boughner, R. E.; Larsen, J. C.; Goldman, A.; Murcray, F. J.; Murcray, D. G.

    1984-01-01

    Simultaneous stratospheric vertical profiles of NO and NO2 at sunset were derived from an analysis of infrared solar absorption spectra recorded from a float altitude of 33 km with an interferometer system during a balloon flight. A nonlinear least squares procedure was used to analyze the spectral data in regions of absorption by NO and NO2 lines. Normalized factors, determined from calculations of time dependent altitude profiles with a detailed photochemical model, were included in the onion peeling analysis to correct for the rapid diurnal changes in NO and NO2 concentrations with time near sunset. The CO2 profile was also derived from the analysis and is reported.

  13. High-resolution microwave spectra of solar bursts

    NASA Technical Reports Server (NTRS)

    Stahli, M.; Gary, D. E.; Hurford, G. J.

    1989-01-01

    A phenomenological and statistical study of flares observed in total power with the frequency-agile interferometer at the Owens Valley Radio Observatory during several months of high solar activity in 1981 is reported. Roughly 80 percent of the events have a complex spectrum consisting of more than one spectral component, implying that the microwave radiation of a burst usually does not come from a single homogeneous source. The presence of more than one component can lead to significant errors when data with low spectral resolution are used to determine the low-side spectral index. The low-frequency slope of a single spectra component is often steeper than expected, and the peak frequency stays nearly constant throughout a microwave event.

  14. Water Vapor on Betelgeuse as Revealed by TEXES High-Resolution 12 μm Spectra

    NASA Astrophysics Data System (ADS)

    Ryde, N.; Harper, G. M.; Richter, M. J.; Greathouse, T. K.; Lacy, J. H.

    2006-02-01

    The outer atmosphere of the M supergiant Betelgeuse is puzzling. Published observations of different kinds have shed light on different aspects of the atmosphere, but no unified picture has emerged. They have shown, for example, evidence of a water envelope (MOLsphere) that in some studies is found to be optically thick in the mid-infrared. In this paper, we present high-resolution, mid-infrared spectra of Betelgeuse recorded with the TEXES spectrograph. The spectra clearly show absorption features of water vapor and OH. We show that a spectrum based on a spherical, hydrostatic model photosphere with Teff=3600 K, an effective temperature often assumed for Betelgeuse, fails to model the observed lines. Furthermore, we show that published MOLsphere scenarios are unable to explain our data. However, we are able to model the observed spectrum reasonably well by adopting a cooler outer photospheric structure corresponding to Tmod=3250 K. The success of this model may indicate that the observed mid-infrared lines are formed in cool photospheric surface regions. Given the uncertainties of the temperature structure and the likely presence of inhomogeneities, we cannot rule out the possibility that our spectrum could be mostly photospheric, albeit nonclassical. Our data put new, strong constraints on atmospheric models of Betelgeuse, and we conclude that continued investigation requires consideration of nonclassical model photospheres, as well as possible effects of a MOLsphere. We show that the mid-infrared water vapor features have great diagnostic value for the environments of K and M (super)giant star atmospheres.

  15. SPECTRA OF STRONG MAGNETOHYDRODYNAMIC TURBULENCE FROM HIGH-RESOLUTION SIMULATIONS

    SciTech Connect

    Beresnyak, Andrey

    2014-04-01

    Magnetohydrodynamic (MHD) turbulence is present in a variety of solar and astrophysical environments. Solar wind fluctuations with frequencies lower than 0.1 Hz are believed to be mostly governed by Alfvénic turbulence with particle transport depending on the power spectrum and the anisotropy of such turbulence. Recently, conflicting spectral slopes for the inertial range of MHD turbulence have been reported by different groups. Spectral shapes from earlier simulations showed that MHD turbulence is less scale-local compared with hydrodynamic turbulence. This is why higher-resolution simulations, and careful and rigorous numerical analysis is especially needed for the MHD case. In this Letter, we present two groups of simulations with resolution up to 4096{sup 3}, which are numerically well-resolved and have been analyzed with an exact and well-tested method of scaling study. Our results from both simulation groups indicate that the asymptotic power spectral slope for all energy-related quantities, such as total energy and residual energy, is around –1.7, close to Kolmogorov's –5/3. This suggests that residual energy is a constant fraction of the total energy and that in the asymptotic regime of Alfvénic turbulence magnetic and kinetic spectra have the same scaling. The –1.5 slope for energy and the –2 slope for residual energy, which have been suggested earlier, are incompatible with our numerics.

  16. Spectra of Strong Magnetohydrodynamic Turbulence from High-resolution Simulations

    NASA Astrophysics Data System (ADS)

    Beresnyak, Andrey

    2014-04-01

    Magnetohydrodynamic (MHD) turbulence is present in a variety of solar and astrophysical environments. Solar wind fluctuations with frequencies lower than 0.1 Hz are believed to be mostly governed by Alfvénic turbulence with particle transport depending on the power spectrum and the anisotropy of such turbulence. Recently, conflicting spectral slopes for the inertial range of MHD turbulence have been reported by different groups. Spectral shapes from earlier simulations showed that MHD turbulence is less scale-local compared with hydrodynamic turbulence. This is why higher-resolution simulations, and careful and rigorous numerical analysis is especially needed for the MHD case. In this Letter, we present two groups of simulations with resolution up to 40963, which are numerically well-resolved and have been analyzed with an exact and well-tested method of scaling study. Our results from both simulation groups indicate that the asymptotic power spectral slope for all energy-related quantities, such as total energy and residual energy, is around -1.7, close to Kolmogorov's -5/3. This suggests that residual energy is a constant fraction of the total energy and that in the asymptotic regime of Alfvénic turbulence magnetic and kinetic spectra have the same scaling. The -1.5 slope for energy and the -2 slope for residual energy, which have been suggested earlier, are incompatible with our numerics.

  17. Long-Term Trends in the Concentrations of SF6, CHClF2, and COF2 in the Lower Stratosphere from Analysis of High-Resolution Infrared Solar Occultation Spectra

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Goldman, A.; Murcray, F. J.; Blatherwick, R. D.; Kosters, J. J.; Murcray, D. G.; Sze, N. D.; Massie, S. T.

    1990-01-01

    Long-term trends in the concentrations of SF6, CHClF2 (CFC-22), and COF2 in the lower stratosphere have been derived from analysis of ca. 1980 and more recent infrared solar occultation spectra recorded near 32 deg N latitude at approx. 0.02/ cm resolution. Consistent sets of line parameters and spectral calibration methods have been used in the retrievals to minimize systematic error effects. Quoted error limits are 1 sigma estimated precisions. The SF6 and CHClF2 results are based on spectra recorded by balloon-borne interferometers in March 1981 and June 1988 and a comparison of these results with the Atmospheric Trace Molecule Spectroscopy (ATMOS) Experiment/Spacelab 3 measurements obtained in May 1985 near 30 deg N latitude. In the 13-18 km altitude range the mean measured SF6 mixing ratio in parts per trillion by volume (pptv) increased from 1.17 +/- 0.21 in March 1981 to 2.02 +/- 0.20 pptv in June 1988, and the CHClF2 mixing ratio below 15 km altitude increased from 51 +/- 8 pptv in March 1981 to 102 +/- 10 pptv in June 1988. The CHClF2 retrievals used new empirical CHClF2 line parameters derived from 0.03/cm resolution laboratory spectra recorded at six temperatures between 203 and 293 K; the derived mixing ratios are approx. 30% higher than obtained with earlier sets of line parameters, thereby removing a large discrepancy noted previously between IR and in situ measurements of CHClF2. Assuming an exponential growth model for fitting the trends, SF6 and CHClF2 mean increase rates of 7.4% +/- 1.9% and 9.4% +/- 1.3% /year, are obtained, respectively, which correspond to cumulative increases by factors of approx. 1.7 and -2.0 in the concentrations of these gases over the 7.2-year measurement period. Analysis of spectra recorded in October 1979 and April 1989 yields COF2 volume mixing ratios that are respectively 0.44 +/- 0.17 and 1.21 +/- 0.24 times the ATMOS/Spacelab 3 values, from which an average COF2 increase rate of 10.3 +/- 1.8%/ year over this time

  18. A high-resolution atlas of the infrared spectrum of the Sun and the Earth atmosphere from space: A compilation of ATMOS spectra of the region from 650 to 4800 cm (2.3 to 16 micron). Volume 1: The Sun

    NASA Technical Reports Server (NTRS)

    Farmer, Crofton B.; Norton, Robert H.

    1989-01-01

    During the period April 29 through May 2, 1985, the Atmospheric Trace Molecular Spectroscopy experiment was operated as part of the Spacelab-3 payload of the shuttle Challenger. The instrument, a modified Michelson Interferometer covering the frequency range from 600 to 5000/cm, at a spectral resolution of 0.01/cm, recorded infrared spectra of the Sun and of the Earth's atmosphere at times close to entry into and exit from occultation by the Earth's limb as seen from the shuttle orbit of 360 km. Spectra were obtained that are free from absorptions due to constituents of the atmosphere (i.e., solar pure spectra), as well as spectra of the atmosphere itself, covering line-of-sight tangent altitudes that span the range from the lower thermosphere to the bottom of the troposphere. This atlas, believed to be the first record of observations of the continuous high resolution infrared spectrum of the Sun and the Earth's atmosphere from space, provides a compilation of these spectra arranged in a hardcopy format suitable for quick-look reference purposes; the data are also available in digital form.

  19. A high-resolution atlas of the infrared spectrum of the Sun and the Earth atmosphere from space: A compilation of ATMOS spectra of the region from 650 to 4800 cm (2.3 to 16 micron). Volume 1: The Sun

    NASA Astrophysics Data System (ADS)

    Farmer, Crofton B.; Norton, Robert H.

    During the period April 29 through May 2, 1985, the Atmospheric Trace Molecular Spectroscopy experiment was operated as part of the Spacelab-3 payload of the shuttle Challenger. The instrument, a modified Michelson Interferometer covering the frequency range from 600 to 5000/cm, at a spectral resolution of 0.01/cm, recorded infrared spectra of the Sun and of the Earth's atmosphere at times close to entry into and exit from occultation by the Earth's limb as seen from the shuttle orbit of 360 km. Spectra were obtained that are free from absorptions due to constituents of the atmosphere (i.e., solar pure spectra), as well as spectra of the atmosphere itself, covering line-of-sight tangent altitudes that span the range from the lower thermosphere to the bottom of the troposphere. This atlas, believed to be the first record of observations of the continuous high resolution infrared spectrum of the Sun and the Earth's atmosphere from space, provides a compilation of these spectra arranged in a hardcopy format suitable for quick-look reference purposes; the data are also available in digital form.

  20. VizieR Online Data Catalog: High-resolution NIR spectra of local giants (Feuillet+, 2016)

    NASA Astrophysics Data System (ADS)

    Feuillet, D. K.; Bovy, J.; Holtzman, J.; Girardi, L.; MacDonald, N.; Majewski, S. R.; Nidever, D. L.

    2016-04-01

    We present a sample of 705 local giant stars observed using the New Mexico State University 1m telescope with the Sloan Digital Sky Survey-III/Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectrograph, for which we estimate stellar ages and the local star formation history (SFH). The high-resolution (R~22500), near infrared (1.51-1.7μm) APOGEE spectra provide measurements of stellar atmospheric parameters (temperature, surface gravity, [M/H], and [α/M]). Due to the smaller uncertainties in surface gravity possible with high-resolution spectra and accurate Hipparcos distance measurements, we are able to calculate the stellar masses to within 30%. For giants, the relatively rapid evolution up the red giant branch allows the age to be constrained by the mass. We examine methods of estimating age using both the mass-age relation directly and a Bayesian isochrone matching of measured parameters, assuming a constant SFH. To improve the SFH prior, we use a hierarchical modeling approach to constrain the parameters of the model SFH using the age probability distribution functions of the data. The results of an α-dependent Gaussian SFH model show a clear age-[α/M] relation at all ages. Using this SFH model as the prior for an empirical Bayesian analysis, we determine ages for individual stars. The resulting age-metallicity relation is flat, with a slight decrease in [M/H] at the oldest ages and a ~0.5 dex spread in metallicity across most ages. For stars with ages <~1Gyr we find a smaller spread, consistent with radial migration having a smaller effect on these young stars than on the older stars. (1 data file).

  1. Criteria for spectral classification of cool stars using high-resolution spectra

    NASA Astrophysics Data System (ADS)

    Montes, David; Martínez-Arnáiz, Raquel M.; Maldonado, Jesus; Roa-Llamazares, Juan; López-Santiago, Javier; Crespo-Chacón, Inés; Solano, Enrique

    2007-08-01

    We have compiled a large number of optical spectra of cool stars taken with different high-resolution echelle spectrographs (R 40 000). Many of those are available as spectral libraries (Montes et al. 1997, 1998, 1999, spectra.html)>.

  2. Water in the deep atmosphere of Venus from high-resolution spectra of the night side

    NASA Technical Reports Server (NTRS)

    De Bergh, C.; Bezard, B.; Crisp, D.; Maillard, J. P.; Owen, T.; Pollack, J.; Grinspoon, D.

    1995-01-01

    High-resolution, near-infrared (1.09 to 2.5 micrometers) spectra of the night side of Venus have been obtained in 1990 and 1991 using the Fourier Transform Spectrometer at the 3.6-m Canada-France-Hawaii telescope. Absorptions due to H2O were detected in spectral windows near 2.3, 1.74, and 1.18 micrometers. Our analysis of these absorptions constrains the abundance of water vapor in three different altitude ranges located between the clouds and the surface: 30-40 km, 15-25 km and 0-15 km. A constant water vapor mixing ratio of 30 +/- 15 ppm below the clouds can fit the observations. These values are consistent with recent near-infrared studies of the night side of Venus at lower spectral resolution. The atmosphere of Venus appears to be dryer than originally suggested by the in-situ measurements made by the Pioneer Venus and Venera mass-spectrometers and gas-chromatographs.

  3. Synthesis, High-Resolution Infrared Spectroscopy, and Vibrational Structure of Cubane, C8H8.

    PubMed

    Boudon, V; Lamy, M; Dugue-Boyé, F; Pirali, O; Gruet, S; D'Accolti, L; Fusco, C; Annese, C; Alikhani, M E

    2016-06-30

    Carbon-cage molecules have generated a considerable interest from both experimental and theoretical points of view. We recently performed a high-resolution study of adamantane (C10H16), the smallest hydrocarbon cage belonging to the diamandoid family ( Pirali , O. ; et al. J. Chem. Phys. 2012 , 136 , 024310 ). There exist another family of hydrocarbon cages with additional interesting chemical properties: the so-called platonic hydrocarbons that comprise dodecahedrane (C20H20) and cubane (C8H8). Both possess C-C bond angles that deviate from the tetrahedral angle (109.8°) of the sp(3) hybridized form of carbon. This generates a considerable strain in the molecule. We report a new wide-range high-resolution study of the infrared spectrum of cubane. The sample was synthesized in Bari upon decarboxylation of 1,4-cubanedicarboxylic acid thanks to the improved synthesis of literature. Several spectra have been recorded at the AILES beamline of the SOLEIL synchrotron facility. They cover the 600-3200 cm(-1) region. Besides the three infrared-active fundamentals (ν10, ν11, and ν12), we could record many combination bands, all of them displaying a well-resolved octahedral rotational structure. We present here a preliminary analysis of some of the recorded bands, performed thanks the SPVIEW and XTDS software, based on the tensorial formalism developed in the Dijon group. A comparison with ab initio calculations, allowing to identify some combination bands, is also presented. PMID:27267150

  4. Time series of high-resolution spectra of SN 2014J observed with the TIGRE telescope

    NASA Astrophysics Data System (ADS)

    Jack, D.; Mittag, M.; Schröder, K.-P.; Schmitt, J. H. M. M.; Hempelmann, A.; González-Pérez, J. N.; Trinidad, M. A.; Rauw, G.; Cabrera Sixto, J. M.

    2015-08-01

    We present a time series of high-resolution spectra of the Type Ia supernova 2014J, which exploded in the nearby galaxy M82. The spectra were obtained with the HEROS échelle spectrograph installed at the 1.2-m TIGRE telescope. We present a series of 33 spectra with a resolution of R ≈ 20 000, which covers the important bright phases in the evolution of SN 2014J during the period from 2014 January 24 to April 1. The spectral evolution of SN 2014J is derived empirically. The expansion velocities of the Si II P-Cygni features were measured and show the expected decreasing behaviour, beginning with a high velocity of 14 000 km s-1 on January 24. The Ca II infrared triplet feature shows a high-velocity component with expansion velocities of >20 000 km s-1 during the early evolution apart from the normal component showing similar velocities as Si II. Further broad P-Cygni profiles are exhibited by the principal lines of Ca II, Mg II and Fe II. The TIGRE SN 2014J spectra also resolve several very sharp Na I D doublet absorption components. Our analysis suggests interesting substructures in the interstellar medium of the host galaxy M82, as well as in our Milky Way, confirming other work on this SN. We were able to identify the interstellar absorption of M82 in the lines of Ca II H & K at 3933 and 3968 Å as well as K I at 7664 and 7698 Å. Furthermore, we confirm several diffuse interstellar bands, at wavelengths of 6196, 6283, 6376, 6379and 6613 Å and give their measured equivalent widths.

  5. High-Resolution Vibrational Spectra of Furazan III. The A1 Fundamentals v3 at ~ 1316 cm-1 and v4 at ~ 1036 cm-1 from Fourier-Transform Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Stiefvater, Otto L.

    1993-04-01

    With prior information on vibrationally excited states from DRM microwave spectroscopy, two B-type high-resolution FT-IR bands of furazan were examined to yield the band origins v03 = 1316.2254 cm-1 and v04 = 1036.1689 cm-1 with an estimated absolute uncertainty of ±0.0001 cm-1 . The rotational and distortion constants of both fundamental states were refined by the combination of rotational with rovibrational data in the least-squares fits of the bands.

  6. Line broadening interference for high-resolution nuclear magnetic resonance spectra under inhomogeneous magnetic fields

    SciTech Connect

    Wei, Zhiliang; Yang, Jian; Lin, Yanqin E-mail: chenz@xmu.edu.cn; Chen, Zhong E-mail: chenz@xmu.edu.cn; Chen, Youhe

    2015-04-07

    Nuclear magnetic resonance spectroscopy serves as an important tool for analyzing chemicals and biological metabolites. However, its performance is subject to the magnetic-field homogeneity. Under inhomogeneous fields, peaks are broadened to overlap each other, introducing difficulties for assignments. Here, we propose a method termed as line broadening interference (LBI) to provide high-resolution information under inhomogeneous magnetic fields by employing certain gradients in the indirect dimension to interfere the magnetic-field inhomogeneity. The conventional spectral-line broadening is thus interfered to be non-diagonal, avoiding the overlapping among adjacent resonances. Furthermore, an inhomogeneity correction algorithm is developed based on pattern recognition to recover the high-resolution information from LBI spectra. Theoretical deductions are performed to offer systematic and detailed analyses on the proposed method. Moreover, experiments are conducted to prove the feasibility of the proposed method for yielding high-resolution spectra in inhomogeneous magnetic fields.

  7. High-Resolution Infrared and Electron-Diffraction Studies of Trimethylenecyclopropane ([3]-Radialene)

    SciTech Connect

    Wright, Corey; Holmes, Joshua; Nibler, Joseph W.; Hedberg, Kenneth; White, James D.; Hedberg, Lise; Weber, Alfons; Blake, Thomas A.

    2013-05-16

    Combined high-resolution spectroscopic, electron-diffraction, and quantum theoretical methods are particularly advantageous for small molecules of high symmetry and can yield accurate structures that reveal subtle effects of electron delocalization on molecular bonds. The smallest of the radialene compounds, trimethylenecyclopropane, [3]-radialene, has been synthesized and examined in the gas phase by these methods. The first high-resolution infrared spectra have been obtained for this molecule of D3h symmetry, leading to an accurate B0 rotational constant value of 0.1378629(8) cm-1, within 0.5% of the value obtained from electronic structure calculations (density functional theory (DFT) B3LYP/cc-pVTZ). This result is employed in an analysis of electron-diffraction data to obtain the rz bond lengths (in Å): C-H = 1.072 (17), C-C = 1.437 (4), and C=C = 1.330 (4). The analysis does not lead to an accurate value of the HCH angle; however, from comparisons of theoretical and experimental angles for similar compounds, the theoretical prediction of 117.5° is believed to be reliable to within 2°. The effect of electron delocalization in radialene is to reduce the single C-C bond length by 0.07 Å compared to that in cyclopropane.

  8. Chemical abundances of 11 bulge stars from high-resolution, near-IR spectra

    NASA Astrophysics Data System (ADS)

    Ryde, N.; Gustafsson, B.; Edvardsson, B.; Meléndez, J.; Alves-Brito, A.; Asplund, M.; Barbuy, B.; Hill, V.; Käufl, H. U.; Minniti, D.; Ortolani, S.; Renzini, A.; Zoccali, M.

    2010-01-01

    Context. It is debated whether the Milky Way bulge has characteristics more similar to those of a classical bulge than those of a pseudobulge. Detailed abundance studies of bulge stars are important when investigating the origin, history, and classification of the bulge. These studies provide constraints on the star-formation history, initial mass function, and differences between stellar populations. Not many similar studies have been completed because of the large distance and high variable visual extinction along the line-of-sight towards the bulge. Therefore, near-IR investigations can provide superior results. Aims: To investigate the origin of the bulge and study its chemical abundances determined from near-IR spectra for bulge giants that have already been investigated with optical spectra. The optical spectra also provide the stellar parameters that are very important to the present study. In particular, the important CNO elements are determined more accurately in the near-IR. Oxygen and other α elements are important for investigating the star-formation history. The C and N abundances are important for determining the evolutionary stage of the giants and the origin of C in the bulge. Methods: High-resolution, near-infrared spectra in the H band were recorded using the CRIRES spectrometer mounted on the Very Large Telescope. The CNO abundances are determined from the numerous molecular lines in the wavelength range observed. Abundances of the α elements Si, S, and Ti are also determined from the near-IR spectra. Results: The abundance ratios [O/Fe], [Si/Fe], and [S/Fe] are enhanced to metallicities of at least [Fe/H] = -0.3, after which they decline. This suggests that the Milky Way bulge experienced a rapid and early burst of star formation similar to that of a classical bulge. However, a similarity between the bulge trend and the trend of the local thick disk seems to be present. This similarity suggests that the bulge could have had a pseudobulge

  9. High resolution spectral analysis of oxygen. II. Rotational spectra of a(1)Δ(g)  O2 isotopologues.

    PubMed

    Drouin, Brian J; Gupta, Harshal; Yu, Shanshan; Miller, Charles E; Müller, Holger S P

    2012-07-14

    As part of a comprehensive review on molecular oxygen spectroscopy, we have measured rotational spectra of isotopic forms of molecular oxygen in its a(1)Δ(g) electronic state with high-resolution terahertz spectroscopy. The data are recorded in close proximity to predicted positions. Due to the high resolution and good signal-to-noise ratio, the fundamental hyperfine parameters eQq and C(I) are determinable for (17)O-substituted species for the first time. A refined nuclear spin orbit coupling constant, a = -211.9328(283) MHz, was determined, and is roughly two orders of magnitude more precise than values determined from near infrared spectroscopy or electron spin resonance studies. Vibrationally excited oxygen in the a(1)Δ(g) electronic state was also observable with small signal levels for many of the rotational transitions. PMID:22803534

  10. Intercomparison of three microwave/infrared high resolution line-by-line radiative transfer codes

    NASA Astrophysics Data System (ADS)

    Schreier, F.; Garcia, S. Gimeno; Milz, M.; Kottayil, A.; Höpfner, M.; von Clarmann, T.; Stiller, G.

    2013-05-01

    An intercomparison of three line-by-line (lbl) codes developed independently for atmospheric sounding - ARTS, GARLIC, and KOPRA - has been performed for a thermal infrared nadir sounding application assuming a HIRS-like (High resolution Infrared Radiation Sounder) setup. Radiances for the HIRS infrared channels and a set of 42 atmospheric profiles from the "Garand dataset" have been computed. Results of this intercomparison and a discussion of reasons of the observed differences are presented.

  11. Long-term trends in the concentrations of SF6, CHClF2, and COF2 in the lower stratosphere from analysis of high-resolution infrared solar occultation spectra

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Goldman, A.; Murcray, F. J.; Blatherwick, R. D.; Kosters, J. J.

    1990-01-01

    Long-term trends in the concentrations of SF6, CHClF2 in the lower stratosphere are derived using results from analyses of the 1980 and of several more recently obtained IR solar occultation spectra. Results show that the increase rates of SF6 and CHClF2 were about 7.4/yr and 9.4/yr, respectively, which correspond to cumulative increases by factors of about 1.7 and 2.0 in the concentrations of these gases over the 7.2 yr measurement period. The average increase rate for COF2 was 10.3/yr over the same time period. The present results are compared with previously reported observations and trends and with one-dimensional model calculations.

  12. High-Resolution Infrared Spectroscopy of Cubane, C_8H_8

    NASA Astrophysics Data System (ADS)

    Boudon, Vincent; Pirali, Olivier; Gruet, Sébastien; D'accolti, Lucia; Fusco, Caterina; Annese, Cosimo

    2014-06-01

    Carbon-cage molecules have generated a considerable interest from both experimental and theoretical point of views. We recently performed a high-resolution study of adamantane (C10H16), the smallest hydrocarbon cage belonging to the diamandoid family. There exist another family of hydrocarbon cages with additional interesting chemical properties: the so-called Platonic hydrocarbons that comprise dodecahedrane (C20H20) and cubane (C_8H_8). Both possess C-C bond angles that deviate from the tetrahedral angle (109.8°) of the sp^3 hybridized form of carbon. This generates a considerable strain in the molecule. Cubane itself has the highest density of all hydrocarbons (1.29 g/cm^3). This makes it able to store larges amounts of energy, although the molecule is fully stable. Up to now, only one high-resolution study of cubane has been performed on a few bands [2]. We report here a new wide-range high-resolution study of the infrared spectrum of cubane. The sample was synthesized in Bari upon decarboxylation of 1,4-cubanedicarboxylic acid thanks to the improved synthesis of literature [3]; its {}1H and 13C NMR, FTIR, and mass spectrometry agreed with reported data [4]. Several spectra have been recorded at the AILES beamline of the SOLEIL French synchrotron facility. They cover the 800 to 3100 cm-1 region. Besides the three infrared-active fundamentals (ν10, ν11 and ν12), we could record many combination bands, all of them displaying a well-resolved octahedral rotational structure. We present here a preliminary analysis of some of the recorded bands, performed thanks the SPVIEW and XTDS software, based on the tensrorial formalism developed in the Dijon group [5]. [1] O. Pirali, V. Boudon, J. Oomens, M. Vervloet, J. Chem. Phys., 136, 024310 (2012). [2] A. S. Pine, A. G. Maki, A. G. Robiette, B. J. Krohn, J. K. G. Watson, Th. Urbanek, J. Am. Chem. Soc., 106, 891-897 (1984). [3] P. E. Eaton, N. Nordari, J. Tsanaktsidis, P. S. Upadhyaya, Synthesis, 1, 501, (1995). [4] E

  13. Millimeter-Wave and High-Resolution Infrared Spectra of Monoisotopic SC 80Se: Equilibrium, Ground State, and ν 1, mν 2, and nν 3 Rovibrational Parameters

    NASA Astrophysics Data System (ADS)

    Burger, H.; Demaison, J.; Drean, P.; Litz, M.; Willner, H.

    1995-04-01

    The Fourier transform infrared spectrum of monoisotopic SC80Se has been investigated in the ν2, ν3, 2ν2, 2ν3, and ν1 regions with a resolution between 3 and 4 × 10-3 cm-1. In addition, the millimeter-wave spectrum has been studied in the region 150 to 320 GHz, and ground and ν2 = 1 excited state transitions have been measured. Ground state constants, B0 = 2043.285 4(4) MHz and D0 = 146.53(5) Hz, have been determined from a merge of millimeter-wave data and ground state combination differences spanning J values up to 77 and 143, respectively. The band centers ν2 = 352.341 075(9) cm-1 and ν3 = 505.480 06(5)cm-1 have been determined. The rovibrational parameters of numerous overtone and combination levels (ν1νl22ν3) = 0200, 0220, 0310, 0330, 0400, 0420, 0002, and 0003 have been obtained from polynomial analyses whose standard deviations ranged from 0.7 to 3.5 × 10-4 cm-1. The 1000 level, νeff 1435.840 cm-1, is anharmonically perturbed by the 0400 level, with an avoided crossing at J = 55, and W12222 = 0.963 09(1) cm-1. Transitions to both the upper (E+) and lower (E-) sublevels of the dyad were observed for 1 ≤ J‧ ≤ 117 and 4 ≤ J‧ ≤ 171, respectively, and the deperturbed wavenumbers ν1 = 1435.542 76(2) and 4ν02 = 1432.725 00(3) cm-1 were derived. Furthermore, a local crossing of the E- and 0420 levels involving l-type resonance was observed at J = 91.

  14. Physical Properties of Young Brown Dwarfs and Very Low Mass Stars Inferred from High-resolution Model Spectra

    NASA Astrophysics Data System (ADS)

    Rice, Emily L.; Barman, T.; Mclean, Ian S.; Prato, L.; Kirkpatrick, J. Davy

    2010-01-01

    By comparing near-infrared spectra with atmospheric models, we infer the effective temperature, surface gravity, projected rotational velocity, and radial velocity for 21 very low mass stars and brown dwarfs. The unique sample consists of two sequences in spectral type from M6-M9, one of 5-10 Myr objects and one of >1 Gyr field objects. A third sequence is comprised of only ~M6 objects with ages ranging from <1 Myr to >1 Gyr. Spectra were obtained in the J band at medium (R ~ 2000) and high (R ~ 20,000) resolutions with NIRSPEC on the Keck II telescope. Synthetic spectra were generated from atmospheric structures calculated with the PHOENIX model atmosphere code. Using multi-dimensional least-squares fitting and Monte Carlo routines we determine the best-fit model parameters for each observed spectrum and note which spectral regions provide consistent results. We identify successes in the reproduction of observed features by atmospheric models, including pressure-broadened K I lines, and investigate deficiencies in the models, particularly missing FeH opacity, that will need to be addressed in order to extend our analysis to cooler objects. The precision that can be obtained for each parameter using medium- and high-resolution near-infrared spectra is estimated and the implications for future studies of very low mass stars and brown dwarfs are discussed.

  15. The Fundamental Quadrupole Band of (14)N2: Line Positions from High-Resolution Stratospheric Solar Absorption Spectra

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Zander, R.; Goldman, A.; Murcray, F. J.; Murcray, D. G.; Grunson, M. R.; Farmer, C. B.

    1991-01-01

    The purpose of this note is to report accurate measurements of the positions of O- and S-branch lines of the (1-0) vibration-rotation quadrupole band of molecular nitrogen ((14)N2) and improved Dunham coefficients derived from a simultaneous least-squares analysis of these measurements and selected infrared and far infrared data taken from the literature. The new measurements have been derived from stratospheric solar occultation spectra recorded with Fourier transform spectrometer (FTS) instruments operated at unapodized spectral resolutions of 0.002 and 0.01 /cm. The motivation for the present investigation is the need for improved N2 line parameters for use in IR atmospheric remote sensing investigations. The S branch of the N2 (1-0) quadrupole band is ideal for calibrating the line-of-sight airmasses of atmospheric spectra since the strongest lines are well placed in an atmospheric window, their absorption is relatively insensitive to temperature and is moderately strong (typical line center depths of 10 to 50% in high-resolution ground-based solar spectra and in lower stratospheric solar occultation spectra), and the volume mixing ratio of nitrogen is constant in the atmosphere and well known. However, a recent investigation has'shown the need to improve the accuracies of the N2 fine positions, intensities, air-broadened half-widths, and their temperature dependences to fully exploit this calibration capability (1). The present investigation addresses the problem of improving the accuracy of the N2 line positions.

  16. High Resolution Infrared Radiation Sounder (HIRS) for the Nimbus F Spacecraft

    NASA Technical Reports Server (NTRS)

    Koenig, E. W.

    1975-01-01

    Flown on Nimbus F in June 1975, the high resolution infrared radiation sounder (HIRS) scans with a geographical resolution of 23KM and samples radiance in seventeen selected spectral channels from visible (.7 micron) to far IR (15 micron). Vertical temperature profiles and atmospheric moisture content can be inferred from the output. System operation and test results are described.

  17. High-resolution photoelectron spectra of the pyrimidine-type nucleobases

    SciTech Connect

    Fulfer, K. D.; Hardy, D.; Poliakoff, E. D.; Aguilar, A. A.

    2015-06-14

    High-resolution photoelectron spectra of the gas phase pyrimidine-type nucleobases, thymine, uracil, and cytosine, were collected using synchrotron radiation over the photon energy range 17 ≤ hν ≤ 150 eV. These data provide the highest resolution photoelectron spectra of thymine, uracil, and cytosine published to date. By comparing integrated regions of the energy dependent photoelectron spectra of thymine, the ionization potentials of the first four ionic states of thymine were estimated to be 8.8, 9.8, 10.3, and 10.8 eV. The thymine data also show evidence for low energy shape resonances in three of the outermost valence electronic states. Comparing the uracil spectrum with the thymine spectrum, the four outermost valence electronic states of uracil likely begin at binding energies 9.3, 9.9, 10.5, and 11.0 eV. High-resolution spectra indicate only one tautomeric form of cytosine contributes significantly to the spectrum with the four outermost valence electronic states beginning at binding energies 8.9, 9.9, 10.4, and 10.85 eV.

  18. Genetic algorithm-based feature selection in high-resolution NMR spectra

    PubMed Central

    Cho, Hyun-Woo; Jeong, Myong K.; Park, Youngja; Ziegler, Thomas R.; Jones, Dean P.

    2011-01-01

    High-resolution nuclear magnetic resonance (NMR) spectroscopy has provided a new means for detection and recognition of metabolic changes in biological systems in response to pathophysiological stimuli and to the intake of toxins or nutrition. To identify meaningful patterns from NMR spectra, various statistical pattern recognition methods have been applied to reduce their complexity and uncover implicit metabolic patterns. In this paper, we present a genetic algorithm (GA)-based feature selection method to determine major metabolite features to play a significant role in discrimination of samples among different conditions in high-resolution NMR spectra. In addition, an orthogonal signal filter was employed as a preprocessor of NMR spectra in order to remove any unwanted variation of the data that is unrelated to the discrimination of different conditions. The results of k-nearest neighbors and the partial least squares discriminant analysis of the experimental NMR spectra from human plasma showed the potential advantage of the features obtained from GA-based feature selection combined with an orthogonal signal filter. PMID:21472035

  19. kspectrum: an open-source code for high-resolution molecular absorption spectra production

    NASA Astrophysics Data System (ADS)

    Eymet, V.; Coustet, C.; Piaud, B.

    2016-01-01

    We present the kspectrum, scientific code that produces high-resolution synthetic absorption spectra from public molecular transition parameters databases. This code was originally required by the atmospheric and astrophysics communities, and its evolution is now driven by new scientific projects among the user community. Since it was designed without any optimization that would be specific to any particular application field, its use could also be extended to other domains. kspectrum produces spectral data that can subsequently be used either for high-resolution radiative transfer simulations, or for producing statistic spectral model parameters using additional tools. This is a open project that aims at providing an up-to-date tool that takes advantage of modern computational hardware and recent parallelization libraries. It is currently provided by Méso-Star (http://www.meso-star.com) under the CeCILL license, and benefits from regular updates and improvements.

  20. High-resolution 6450-24500 A spectra of eta Carinae

    NASA Technical Reports Server (NTRS)

    Hamann, Fred; Depoy, D. L.; Johansson, Sveneric; Elias, Jay

    1994-01-01

    We discuss high-resolution (Delta lambda/lambda approximately equals 3000-8600) spectra of the central knot or 'star' in eta Car between approximately 6450 and approximately 24,500 A, and of the Homunculus approximately 7 sec southeast of the knot between approximately 6450 and approximately 9250 A. A complete flux calibrated list of more than 170 emission lines is provided longward of approximately 8780 A, with additional measurements of the strongest forbidden lines and Fe II features down to approximately 6700 A. The continuum flux increased by a factor of approximately 1.6 to approximately 2.0 at 23,000 A compared to recent measurements, by remained the same at approximately 11,000 A. This brightening and reddening of the IR continuum was accompanied by stronger H I and He I lines, constant or slightly weaker Fe II and (Fe II) lines, and increased extinction to A(sub V) approximately 5 mag to 6 mag (from A(sub V) approximately less than 3.2 mag previously). The complex line profiles fall into two categories: (1) broad emission and sometimes blueshifted absorptions that form in a high-velocity wind reaching at least 700 km/s and (2) narrow emission cores that may be associated with a low-velocity (equatorial?) wind with speeds approximately less than 100 km/s. The broad lines in the Homunculus have profiles and equivalent widths similar to the broad components in the know, but they are redshifted by approximately greater than 250 km/s due to rapid expansion of the reflecting dust. The reflected light spectrum of the Homunculus offers a better 'view' of the high-velocity wind because it is free of the many strong narrow lines in the knot. The range of excitation in both the high- and low-velocity regions encompasses He I recombination and Fe II emission, but excludes the lower ionization required for Fe I, the CO band heads, and the infrared Ca II triplet, which are not detected. The narrow forbidden lines indicate densities in excess of the critical densities

  1. Understanding AGB evolution in Galactic bulge stars from high-resolution infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Uttenthaler, S.; Blommaert, J. A. D. L.; Wood, P. R.; Lebzelter, T.; Aringer, B.; Schultheis, M.; Ryde, N.

    2015-08-01

    An analysis of high-resolution near-infrared spectra of a sample of 45 asymptotic giant branch (AGB) stars towards the Galactic bulge is presented. The sample consists of two subsamples, a larger one in the inner and intermediate bulge, and a smaller one in the outer bulge. The data are analysed with the help of hydrostatic model atmospheres and spectral synthesis. We derive the radial velocity of all stars, and the atmospheric chemical mix ([Fe/H], C/O, 12C/13C, Al, Si, Ti, and Y) where possible. Our ability to model the spectra is mainly limited by the (in)completeness of atomic and molecular line lists, at least for temperatures down to Teff ≈ 3100 K. We find that the subsample in the inner and intermediate bulge is quite homogeneous, with a slightly subsolar mean metallicity and only few stars with supersolar metallicity, in agreement with previous studies of non-variable M-type giants in the bulge. All sample stars are oxygen-rich, C/O < 1.0. The C/O and carbon isotopic ratios suggest that third dredge-up (3DUP) is absent among the sample stars, except for two stars in the outer bulge that are known to contain technetium. These stars are also more metal-poor than the stars in the intermediate or inner bulge. Current stellar masses are determined from linear pulsation models. The masses, metallicities and 3DUP behaviour are compared to AGB evolutionary models. We conclude that these models are partly in conflict with our observations. Furthermore, we conclude that the stars in the inner and intermediate bulge belong to a more metal-rich population that follows bar-like kinematics, whereas the stars in the outer bulge belong to the metal-poor, spheroidal bulge population.

  2. High-resolution Infrared Spectroscopy of Starspots on RS CVn Stars

    NASA Astrophysics Data System (ADS)

    O'Neal, D.; Neff, J. E.; Saar, S. H.

    1997-12-01

    We present results from a study of magnetically active stars using the PHOENIX infrared spectrograph at KPNO. We constrain starspot coverages on RS CVn stars using high-resolution observations of two temperature-sensitive OH lines near 1.563mu m (6397 cm(-1) ). The use of these features holds two advantages over the TiO bands that we have used previously: the OH lines are visible in spots up to ~ 4500 K; and spots are much brighter, relative to the unspotted photosphere, in the infrared than in the visible. These properties also make these OH lines excellent candidates for the first Doppler imaging study to use high-resolution observations of infrared spectral features. Using the OH lines, we also search for previously unknown secondary stars in ``single-lined'' RS CVn binary systems, including II Pegasi (HD 224085).

  3. Near-infrared spectra of Jupiter, Saturn, and Uranus

    NASA Technical Reports Server (NTRS)

    Potter, A. E.

    1974-01-01

    Near infrared spectra of Jupiter, Saturn, and Uranus were measured at resolutions higher than previously available in the range from 6,000 to 10,750/cm. The resolution was 0.5/cm for Jupiter and Saturn, and 32/cm for Uranus. The spectra are presented both individually and as ratio spectra, in which the planetary spectra are divided by the solar spectrum. The Uranus spectrum is shown with Saturn, Jupiter, and Sun spectra reduced to the same resolution so that Uranus can be compared with the other outer planets. The high resolution Saturn, Jupiter, and Sun spectra are presented in parallel plots to simplify comparisons between them.

  4. Increased throughput of proteomics analysis by multiplexing high-resolution tandem mass spectra.

    PubMed

    Ledvina, A R; Savitski, M M; Zubarev, A R; Good, D M; Coon, J J; Zubarev, R A

    2011-10-15

    High-resolution and high-accuracy Fourier transform mass spectrometry (FTMS) is becoming increasingly attractive due to its specificity. However, the speed of tandem FTMS analysis severely limits the competitive advantage of this approach relative to faster low-resolution quadrupole ion trap MS/MS instruments. Here we demonstrate an entirely FTMS-based analysis method with a 2.5-3.0-fold greater throughput than a conventional FT MS/MS approach. The method consists of accumulating together the MS/MS fragments ions from multiple precursors, with subsequent high-resolution analysis of the mixture. Following acquisition, the multiplexed spectrum is deconvoluted into individual MS/MS spectra which are then combined into a single concatenated file and submitted for peptide identification to a search engine. The method is tested both in silico using a database of MS/MS spectra as well as in situ using a modified LTQ Orbitrap mass spectrometer. The performance of the method in the experiment was consistent with theoretical expectations. PMID:21913643

  5. Quantitative Infrared Spectra of Vapor Phase Chemical Agents

    SciTech Connect

    Sharpe, Steven W.; Johnson, Timothy J.; Chu, P M.; Kleimeyer, J; Rowland, Brad; Gardner, Patrick J.

    2003-04-21

    Quantitative high resolution (0.1 cm -1) infrared spectra have been acquired for a number of pressure broadened (101.3 KPa N2), vapor phase chemicals including: Sarin (GB), Soman (GD), Tabun (GA), Cyclosarin (GF), VX, nitrogen mustard (HN3), sulfur mustard (HD) and Lewisite (L).

  6. High resolution n = 3 to n = 2 spectra of neon-like silver

    SciTech Connect

    Beiersdorfer, P.; Bitter, M.; von Goeler, S.; Cohen, S.; Hill, K.W.; Timberlake, J.; Walling, R.S.; Chen, M.H.; Hagelstein, P.L.; Scofield, J.H.

    1986-04-01

    Spectra of the n = 3 to n = 2 transitions in neon-like silver emitted from the Princeton Large Torus have been recorded with a high-resolution Bragg-crystal spectrometer. The measurements cover the wavelength region 3.3 to 4.1 A and include the forbidden 3p ..-->.. 2p electric quadrupole lines. Transitions in the adjacent sodium-like, and aluminum-like charge states of silver have also been observed and identified. The Ly-..cap alpha.. spectra of hydrogen-like argon and iron, the K..cap alpha.. spectra of helium-like argon, potassium, manganese, and iron, and the K..beta.. spectrum of helium-like argon fall in the same wavelength region in first or second order and have been measured concurrently. These spectra provide a coherent set of wavelength reference data obtained with the same spectrometer and from the same tokamak. This set is used as a basis to compare wavelength predictions for one- and two-electron systems to each other and to determine the transition energies of the silver lines with great accuracy.

  7. Inversion of stellar fundamental parameters from ESPaDOnS and Narval high-resolution spectra

    NASA Astrophysics Data System (ADS)

    Paletou, F.; Böhm, T.; Watson, V.; Trouilhet, J.-F.

    2015-01-01

    The general context of this study is the inversion of stellar fundamental parameters from high-resolution Echelle spectra. We aim at developing a fast and reliable tool for the post-processing of spectra produced by ESPaDOnS and Narval spectropolarimeters. Our inversion tool relies on principal component analysis. It allows reducing dimensionality and defining a specific metric for the search of nearest neighbours between an observed spectrum and a set of observed spectra taken from the Elodie stellar library. Effective temperature, surface gravity, total metallicity, and projected rotational velocity are derived. Various tests presented in this study that were based solely on information coming from a spectral band centred on the Mg i b-triplet and had spectra from FGK stars are very promising. Based on observations obtained at the Télescope Bernard Lyot (TBL, Pic du Midi, France), which is operated by the Observatoire Midi-Pyrénées, Université de Toulouse, Centre National de la Recherche Scientifique (France) and the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council of Canada, CNRS/INSU and the University of Hawaii (USA).

  8. Alignment of high resolution magic angle spinning magnetic resonance spectra using warping methods.

    PubMed

    Giskeødegård, Guro F; Bloemberg, Tom G; Postma, Geert; Sitter, Beathe; Tessem, May-Britt; Gribbestad, Ingrid S; Bathen, Tone F; Buydens, Lutgarde M C

    2010-12-17

    The peaks of magnetic resonance (MR) spectra can be shifted due to variations in physiological and experimental conditions, and correcting for misaligned peaks is an important part of data processing prior to multivariate analysis. In this paper, five warping algorithms (icoshift, COW, fastpa, VPdtw and PTW) are compared for their feasibility in aligning spectral peaks in three sets of high resolution magic angle spinning (HR-MAS) MR spectra with different degrees of misalignments, and their merits are discussed. In addition, extraction of information that might be present in the shifts is examined, both for simulated data and the real MR spectra. The generic evaluation methodology employs a number of frequently used quality criteria for evaluation of the alignments, together with PLS-DA to assess the influence of alignment on the classification outcome. Peak alignment greatly improved the internal similarity of the data sets. Especially icoshift and COW seem suitable for aligning HR-MAS MR spectra, possibly because they perform alignment segment-wise. The choice of reference spectrum can influence the alignment result, and it is advisable to test several references. Information from the peak shifts was extracted, and in one case cancer samples were successfully discriminated from normal tissue based on shift information only. Based on these findings, general recommendations for alignment of HR-MAS MRS data are presented. Where possible, observations are generalized to other data types (e.g. chromatographic data). PMID:21094376

  9. CHEMICAL ABUNDANCES IN FIELD RED GIANTS FROM HIGH-RESOLUTION H-BAND SPECTRA USING THE APOGEE SPECTRAL LINELIST

    SciTech Connect

    Smith, Verne V.; Cunha, Katia; Shetrone, Matthew D.; Meszaros, Szabolcs; Allende Prieto, Carlos; Bizyaev, Dmitry; Garcia Perez, Ana; Majewski, Steven R.; Schiavon, Ricardo; Holtzman, Jon; Johnson, Jennifer A.

    2013-03-01

    High-resolution H-band spectra of five bright field K, M, and MS giants, obtained from the archives of the Kitt Peak National Observatory Fourier transform spectrometer, are analyzed to determine chemical abundances of 16 elements. The abundances were derived via spectrum synthesis using the detailed linelist prepared for the Sloan Digital Sky Survey III Apache Point Galactic Evolution Experiment (APOGEE), which is a high-resolution near-infrared spectroscopic survey to derive detailed chemical abundance distributions and precise radial velocities for 100,000 red giants sampling all Galactic stellar populations. The red giant sample studied here was chosen to probe which chemical elements can be derived reliably from the H-band APOGEE spectral region. These red giants consist of two K-giants ({alpha} Boo and {mu} Leo), two M-giants ({beta} And and {delta} Oph), and one thermally pulsing asymptotic giant branch (TP-AGB) star of spectral type MS (HD 199799). Measured chemical abundances include the cosmochemically important isotopes {sup 12}C, {sup 13}C, {sup 14}N, and {sup 16}O, along with Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu. The K and M giants exhibit the abundance signature of the first dredge-up of CN-cycle material, while the TP-AGB star shows clear evidence of the addition of {sup 12}C synthesized during {sup 4}He-burning thermal pulses and subsequent third dredge-up. A comparison of the abundances derived here with published values for these stars reveals consistent results to {approx}0.1 dex. The APOGEE spectral region and linelist is thus well suited for probing both Galactic chemical evolution, as well as internal nucleosynthesis and mixing in populations of red giants via high-resolution spectroscopy.

  10. High-resolution spectroscopy used to measure inertial confinement fusion neutron spectra on Omega (invited).

    PubMed

    Forrest, C J; Radha, P B; Glebov, V Yu; Goncharov, V N; Knauer, J P; Pruyne, A; Romanofsky, M; Sangster, T C; Shoup, M J; Stoeckl, C; Casey, D T; Gatu-Johnson, M; Gardner, S

    2012-10-01

    The areal density (ρR) of cryogenic DT implosions on Omega is inferred by measuring the spectrum of neutrons that elastically scatter off the dense deuterium (D) and tritium (T) fuel. Neutron time-of-flight (nTOF) techniques are used to measure the energy spectrum with high resolution. High signal-to-background data has been recorded on cryogenic DT implosions using a well-collimated 13.4-m line of sight and an nTOF detector with an advanced liquid scintillator compound. An innovative method to analyze the elastically scattered neutron spectra was developed using well-known cross sections of the DT nuclear reactions. The estimated areal densities are consistent with alternative ρR measurements and 1-D simulations. PMID:23126921

  11. High-resolution spectroscopy used to measure inertial confinement fusion neutron spectra on Omega (invited)

    SciTech Connect

    Forrest, C. J.; Radha, P. B.; Glebov, V. Yu.; Goncharov, V. N.; Knauer, J. P.; Pruyne, A.; Romanofsky, M.; Sangster, T. C.; Shoup, M. J. III; Stoeckl, C.; Casey, D. T.; Gatu-Johnson, M.; Gardner, S.

    2012-10-15

    The areal density ({rho}R) of cryogenic DT implosions on Omega is inferred by measuring the spectrum of neutrons that elastically scatter off the dense deuterium (D) and tritium (T) fuel. Neutron time-of-flight (nTOF) techniques are used to measure the energy spectrum with high resolution. High signal-to-background data has been recorded on cryogenic DT implosions using a well-collimated 13.4-m line of sight and an nTOF detector with an advanced liquid scintillator compound. An innovative method to analyze the elastically scattered neutron spectra was developed using well-known cross sections of the DT nuclear reactions. The estimated areal densities are consistent with alternative {rho}R measurements and 1-D simulations.

  12. Synthetic high-resolution near-IR spectra of the Sun for planetary data reductions made from ATMOS/Spacelab-3 and Atlas-3 data

    NASA Astrophysics Data System (ADS)

    Seo, Haingja; Kim, Sang J.; Hwang, Sungwon; Jung, Aeran; Kim, Ji Hyun; Kim, Joo Hyeon; Kim, Kap-Sung; Lee, Jinny; Jang, Minhwan

    2007-12-01

    We have constructed synthetic solar spectra for the 2302-4800 cm -1 (2.08-4.34 μm) range, a spectral range where planetary objects mainly emit reflected sunlight, using ATMOS (Atmospheric Trace Molecule Spectroscopy)/Spacelab-3 and Atlas-3 spectra, of which resolution is 0.01 cm -1. We adopted Voigt line profiles for the modeling of line shapes based on an atlas of line identifications compiled by Geller [Geller, M., 1992. Key to Identification of Solar Features. A High-Resolution Atlas of the Infrared Spectrum of the Sun and the Earth Atmosphere from Space. NASA Reference Publ. 1224, vol. III. NASA, Washington, DC, pp. 1-22], who derived solar line positions and intensities from contaminated high-resolution solar spectra obtained by ATMOS/Spacelab-3. Because the ATMOS spectra in these wavelength ranges are compromised by absorption lines of molecules existing in Earth's high-altitude atmosphere and in the compartment of the spacecraft, the direct use of these high-resolution solar spectra has been inconvenient for the data reductions of planetary spectra. We compared the synthetic solar spectra with the ATMOS spectra, and obtained satisfactory fits for the majority of the solar lines with the exception of abnormal lines, which do not fit with Voigt line profiles. From the model fits, we were able to determine Voigt line parameters for the majority of solar lines; and we made a list of the abnormal lines. We also constructed telluric-line-free solar spectra by manually eliminating telluric lines from the ATMOS spectra and filling the gaps with adjacent continua. These synthetic solar spectra will be useful to eliminate solar continua from spectra of planetary objects to extract their own intrinsic spectral features.

  13. Cool stars: spectral library of high-resolution echelle spectra and database of stellar parameters

    NASA Astrophysics Data System (ADS)

    Montes, D.

    2013-05-01

    During the last years our group have undertake several high resolution spectroscopic surveys of nearby FGKM stars with different spectrographs (FOCES, SARG, SOFIN, FIES, HERMES). A large number of stars have been already observed and we have already determined spectral types, rotational velocities as well as radial velocities, Lithium abundance and several chromospheric activity indicators. We are working now in a homogeneous determination of the fundamental stellar parameters (T_{eff}, log{g}, ξ and [Fe/H]) and chemical abundances of many elements of all these stars. Some fully reduced spectra in FITS format have been available via ftp and in the {http://www.ucm.es/info/Astrof/invest/actividad/spectra.html}{Worl Wide Web} (Montes et al. 1997, A&AS, 123, 473; Montes et al. 1998, A&AS, 128, 485; and Montes et al. 1999, ApJS, 123, 283) and some particular spectral regions of the echelle spectra are available at VizieR by López-Santiago et al. 2010, A&A, 514, A97. We are now working in made accessible all the spectra of our different surveys in a Virtual Observatory ({http://svo.cab.inta-csic.es/}{VO}) compliant library and database accessible using a common web interface following the standards of the International Virtual Observatory Alliance ({http://www.ivoa.net/}{IVOA}). The spectral library includes F, G, K and M field stars, from dwarfs to giants. The spectral coverage is from 3800 to 10000 Å, with spectral resolution ranging from 40000 to 80000. The database will provide in addition the stellar parameters determined for these spectra using {http://cdsads.u-strasbg.fr/abs/2012arXiv1205.4879T}{StePar} (Tabernero et al. 2012, A&A, 547, A13).

  14. Retrieval of upper atmosphere pressure-temperature profiles from high resolution solar occultation spectra

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Russell, J. M., III; Park, J. H.; Namkung, J.

    1987-01-01

    Pressure-temperature profiles over the 18 to 75 km altitude range were retrieved from 0.01 cm(-1) resolution infrared solar absorption spectra recorded with the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectrometer operating in the solar occultation mode during the Spacelab 3 shuttle mission (April 30 to May 1, 1985). The analysis method is described and preliminary results deduced for five occultation events are compared to correlative pressure-temperature measurments.

  15. Time variations of narrow absorption lines in high resolution quasar spectra

    NASA Astrophysics Data System (ADS)

    Boissé, P.; Bergeron, J.; Prochaska, J. X.; Péroux, C.; York, D. G.

    2015-09-01

    Aims: We have searched for temporal variations of narrow absorption lines in high resolution quasar spectra. A sample of five distant sources were assembled, for which two spectra are available, either VLT/UVES or Keck/HIRES, which were taken several years apart. Methods: We first investigate under which conditions variations in absorption line profiles can be detected reliably from high resolution spectra and discuss the implications of changes in terms of small-scale structure within the intervening gas or intrinsic origin. The targets selected allow us to investigate the time behaviour of a broad variety of absorption line systems by sampling diverse environments: the vicinity of active nuclei, galaxy halos, molecular-rich galaxy disks associated with damped Lyα systems, as well as neutral gas within our own Galaxy. Results: Intervening absorption lines from Mg ii, Fe ii, or proxy species with lines of lower opacity tracing the same kind of (moderately ionised) gas appear in general to be remarkably stable (1σ upper limits as low as 10% for some components on scales in the range 10-100 au), even for systems at zabs ≈ ze. Marginal variations are observed for Mg ii lines towards PKS 1229-021 at zabs = 0.83032; however, we detect no systems that display any change as large as those reported in low resolution SDSS spectra. The lack of clear variations for low β Mg ii systems does not support the existence of a specific population of absorbers made of swept-up gas towards blazars. In neutral or diffuse molecular media, clear changes are seen for Galactic Na i lines towards PKS 1229-02 (decrease in N by a factor of four for one of the five components over 9.7 yr), corresponding to structure on a scale of about 35 au, in good agreement with known properties of the Galactic interstellar medium. Tentative variations are detected for H2J = 3 lines towards FBQS J2340-0053 at zabs = 2.05454 (≃35% change in column density, N, over 0.7 yr in the rest frame), suggesting

  16. Determination of atmospheric moisture structure and infrared cooling rates from high resolution MAMS radiance data

    NASA Technical Reports Server (NTRS)

    Menzel, W. Paul; Moeller, Christopher C.; Smith, William L.

    1991-01-01

    This program has applied Multispectral Atmospheric Mapping Sensor (MAMS) high resolution data to the problem of monitoring atmospheric quantities of moisture and radiative flux at small spatial scales. MAMS, with 100-m horizontal resolution in its four infrared channels, was developed to study small scale atmospheric moisture and surface thermal variability, especially as related to the development of clouds, precipitation, and severe storms. High-resolution Interferometer Sounder (HIS) data has been used to develop a high spectral resolution retrieval algorithm for producing vertical profiles of atmospheric temperature and moisture. The results of this program are summarized and a list of publications resulting from this contract is presented. Selected publications are attached as an appendix.

  17. An infrared high resolution silicon immersion grating spectrometer for airborne and space missions

    NASA Astrophysics Data System (ADS)

    Ge, Jian; Zhao, Bo; Powell, Scott; Jiang, Peng; Uzakbaiuly, Berik; Tanner, David

    2014-08-01

    Broad-band infrared (IR) spectroscopy, especially at high spectral resolution, is a largely unexplored area for the far IR (FIR) and submm wavelength region due to the lack of proper grating technology to produce high resolution within the very constrained volume and weight required for space mission instruments. High resolution FIR spectroscopy is an essential tool to resolve many atomic and molecular lines to measure physical and chemical conditions and processes in the environments where galaxy, star and planets form. A silicon immersion grating (SIG), due to its over three times high dispersion over a traditional reflective grating, offers a compact and low cost design of new generation IR high resolution spectrographs for space missions. A prototype SIG high resolution spectrograph, called Florida IR Silicon immersion grating spectromeTer (FIRST), has been developed at UF and was commissioned at a 2 meter robotic telescope at Fairborn Observatory in Arizona. The SIG with 54.74 degree blaze angle, 16.1 l/mm groove density, and 50x86 mm2 grating area has produced R=50,000 in FIRST. The 1.4-1.8 um wavelength region is completely covered in a single exposure with a 2kx2k H2RG IR array. The on-sky performance meets the science requirements for ground-based high resolution spectroscopy. Further studies show that this kind of SIG spectrometer with an airborne 2m class telescope such as SOFIA can offer highly sensitive spectroscopy with R~20,000-30,000 at 20 to 55 microns. Details about the on-sky measurement performance of the FIRST prototype SIG spectrometer and its predicted performance with the SOFIA 2.4m telescope are introduced.

  18. High-resolution spectra of comet C/2013 R1 (Lovejoy)

    NASA Astrophysics Data System (ADS)

    Rousselot, P.; Decock, A.; Jehin, E.; Manfroid, J.; Hutsemékers, D.

    2014-07-01

    Comet C/2013 R1 (Lovejoy) is a long-period comet discovered on 7 September 2013 by Terry Lovejoy with a 0.2-m telescope (Guido et al., 2013), it passed its perihelion (0.81 au) on 22 December 2013. It was a bright comet visible to the naked eye. We obtained high-resolution spectra of this comet immediately after its perihelion passage during 4 nights in the period 23-26 December 2013. These spectra have been obtained with the 3.5-m Telescopio Nazionale Galileo (TNG) and the High Accuracy Radial velocity Planet Searcher in North hemisphere (HARPS-N) echelle spectrograph. HARPS-N is an echelle spectrograph covering the spectral range from 383 to 693 nm, with a spectral resolution of R=115000 (Cosentino et al., 2012). It is designed to measure stellar radial velocities in view of detecting extrasolar planets. Our observations are the first successful cometary observations performed with this instrument. They demonstrate that this spectrograph can also be efficient for getting cometary spectra, even if the sensitivity of this instrument is low in the blue part of its spectral coverage. We will present the results of our data analysis for these spectra. This analysis is focused on isotopic ratios, mainly ^{12}C/^{13}C with C_2 emission lines (with the method described in Rousselot et al. 2012) and ^{14}N/^{15}N with ^{14}NH_2 and ^{15}NH_2 emission lines (with the line wavelengths given in Rousselot et al. 2014), atomic oxygen emission lines at 557.7, 630.0 and 636.4 nm (intensity ratios and widths, see Decock et al. 2013) and relative production rates of the detected species.

  19. High Resolution Observations of Magnetic Elements in the Visible and the Infrared

    NASA Astrophysics Data System (ADS)

    Rimmele, T.; Lin, H.

    1997-05-01

    High resolution observations of magnetic elements in the visible and infrared. We report on multi-wavelength observations of plage regions obtained at the Vacuum Tower Telescope at NSO/Sac-Peak . The data set includes high resolution images in the G-band (0.43 mu ), the visible (0.69 mu ) continuum and the infrared (1.6 mu ) continuum. In addition, deep integration full Stokes vector measurements in the FeI 1.56 mu lines, as well as, Ca-K slit jaw images were obtained. G-band bright points, which are observed mostly in supergranular lanes, are also visible as bright points in the visible continuum. Although the infrared observations are limited in spatial resolution to about 0."4 (the diffraction limit of the VTT/SP), the data indicates that G-band bright points are also bright in the infrared (1.6 mu ). We also discuss and compare properties of magnetic knots and small pores. Magnetic knots, which recently also have been referred to as azimuth centers (Lites et al. 1994), by definition show no darkening in individual continuum images. However, in the time-averaged imaging data, and in particular in the infrared, azimuth centers appear as dark features, which are clearly distinguishable from the quiet sun background. In the infrared most azimuth centers are visible as dark features even in individual snapshots. Many azimuth centers as well as some small pores are surrounded by a highly structured bright ring, which becomes more apparent with increasing height of formation. Results of the polarization analysis in the FeI 1.56 mu lines, including measurements of weak fields, are presented as well.

  20. N to K Uranium PIXE spectra obtained at the high resolution high energy PIXE setup

    NASA Astrophysics Data System (ADS)

    Chaves, P. C.; Taborda, A.; Marques, J. P.; Reis, M. A.

    2014-01-01

    The CTN (previous ITN) high resolution high energy (HRHE) PIXE set-up facility was set in operation on July 2008 and upgrades were being implemented until late in 2011. The study of a pure UO2 sample and the mapping of geological sample are the first results where the whole range of possibilities has been exploited, namely the possibility of obtaining simultaneous spectra covering a very wide energy range of more than 100 keV. In this paper, the N-shell to K-shell spectra of Uranium is presented and discussed, as well as the details on the characteristics and capacities of the setup, including the automated X-Y positioning systems installed in the X-Y-Z sample support unit, which allows for the possibility of making macroscopic mappings of geological samples (Chaves et al. (2013) [1]). As for the N-shell lines in the X-ray Microcalorimeter Spectrometer (XMS) spectrum, due to the lack of data (Zschornack (2007) [2]), transition energies were determined using ab initio calculations assuming a closed shell U4+ electronic structure for Uranium prior to the ionisation by proton impact.

  1. Abundance determinations for the F dwarfs members of the Hyades from SOPHIE high resolution spectra

    NASA Astrophysics Data System (ADS)

    Kılıçǧlu, T.; Monier, R.; Gebran, M.

    2015-12-01

    The mean chemical composition of open clusters can be derived from the chemical abundance analysis of F-type main-sequence stars, as they have convective layers which homogenize the material in their outer layers and thus keep track of the initial composition of the cluster. We present a preliminary abundance analysis of 5 F-type members of the Hyades open cluster using the high resolution spectra retrieved from SOPHIE archive. Our aim is to derive the elemental abundances of these stars as well as the mean abundance distribution of the cluster. The analysis was carried out by iteratively adjusting LTE synthetic spectra for several chemical elements: C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu, and Gd. This is the first abundance determination of the Lanthanides in the Hyades F dwarfs. Each element was found to be marginally/slightly overabundant relative to solar, except for Zn, Ga, Y, and Pr which are solar, and for Sr, Ba, La, Ce, Sm, and Gd which are overabundant. The mean iron abundance of the cluster is found to be [Fe/H] = 0.21 dex.

  2. High-resolution infrared detector and its electronic unit for space application

    NASA Astrophysics Data System (ADS)

    Meftah, M.; Montmessin, F.; Korablev, O.; Trokhimovsky, A.; Poiet, G.; Bel, J.-B.

    2015-05-01

    High-resolution infrared detector is used extensively for military and civilian purposes. Military applications include target acquisition, surveillance, night vision, and tracking. Civilian applications include, among others, scientific observations. For our space systems, we want to use the products developed by SOFRADIR Company. Thus, we have developed a space electronic unit that is used to control the high-resolution SCORPIO-MW infrared detector, which has a format of 640×512 pixels with 15μm×15μm pixel pitch. The detector within microelectronics based on infrared mid-wave (MW) complementary metal oxide semiconductors (CMOS) uses a micro-cooler in order to keep its temperature around 100 K. The standard wavelength range (3 to 5μm) is adapted to the 2.2 to 4.3μm wavelength range thanks to adaptation of the optical interface of the detector and with an antireflection coating. With our electronic system, we can acquire 3 images per second. To increase the signal to noise ratio, we have the opportunity to make a summation of 15 frames per image. Through this article, we will describe the space electronic system that we have developed in order to achieve space observations (e.g. Atmospheric Chemistry Suite package for ExoMars Trace Gas Orbiter).

  3. An abundance study of IC 418 using high-resolution, signal-to-noise emission spectra

    NASA Astrophysics Data System (ADS)

    Sharpee, Brian David

    2003-11-01

    An on-going problem in astrophysics involves the large and varying disagreement between abundances measurements made in planetary nebulae (PNe), determined from the strengths of emission lines arising from the same source ion, but excited by differing mechanisms (recombination and collisional excitation) in planetary nebulae (PNe). We investigate the extent of this problem in IC 418, a PN chosen for its great surface brightness and perceived visually uncomplicated geometry, through the use of high resolution (R ≈ 30000 = 10 km sec-1 at 6500Å) echelle emission spectroscopy in the optical regime (3500 9850Å). These observations allow us to construct the most detailed list of atomic emission lines ever compiled for IC 418, and among the most detailed from among all PNe. Ionic abundances are calculated from the fluxes of numerous weak (1 × 10-5 Hβ) atomic emission lines from the ions of C,N,O, and Ne, using the most recent and accurate atomic transition information presently available. The high resolution of these spectra provides well-defined line profiles, which, coupled with the perceived simplicity of the object's expansion velocity distribution, allows us to better determine where in the nebula lines are formed, and where the ions that produce them are concentrated. Evidence for “non-conventional” line excitation mechanisms, such as continuum fluorescence from the ground state or enhanced dielectronic recombination, is sought in the profile morphologies and relative line strengths. Non-conventional excitation processes may influence the strengths of lines enough to significantly alter abundances calculated from them. Our calculations show that recombination line-derived abundances exceed those derived from collisionally excited lines, for those ions for which we observed lines of both types: O+, O+2, and Ne +2 by real and varying amounts. We find that both continuum fluorescence and dielectronic recombination excites numerous lines in IC 418, but that

  4. Atomic lines in infrared spectra for ultracool dwarfs

    NASA Astrophysics Data System (ADS)

    Lyubchik, Y.; Jones, H. R. A.; Pavlenko, Y. V.; Viti, S.; Pickering, J. C.; Blackwell-Whitehead, R.

    2004-03-01

    We provide a set of atomic lines which are suitable for the description of ultracool dwarf spectra from 10 000 to 25 000 Å. This atomic linelist was made using both synthetic spectra calculations and existing atlases of infrared spectra of Arcturus and Sunspot umbra. We present plots which show the comparison of synthetic spectra and observed Arcturus and Sunspot umbral spectra for all atomic lines likely to be observable in high resolution infrared spectra. Figure 1 is only available in electronic form at http://www.edpsciences.org Tables 1 and 2 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/416/655

  5. Step-stare technique for airborne high-resolution infrared imaging

    NASA Astrophysics Data System (ADS)

    Lavigne, Valerie; Chevrette, Paul C.; Ricard, Benot; Zaccarin, Andre

    2004-08-01

    The Infrared Eye project was developed at DRDC Valcartier to improve the efficiency of airborne search and rescue operations. A high performance opto-mechanical pointing system was developed to allow fast positioning of a narrow field of view with high resolution, used for search and detection, over a wide field of view of lower resolution that optimizes area coverage. This system also enables the use of a step-stare technique, which rapidly builds a large area coverage image mosaic by step-staring a narrow field camera and properly tiling the resulting images. The resulting image mosaic covers the wide field of the current Infrared Eye, but with the high resolution of the narrow field. For the desired application, the camera will be fixed to an airborne platform using a stabilized mount and image positioning in the mosaic will be calculated using flight data provided by an altimeter, a GPS and an inertial unit. This paper presents a model of the complete system, a dynamic step-stare strategy that generates the image mosaic, a flight image taking simulator for strategy testing and some results obtained with this simulator.

  6. Symmetry-Based Tunnelings in High-Resolution Rovibrational Spectra of Octahedral Molecules

    NASA Astrophysics Data System (ADS)

    Mitchell, Justin; Harter, William

    2010-06-01

    High-resolution spectra of spherical-top molecules are known to demonstrate rotational level clustering. This clustering is well described as a rotational phase-space effect Multiple equivalent phase-space regions allow tunneling and thus splitting of the rotational clusters. So far this has been done with an ad hoc tunneling Hamiltonian. Similar splittings have been shown for low dimensional systems, also with an ad hoc parameterization. While ad hoc tunneling parameterization is simple to understand, it becomes extremely difficult to apply for higher symmetries and for locally low-symmetry clustering when many tunneling paths are possible. Symmetry-based parameterization mitigates this complication. This presentation will discuss how symmetry-based tunneling is applied for octahedral molecules and demonstrate how local-C1, C2, C3 or C4 clusters may be evaluated perturbatively. Connections to non-rotational systems, such as large amplitude motion, will be discussed as well. W.G. Harter and C.W. Patterson, Phys Rev Lett 38, 224 (1977) W.G. Harter and C.W. Patterson, J Chem Phys 66, 4872 (1977) J.T. Hougen J Mol Spect 123, 197 (1987)

  7. High-resolution vacuum-ultraviolet photoabsorption spectra of 1-butyne and 2-butyne

    SciTech Connect

    Jacovella, U.; Holland, D. M. P.; Boyé-Péronne, S.; Gans, B.; Oliveira, N. de; Joyeux, D.; Archer, L. E.; Lucchese, R. R.; Xu, H.; Pratt, S. T.

    2015-07-21

    The absolute photoabsorption cross sections of 1- and 2-butyne have been recorded at high resolution by using the vacuum-ultraviolet Fourier-Transform spectrometer at the SOLEIL Synchrotron. Both spectra show more resolved structure than previously observed, especially in the case of 2-butyne. In this work, we assess the potential importance of Rydberg states with higher values of orbital angular momentum, l, than are typically observed in photoabsorption experiments from ground state molecules. We show how the character of the highest occupied molecular orbitals in 1- and 2-butyne suggests the potential importance of transitions to such high-l (l = 3 and 4) Rydberg states. Furthermore, we use theoretical calculations of the partial wave composition of the absorption cross section just above the ionization threshold and the principle of continuity of oscillator strength through an ionization threshold to support this conclusion. The new absolute photoabsorption cross sections are discussed in light of these arguments, and the results are consistent with the expectations. This type of argument should be valuable for assessing the potential importance of different Rydberg series when sufficiently accurate direct quantum chemical calculations are difficult, for example, in the n ≥ 5 manifolds of excited states of larger molecules.

  8. High-resolution Valence and Core Excitation Spectra via First-Principles Calculations and Experiment

    NASA Astrophysics Data System (ADS)

    Shirley, Eric; Fossard, F.; Gilmore, K.; Hug, G.; Kas, J. J.; Rehr, J. J.; Vila, F.

    We calculate the optical and C K-edge near edge spectra of crystalline and molecular C60 measured with high-resolution electron energy-loss spectroscopy. The calculations are carried out using at least three different methods: Bethe-Salpeter calculations using the NIST Bethe-Salpeter Equation solver (NBSE) in the valence and OCEAN (Obtaining Core Excitation with Ab initio methods and NBSE) suite [Gilmore et al., Comp. Phys. Comm., (2015)]; excited-core-hole calculations using XCH [D. Prendergast and G. Galli, Phys. Rev. Lett. 96, 215502 (2006)]; and constrained occupancy using StoBe (Stockholm-Berlin core-excitation code) [StoBe-deMon version 3.0, K. Hermann et al. (2009)]. They include self-energy effects, lifetime-damping, and Debye-Waller effects. A comparison of spectral features to those observed illustrates the sensitivity of certain features to computation details (e.g., self-energy corrections and core-hole screening). This may point to limitations of various approximations, e.g. in conventional BSE paradigm and/or the incomplete treatment of vibrational effects. Supported in part by DOE BES Grant DE-FG03-97ER45623 (JJR, JJK, FV).

  9. Forbidden lines of (O I) in the high-resolution optical spectra of planetary nebulae

    NASA Astrophysics Data System (ADS)

    Keenan, F. P.; Aller, L. H.; Hyung, S.; Brown, P. J. F.

    1995-02-01

    Electron impact excitation rates for transitions in O I, calculated with the R-matrix code, are used to derive the electron-temperature sensitive emission-line ratio R = I(2s22p4 (1D) -2s22p4 1S/2s22p4 (3P)1,2-2s22p4 1D = I(5577 A)/I(6300+6365 A), for a range of electron temperatures Te = 5000-20 000 K) and densities (ne = 104 - 106/cu cm) applicable to planetary nebulae. Experimental values of R for a number of planetaries have been measured from high-resolution (approximately 0.6 A FWHM) spectra obtained with the Hamilton Echelle spectrograph on the 3-m telescope at the Lick Observatory. These measurements should be particularly reliable, as the sample of planetaries was restricted to those with large enough radial velocities for the nebular (O I) 5577 A emission to be red- or blue-shifted from the atmospheric airglow feature by a sufficient amount for the former to be reliably determined. Electron temperatures deduced from the observed values of R are generally in good agreement with those derived from Te-sensitive line ratios in other species, providing observational support for the accuracy of the atomic data adopted in the calculations.

  10. Vibrationally resolved high-resolution NEXAFS and XPS spectra of phenanthrene and coronene

    SciTech Connect

    Fronzoni, Giovanna; Baseggio, Oscar; Stener, Mauro; Hua, Weijie; Tian, Guangjun; Luo, Yi; Apicella, Barbara; Alfé, Michela; Simone, Monica de; Kivimäki, Antti; Coreno, Marcello

    2014-07-28

    We performed a combined experimental and theoretical study of the C1s Near-Edge X-ray Absorption Fine-Structure (NEXAFS) spectroscopy and X-ray Photoelectron Spectroscopy in the gas phase of two polycyclic aromatic hydrocarbons (phenanthrene and coronene), typically formed in combustion reactions. In the NEXAFS of both molecules, a double-peak structure appears in the C1s → LUMO region, which differ by less than 1 eV in transition energies. The vibronic coupling is found to play an important role in such systems. It leads to weakening of the lower-energy peak and strengthening of the higher-energy one because the 0 − n (n > 0) vibrational progressions of the lower-energy peak appear in nearly the same region of the higher-energy peak. Vibrationally resolved theoretical spectra computed within the Frank-Condon (FC) approximation and linear coupling model agree well with the high-resolution experimental results. We find that FC-active normal modes all correspond to in-plane vibrations.

  11. Determination of phosphorus using high-resolution diphosphorus molecular absorption spectra produced in the graphite furnace

    NASA Astrophysics Data System (ADS)

    Huang, Mao Dong; Becker-Ross, Helmut; Okruss, Michael; Geisler, Sebastian; Florek, Stefan

    2016-01-01

    Molecular absorption of diphosphorus was produced in a graphite furnace and evaluated in view of its suitability for phosphorus determination. Measurements were performed with two different high-resolution continuum source absorption spectrometers. The first system is a newly in-house developed simultaneous broad-range spectrograph, which was mainly used for recording overview absorption spectra of P2 between 193 nm and 245 nm. The region covers the main part of the C 1Σu+ ← X 1Σg+ electronic transition and shows a complex structure with many vibrational bands, each consisting of a multitude of sharp rotational lines. With the help of molecular data available for P2, an assignment of the vibrational bands was possible and the rotational structure could be compared with simulated spectra. The second system is a commercial sequential continuum source spectrometer, which was used for the basic analytical measurements. The P2 rotational line at 204.205 nm was selected and systematically evaluated with regard to phosphorus determination. The conditions for P2 generation were optimized and it was found that the combination of a ZrC modified graphite tube and borate as a chemical modifier were essential for a good production of P2. Serious interferences were found in the case of nitrate and sulfuric acid, although the nitrate interference can be eliminated by a higher pyrolysis temperature. The reliability of the method was proved by analysis of certified samples. Using standard tubes, a characteristic mass of 10 ng and a limit of detection of 7 ng were found. The values could further be improved by a factor of ten using a miniaturized tube with an internal diameter of 2 mm. Compared to the conventional method based on the phosphorus absorption line at 213.618 nm, the advantages of using P2 are the gentle temperature conditions and the potential of performing a simultaneous multi-line evaluation to further improve the limit of detection.

  12. Neural network radiative transfer solvers for the generation of high resolution solar irradiance spectra parameterized by cloud and aerosol parameters

    NASA Astrophysics Data System (ADS)

    Taylor, M.; Kosmopoulos, P. G.; Kazadzis, S.; Keramitsoglou, I.; Kiranoudis, C. T.

    2016-01-01

    This paper reports on the development of a neural network (NN) model for instantaneous and accurate estimation of solar radiation spectra and budgets geared toward satellite cloud data using a ≈2.4 M record, high-spectral resolution look up table (LUT) generated with the radiative transfer model libRadtran. Two NN solvers, one for clear sky conditions dominated by aerosol and one for cloudy skies, were trained on a normally-distributed and multiparametric subset of the LUT that spans a very broad class of atmospheric and meteorological conditions as inputs with corresponding high resolution solar irradiance target spectra as outputs. The NN solvers were tested by feeding them with a large (10 K record) "off-grid" random subset of the LUT spanning the training data space, and then comparing simulated outputs with target values provided by the LUT. The NN solvers demonstrated a capability to interpolate accurately over the entire multiparametric space. Once trained, the NN solvers allow for high-speed estimation of solar radiation spectra with high spectral resolution (1 nm) and for a quantification of the effect of aerosol and cloud optical parameters on the solar radiation budget without the need for a massive database. The cloudy sky NN solver was applied to high spatial resolution (54 K pixel) cloud data extracted from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard the geostationary Meteosat Second Generation 3 (MSG3) satellite and demonstrated that coherent maps of spectrally-integrated global horizontal irradiance at this resolution can be produced on the order of 1 min.

  13. Detailed chemical abundances of extragalactic globular clusters using high resolution, integrated light spectra

    NASA Astrophysics Data System (ADS)

    Colucci, Janet E.

    Globular clusters (GCs) are luminous, observationally accessible objects that are good tracers of the total star formation and evolutionary history of galaxies. We present the first detailed chemical abundances for GCs in M31 using a new abundance analysis technique designed for high resolution, integrated light (IL) spectra of GCs. This technique has recently been developed using a training set of old GCS in the Milky Way (MW), and makes possible detailed chemical evolution studies of distant galaxies, where high resolution abundance analysis of individual stars are not obtainable. For the 5 M31 GCs presented here, we measure abundances of 14 elements: Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Y, and Ba. We find the M31 GCs have ages (>10 Gyr) and chemical properties similar to MW GCs, including an enhancement in the alpha-elements Ca, Ti and Si of [alpha/Fe]˜ +0.4. In this thesis, we also further develop this IL abundance analysis method to include GCs of ages 10 Myr--12 Gyrs using GCs in the Large Magellanic Cloud (LMC), which contains the necessary sample of clusters over this wide age range. This work demonstrates for the first time that this IL abundance analysis method can be used on clusters of all ages, and that ages can be constrained to within 1--2 Gyr for clusters with ages of ˜2 Gyr and within a few 100 Myr for clusters with ages <1 Gyr. We find that we can measure [Fe/H] in clusters with ages <12 Gyrs with similar or only slightly larger uncertainties (0.1--0.25 dex) than those obtained for old GCs; the slightly larger uncertainties are due to the rapid evolution in stellar populations at these ages. Using the LMC clusters, we also investigate the effects of statistical fluctuations in the theoretical cluster stellar populations used in our analysis. We also develop strategies to allow for statistical variations in these stellar populations, and find that the stability of the Fe line abundance solution can provide tight constraints on the

  14. High-Resolution FT-IR Spectra of CHF 2Cl in the Region between 335 and 450 cm -1

    NASA Astrophysics Data System (ADS)

    Merke, I.; Graner, G.; Klee, S.; Mellau, G.; Polanz, O.

    1995-10-01

    The spectrum of chlorodifluoromethane (CFC-22) has been investigated in the infrared region. Spectra of CHF 2Cl were recorded at room temperature with high resolution (0.0017 cm -1, Bruker IFS 120 HR) in the region between 335 and 450 cm -1. The spectral analysis of CHF 235Cl (isotopically pure sample) allowed us to assign more than 5500 lines ( J ≤ 76) to the ν 9b-type band (ν 0 = 366.1972 cm -1) and more than 6100 lines ( J ≤ 74) to the ν 6a/ c-hybrid band (ν 0 = 412.9286 cm -1). These two bands interact through both c-type and a-type Coriolis couplings. The addition of microwave and millimeter-wave data (see accompanying paper by Z. Kisiel, L. Pszczółkowski, G. Cazzoli, and G. Cotti, J. Mol. Spectrosc.173, 477-487, 1995) to these IR transitions allowed a global fit to be performed. The resulting molecular parameters are much better defined than when each type of transition is fitted separately. It was also found, by simulating the spectrum, that the dipole moment ratio between the a and c components of ν 6 is about 1.5 and the corresponding ratio of ν 9 and ν 6a is about 2. Moreover, results will be given concerning CHF 237Cl, obtained from a natural abundance sample as well as approximate bandcenters for several hot bands, which were not analyzed in detail.

  15. A Spitzer High-resolution Mid-Infrared Spectral Atlas of Starburst Galaxies

    NASA Astrophysics Data System (ADS)

    Bernard-Salas, J.; Spoon, H. W. W.; Charmandaris, V.; Lebouteiller, V.; Farrah, D.; Devost, D.; Brandl, B. R.; Wu, Yanling; Armus, L.; Hao, L.; Sloan, G. C.; Weedman, D.; Houck, J. R.

    2009-10-01

    We present an atlas of Spitzer/IRS high-resolution (R ~ 600) 10-37 μm spectra for 24 well known starburst galaxies. The spectra are dominated by fine-structure lines, molecular hydrogen lines, and emission bands of polycyclic aromatic hydrocarbons (PAHs). Six out of the eight objects with a known active galactic nucleus (AGN) component show emission of the high excitation [Ne V] line. This line is also seen in one other object (NGC 4194) with, a priori, no known AGN component. In addition to strong PAH emission features in this wavelength range (11.3, 12.7, 16.4 μm), the spectra reveal other weak hydrocarbon features at 10.6, 13.5, 14.2 μm, and a previously unreported emission feature at 10.75 μm. An unidentified absorption feature at 13.7 μm is detected in many of the starbursts. We use the fine-structure lines to derive the abundance of neon and sulfur for 14 objects where the H I 7-6 line is detected. We further use the molecular hydrogen lines to sample the properties of the warm molecular gas. Several basic diagrams characterizing the properties of the sample are also shown. We have combined the spectra of all the pure starburst objects to create a high signal-to-noise ratio template, which is available to the community.

  16. A SPITZER HIGH-RESOLUTION MID-INFRARED SPECTRAL ATLAS OF STARBURST GALAXIES

    SciTech Connect

    Bernard-Salas, J.; Spoon, H. W. W.; Lebouteiller, V.; Farrah, D.; Wu, Yanling; Hao, L.; Sloan, G. C.; Weedman, D.; Houck, J. R.; Charmandaris, V.; Devost, D.; Brandl, B. R.; Armus, L.

    2009-10-01

    We present an atlas of Spitzer/IRS high-resolution (R {approx} 600) 10-37 {mu}m spectra for 24 well known starburst galaxies. The spectra are dominated by fine-structure lines, molecular hydrogen lines, and emission bands of polycyclic aromatic hydrocarbons (PAHs). Six out of the eight objects with a known active galactic nucleus (AGN) component show emission of the high excitation [Ne V] line. This line is also seen in one other object (NGC 4194) with, a priori, no known AGN component. In addition to strong PAH emission features in this wavelength range (11.3, 12.7, 16.4 {mu}m), the spectra reveal other weak hydrocarbon features at 10.6, 13.5, 14.2 {mu}m, and a previously unreported emission feature at 10.75 {mu}m. An unidentified absorption feature at 13.7 {mu}m is detected in many of the starbursts. We use the fine-structure lines to derive the abundance of neon and sulfur for 14 objects where the H I 7-6 line is detected. We further use the molecular hydrogen lines to sample the properties of the warm molecular gas. Several basic diagrams characterizing the properties of the sample are also shown. We have combined the spectra of all the pure starburst objects to create a high signal-to-noise ratio template, which is available to the community.

  17. High Resolution Optical/Near-Infrared Imaging of Cool Ultraluminous Infrared Galaxies

    NASA Technical Reports Server (NTRS)

    Surace, J.; Sanders, D.; Evans, A.

    1999-01-01

    We present here new multiwavelength observations with 1.5 and 4x the spatial resolution of previous ground-based observations at optical and near-infrared wavelengths; despite being ground-based, they allow us to isolate interesting features such as the star-forming knots detected in the warm ULIG sample.

  18. High-Resolution X-Ray Spectra of the Symbiotic Star SS73 17

    NASA Technical Reports Server (NTRS)

    Eze, R. N. C.; Luna, G. J. M.; Smith, R. K.

    2010-01-01

    SS73 17 was an innocuous Mira-type symbiotic star until the International Gamma-Ray Astrophysics Laboratory and Swift discovered its bright hard X-ray emission, adding it to the small class of "hard X-ray emitting symbiotics." Suzaku observations in 2006 then showed it emits three bright iron lines as well, with little to no emission in the 0.3-2.0 keV bandpass. We present here follow-up observations with the Chandra High Energy Transmission Grating and Suzaku that confirm the earlier detection of strong emission lines of Fe K(alpha) fluorescence, Fe XXV and Fe XXVI but also show significantly more soft X-ray emission. The high-resolution spectrum also shows emission lines of other highly ionized ions as Si xiv and possibly S XVI. In addition, a re-analysis of the 2006 Suzaku data using the latest calibration shows that the hard (15-50 keV) X-ray emission is brighter than previously thought and remains constant in both the 2006 and 2008 data. The G ratio calculated from the Fe xxv lines shows that these lines are thermal, not photoionized, in origin.With the exception of the hard X-ray emission, the spectra from both epochs can be fit using thermal radiation assuming a differential emission measure based on a cooling-flow model combined with a full and partial absorber. We show that acceptable fits can be obtained for all the data in the 1-10 keV band varying only the partial absorber. Based on the temperature and accretion rate, the thermal emission appears to be arising from the boundary layer between the accreting white dwarf and the accretion disk.

  19. High-Resolution X-ray Spectra of the Symbiotic Star SS73 17

    NASA Astrophysics Data System (ADS)

    Eze, R. N. C.; Luna, G. J. M.; Smith, R. K.

    2010-02-01

    SS73 17 was an innocuous Mira-type symbiotic star until the International Gamma-Ray Astrophysics Laboratory and Swift discovered its bright hard X-ray emission, adding it to the small class of "hard X-ray emitting symbiotics." Suzaku observations in 2006 then showed it emits three bright iron lines as well, with little to no emission in the 0.3-2.0 keV bandpass. We present here follow-up observations with the Chandra High Energy Transmission Grating and Suzaku that confirm the earlier detection of strong emission lines of Fe Kα fluorescence, Fe XXV and Fe XXVI but also show significantly more soft X-ray emission. The high-resolution spectrum also shows emission lines of other highly ionized ions as Si XIV and possibly S XVI. In addition, a re-analysis of the 2006 Suzaku data using the latest calibration shows that the hard (15-50 keV) X-ray emission is brighter than previously thought and remains constant in both the 2006 and 2008 data. The G ratio calculated from the Fe XXV lines shows that these lines are thermal, not photoionized, in origin. With the exception of the hard X-ray emission, the spectra from both epochs can be fit using thermal radiation assuming a differential emission measure based on a cooling-flow model combined with a full and partial absorber. We show that acceptable fits can be obtained for all the data in the 1-10 keV band varying only the partial absorber. Based on the temperature and accretion rate, the thermal emission appears to be arising from the boundary layer between the accreting white dwarf and the accretion disk.

  20. High-Resolution Spectra and Analysis of the ν 8 Band of Methylene Chloride

    NASA Astrophysics Data System (ADS)

    Morone, A.; Snels, M.; Polanz, O.

    1995-09-01

    The infrared spectra of the ν 8 band of natural methylene chloride and isotopically pure CH 235Cl 2 have been recorded at a resolution of 0.0025 cm -1 in the range 1100-1400 cm -1 with a Bruker IFS 120 HR Fourier transform interferometer. The spectrum of the ν 8 fundamental band has been analyzed for the most abundant isotopic species CH 235Cl 2 and CH 235Cl 37Cl, as well as the ν 4 + ν 8 - ν 4 hot band of CH 235Cl 2. From a rotational analysis, excited state constants up to quartic terms have been obtained, using Watson's A-reduction Hamiltonian in the Ir representation. No perturbations have been observed. The standard deviations of the fits vary from 0.44 × 10 -3 to 0.62 × 10 -3 cm -1.

  1. Fusing electro-optic and infrared signals for high resolution night images

    NASA Astrophysics Data System (ADS)

    Huang, Xiaopeng; Netravali, Ravi; Man, Hong; Lawrence, Victor

    2012-03-01

    Electro-optic (EO) images exhibit the properties of high resolution and low noise level, while it is a challenge to distinguish objects at night through infrared (IR) images, especially for objects with a similar temperature. Therefore, we will propose a novel framework of IR image enhancement based on the information (e.g., edge) from EO images, which will result in high resolution IR images and help us distinguish objects at night. Superimposing the detected edge of the EO image onto the corresponding transformed IR image is our principal idea for the proposed framework. In this framework, we will adopt the theoretical point spread function (PSF) proposed by Russell C. Hardie et al. for our IR image system, which is contributed by the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we will design an inverse filter in terms of the proposed PSF to conduct the IR image transformation. The framework requires four main steps, which are inverse filter-based IR image transformation, EO image edge detection, registration and superimposing of the obtained image pair. Simulation results will show the superimposed IR images.

  2. Mitigating atmospheric effects in high-resolution infra-red surveillance imagery with bispectral speckle imaging

    SciTech Connect

    Carrano, C J

    2006-05-30

    Obtaining a high-resolution image of an object or scene from a long distance away can be very problematic, even with the best optical system. This is because atmospheric blurring and distortion will limit the resolution and contrast of high-resolution imaging systems with substantial sized apertures over horizontal and slant paths. Much of the horizontal and slant-path surveillance imagery we have previously collected and successfully enhanced has been collected at visible wavelengths where atmospheric effects are the strongest. Imaging at longer wavelengths has the benefit of seeing through obscurants or even at night, but even though the atmospheric effects are noticeably reduced, they are nevertheless present, especially near the ground. This paper will describe our recent work on enhanced infrared (IR) surveillance using bispectral speckle imaging. Bispectral speckle imaging in this context is an image postprocessing algorithm that aims to solve the atmospheric blurring and distortion problem of imaging through horizontal or slant path turbulence. A review of the algorithm as well as descriptions of the IR camera and optical systems used in our data collections will be given. Examples of horizontal and slant-path imagery before and after speckle processing will also be presented to demonstrate the resolution improvement gained by the processing. Comparisons of IR imagery to visible wavelength imagery of the same target under the same conditions will be shown to demonstrate the tradeoffs of going to longer wavelengths.

  3. Analysis of high resolution FTIR spectra from synchrotron sources using evolutionary algorithms

    NASA Astrophysics Data System (ADS)

    van Wijngaarden, Jennifer; Desmond, Durell; Leo Meerts, W.

    2015-09-01

    Room temperature Fourier transform infrared spectra of the four-membered heterocycle trimethylene sulfide were collected with a resolution of 0.00096 cm-1 using synchrotron radiation from the Canadian Light Source from 500 to 560 cm-1. The in-plane ring deformation mode (ν13) at ∼529 cm-1 exhibits dense rotational structure due to the presence of ring inversion tunneling and leads to a doubling of all transitions. Preliminary analysis of the experimental spectrum was pursued via traditional methods involving assignment of quantum numbers to individual transitions in order to conduct least squares fitting to determine the spectroscopic parameters. Following this approach, the assignment of 2358 transitions led to the experimental determination of an effective Hamiltonian. This model describes transitions in the P and R branches to J‧ = 60 and Ka‧ = 10 that connect the tunneling split ground and vibrationally excited states of the ν13 band although a small number of low intensity features remained unassigned. The use of evolutionary algorithms (EA) for automated assignment was explored in tandem and yielded a set of spectroscopic constants that re-create this complex experimental spectrum to a similar degree. The EA routine was also applied to the previously well-understood ring puckering vibration of another four-membered ring, azetidine (Zaporozan et al., 2010). This test provided further evidence of the robust nature of the EA method when applied to spectra for which the underlying physics is well understood.

  4. High resolution TE&TM near infrared compact spectrometer based on waveguide grating structures

    NASA Astrophysics Data System (ADS)

    Martin, G.; Thomas, F.; Heidmann, S.; de Mengin, M.; Courjal, N.; Ulliac, G.; Morand, A.; Benech, P.; Kern, P.; Le Coarer, E...

    2015-05-01

    Integrated optics spectrometers can be essentially classified into two main families: based on Fourier transform or dispersed modes. In the first case, an interferogram generated inside an optical waveguide is sampled using nanodetectors, these scatter light into the detector that is in contact with the waveguide. A dedicated FFT processing is needed in order to recover the spectrum with high resolution but limited spectral range. Another way is to extract the optical signal confined in a waveguide using a surface grating and directly obtain the spectrum by means of a relay optics that generates the spectrum on the Fourier plane of the lens, where the detector is placed. Following this second approach, we present a high-resolution compact dispersive spectrometer (δλ =1.5nm at λ=1050nm) based on guided optics technology. The propagating signal is dispersed out of a waveguide thanks to a surface grating that lays along it. Focused Ion Beam technique is used to etch nano-grooves that act as individual scattering centers and constitute the surface grating along the waveguide. The waveguide is realized using X-cut, Ypropagating Lithium Niobate substrate, where the effective index for TE and TM guided modes is different. This results in a strong angular separation of TE and TM diffracted modes, allowing simultaneous detection of spectra for both polarizations. A simple relay optics, with limited optical aberrations, reimages the diffracted signal on the focal plane array, leading to a robust, easy to align instrument.

  5. High resolution Michelson interferometer for airborne infrared astronomical observations. 2: System design.

    PubMed

    Langlet, A; Delage, C; Stefanovitch, D; Talureau, B; Tualy, J; Verveer, J; Fischer, W P; Gilles, J M; Scheper, R; Leblanc, J; Dambier, G

    1977-07-01

    A Michelson interferometer for high resolution (lambda/Deltalambda approximately 10(4)) spectroscopic observations of astronomical ir ionic line emission has been built and flown on the NASA 91-cm airborne ir telescope facility (G. P. Kuiper Airborne Observatory). In Part 1 of this paper the requirements for such a system were outlined, and the scientific basis for the choice of instrumental parameters and the rapid scan mode of operation were discussed. In this paper design details of the instrument are presented. These include the optics, control He-Ne laser interferometer, helium-cooled bolometer detector, and cooled passband filters. In addition, the on-line computer software which enables the operator to interact rapidly with the system to produce inflight spectra and control accordingly the observational parameters is described, as are elements of the electronics hardware developed specially for airborne observations. PMID:20168820

  6. High-resolution solar spectral irradiance from extreme ultraviolet to far infrared

    NASA Astrophysics Data System (ADS)

    Fontenla, J. M.; Harder, J.; Livingston, W.; Snow, M.; Woods, T.

    2011-10-01

    This paper presents new extremely high-resolution solar spectral irradiance (SSI) calculations covering wavelengths from 0.12 nm to 100 micron obtained by the Solar Irradiance Physical Modeling (SRPM) system. Daily solar irradiance spectra were constructed for most of Solar Cycle 23 based on a set of physical models of the solar features and non-LTE calculations of their emitted spectra as function of viewing angle, and solar images specifying the distribution of features on the solar disk. Various observational tests are used to assess the quality of the spectra provided here. The present work emphasizes the effects on the SSI of the upper chromosphere and full-non-LTE radiative transfer calculation of level populations and ionizations that are essential for physically consistent results at UV wavelengths and for deep lines in the visible and IR. This paper also considers the photodissociation continuum opacity of molecular species, e.g., CH and OH, and proposes the consideration of NH photodissociation which can solve the puzzle of the missing near-UV opacity in the spectral range of the near-UV. Finally, this paper is based on physical models of the solar atmosphere and extends the previous lower-layer models into the upper-transition-region and coronal layers that are the dominant source of photons at wavelengths shorter than ˜50 nm (except for the He II 30.4 nm line, mainly formed in the lower-transition-region).

  7. First High-Resolution Infrared Spectroscopic Measurements of Comet 2P/Encke: Unusual Organic Composition and Low Rotational Temperatures

    NASA Astrophysics Data System (ADS)

    Radeva, Yana L.; Mumma, M. J.; Villanueva, G. L.; Bonev, B. P.; DiSanti, M. A.; A'Hearn, M. F.; Dello Russo, N.

    2012-10-01

    We present the first high-resolution infrared spectra of the ecliptic comet 2P/Encke, acquired on UT 4 - 6 Nov. 2003, with the Near Infrared Echelle Spectrograph (NIRSPEC) on the Keck II telescope. 2P/Encke is a dynamical end-member among comets. Its very short period of 3.3 years (with perihelion at 0.34 AU and aphelion at 4.09 AU) exposes the nucleus to unusually high insolation throughout its orbit, raising the prospect that native ices may have experienced significant fractionation over time. Here, we present flux-calibrated spectra, production rates, and mixing ratios for H2O, CH3OH, HCN, H2CO, C2H2, C2H6, CH4 and CO, and compare the abundance ratios with the “organics-normal” population. We also extracted very low rotational temperatures (20 - 30 K) for H2O, HCN, and CH3OH in the near-nucleus coma, which correlate with one of the lowest cometary gas production rates ( 1027 molecules s-1) measured thus far in the infrared. We determined that 2P/Encke is enriched in CH3OH, but depleted in C2H6, C2H2, HCN, CH4, H2CO and CO. We compared mixing ratios of these organic species measured on separate dates, and found no evidence of macroscopic chemical heterogeneity in this cometary nucleus, however, we are limited by sparse temporal sampling of our observations. The depleted abundances of most measured species but retention of the high temperature volatiles (H2O, CH3OH) are consistent with fractionation of 2P/Encke’s native ices by thermal processing while in its current orbit. 2P/Encke is unique in terms of its short period, unusual organic composition, low rotational temperatures and low production rates. The discovery of its unusual organic composition is an important contribution to the emerging chemical taxonomy of comets.

  8. Investigating Possible Departures from Maxwellian Energy Distributions in Nebulae using High-Resolution Emission Line Spectra

    NASA Astrophysics Data System (ADS)

    Turbyfill, Amanda; Dinerstein, H. L.; Sterling, N. C.

    2014-01-01

    The derivation of ionic abundance ratios from collisionally excited emission lines in gaseous nebulae requires knowledge of the physical state of the gas, particularly the electron kinetic temperature, Te, to which the resulting abundances are highly sensitive. A long-standing problem in nebular analyses has been pervasive discrepancies among values of Te obtained from different diagnostic ratios for a single nebula. Recently, Nicholls et al. (2012, ApJ, 752, 148) have suggested that the nebular electrons may not obey an equilibrium Maxwell-Boltzmann (M-B) energy distribution, but instead follow a “κ distribution” seen in many solar system plasmas, a family of distributions for which the M-B distribution is the limiting case where κ → ∞. The high-energy tail of supra-thermal electrons in κ distributions have a disproportionate effect on strongly energy dependent quantities, such as Te diagnostics, for even modest departures from M-B distributions. We apply prescriptions given by Nicholls et al. (2013, ApJS, 207, 21) to high-resolution (R=36,700) optical spectra of 10 planetary nebulae obtained with the 2d-coudé echelle spectrograph on the 2.7 m Harlan J. Smith Telescope at McDonald Observatory. The advantages of these data include their broad spectral coverage and sufficiently high spectral resolution to separate blended lines and assess possible atmospheric absorption issues. The line fluxes were obtained using ROBOSPECT, an automated spectral line measurement package developed by Waters & Hollek (2013, PASP, 125, 1164). We solve both for Te under the assumption of M-B distributions, and the parameters of κ distributions consistent with the data. Our goal is to test whether the κ distribution hypothesis provides a better fit to the observed line ratios. Finally, we discuss effects on the derived ionic abundances under this alternate description of the particle energy distributions. This research was supported by NSF grant AST 0708245 and the John W

  9. A near-infrared high-resolution spectroscopic survey of Galactic bulge stars . - JASMINE prestudy -

    NASA Astrophysics Data System (ADS)

    Tsujimoto, T.; Kobayashi, N.; Ikeda, Y.; Kondo, S.; Yasui, C.; Minami, A.; Motohara, K.; Gouda, N.

    We are developing a new near-infrared high-resolution (R_max= 100,000) and high-sensitive spectrograph WINERED, which is specifically customized for short NIR bands at 0.9-1.35 mu m. WINERED employs the novelty in the optical system; a portable design with a near-infrared immersion grating and warm optics without any cold stops. The planned astrometric space mission JASMINE will provide the exact positions, distances, and proper motions of the Galactic bulge stars. The missing components, the radial velocity and chemical compositions, will be measured by WINERED with high accuracies (delta V< 10km/s). These combined data brought by JASMINE and WINERED will certainly reveal the nature of the Galactic bulge. We plan to complete this instrument with a single slit by the end of 2008 and hope to attach it to various 4-10 m telescopes as a PI-type instrument. In succession, we plan to develop a similar spectrograph but with a simultaneous multi-object spectroscopic capability for full-fledged bulge survey.

  10. Performance of the HIRS/2 instrument on TIROS-N. [High Resolution Infrared Radiation Sounder

    NASA Technical Reports Server (NTRS)

    Koenig, E. W.

    1980-01-01

    The High Resolution Infrared Radiation Sounder (HIRS/2) was developed and flown on the TIROS-N satellite as one means of obtaining atmospheric vertical profile information. The HIRS/2 receives visible and infrared spectrum radiation through a single telescope and selects 20 narrow radiation channels by means of a rotating filter wheel. A passive radiant cooler provides an operating temperature of 106.7 K for the HgCdTe and InSb detectors while the visible detector operates at instrument frame temperature. Low noise amplifiers and digital processing provide 13 bit data for spacecraft data multiplexing and transmission. The qualities of system performance that determine sounding capability are the dynamic range of data collection, the noise equivalent radiance of the system, the registration of the air columns sampled in each channel and the ability to upgrade the calibration of the instrument to maintain the performance standard throughout life. The basic features, operating characteristics and performance of the instrument in test are described. Early orbital information from the TIROS-N launched on October 13, 1978 is given and some observations on system quality are made.

  11. High-resolution microwave and infrared molecular-beam studies of the conformers of 1,1,2,2-tetrafluoroethane

    SciTech Connect

    Stone, S.C.; Philips, L.A.; Fraser, G.T.; Lovas, F.J.

    1996-12-31

    High-resolution microwave and infrared molecular-beam spectra have been measured for 1,1,2,2-tetrafluorethane (HFC134). For the higher-energy, polar, C{sub 1}-symmetry, gauche conformer, microwave spectra have been recorded for the normal and mono-{sup 13}C isotopomers and analyzed to determine a C-C bond length of 1.512(4) {Angstrom} and a CCF angle of 109.7(3){degrees}. A tunable microwave-sideband CO{sub 2} laser and electric-resonance optothermal spectrometer have been used to measure the infrared spectrum of the {nu}{sub 6}, C-C stretch of the gauche conformer near 906 cm{sup -1}. Microwave-infrared double resonance and precise ground-state combination-differences provided by the microwave measurements guide the assignment of the spectrum. A b- and c-type spectrum is observed and fit to a Watson asymmetric-top Hamiltonian to within the experimental uncertainty of 0.3 MHz. The high quality of the fit and the similarity of the centrifugal distortion constants to the ground-state values indicate that the band is effectively unperturbed. A number of strong unassigned lines are present in the spectrum. These transitions do not display any microwave-infrared double resonance effect. The attribution of these transitions to the nonpolar anti conformer is ruled out since the transition intensities are sensitive to the field strength of the inhomogeneous electric field used to focus the molecules. Pulsed slit-jet diode-laser spectra have been recorded for the {nu}{sub 16}, anti conformer near 1127 cm{sup -1}. An a- and c-type hybrid band is observed consistent with previous low-resolution assignments of this vibration to a B. mode. A total of 522 non-blended transitions were assigned and fit to determine ground- and excited-state constants. The ground-state constants of A = 5134.952(65), B = 3148.277(27), and C = 2067.106(43) MHz are the first experimental determination of rotational constants for this conformer.

  12. A high-resolution atlas of the infrared spectrum of the sun and the earth atmosphere from space. A compilation of ATMOS spectra of the region from 650 to 4800 cm-1 (2.3 to 16 μm). Vol. I. The sun.

    NASA Astrophysics Data System (ADS)

    Farmer, C. B.; Norton, R. H.

    1989-08-01

    During the period April 29 through May 2, 1985, the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment was operated as part of the Spacelab-3 payload of the Shuttle Challenger. The instrument, a modified Michelson interferometer covering the frequency range from 600 to 5000 cm-1 (2 to 16 μm) at a spectral resolution of 0.01 cm-1, recorded infrared spectra of the sun and of the earth's atmosphere at times close to entry into and exit from occultation by the earth's limb as seen from the Shuttle orbit of 360 km. Spectra were obtained that are free from absorptions due to constituents of the atmosphere (i.e., they are "pure solar" spectra).

  13. High Resolution Infrared Radiative Transfer of Earth-like planets Influenced by Multiple Clouds

    NASA Astrophysics Data System (ADS)

    Vasquez, Mayte; Schreier, Franz; Trautmann, Thomas; Rauer, Heike; Kitzmann, Daniel; Patzer, A. B. C.; Gimeno Garc&ía, Sebastián.

    2012-07-01

    Background:, The emission spectrum of the modern Earth around different types of stars has been modeled in order to study the effects of different incident stellar radiation in the atmosphere. The Earth-like planetary spectra have also been studied in the presence of clouds. Clouds have an impact on the radiative transfer in planetary atmospheres by changing the spectra (intensities and shapes) due to extinction events (scattering and absorption). Thereby, they can influence the atmospheric and surface temperatures and can also generate false-negative biomarker signatures. Methods:, The spectra of Earth-like have been modeled using a line-by-line radiative transfer model coupled with a multiple scattering solver. The atmospheres of these planets were calculated using a convective climate model taking as reference the atmospheric profile from the modern Earth. All main molecular bands found in the thermal region (H2O, CO2, N2O, CH4 and O3) were analyzed at high resolution in order to assess their detectability in the presence of low (water) and high-level (ice) clouds for different percent coverage. Results:, The resulting calculations indicate that the modern Earth spectrum for a cloud-free atmosphere changes in the presence of different stellar types. The pressure-temperature profile and the molecular concentrations of the Earth were altered. In the presence of clouds, the atmospheric temperatures were modified as well. The water cloud cooled down the surface and tropospheric temperatures of the planets while the ice cloud warmed them up. The presence of clouds also decreased the depth of the absorption bands and modified their shapes, consequently producing a false-negative detection of some of the bands. Keywords:, radiation, planets, atmospheres, clouds, aerosols, molecules, scattering, habitability, modeling.

  14. A high-resolution near-infrared extraterrestrial solar spectrum derived from ground-based Fourier transform spectrometer measurements

    NASA Astrophysics Data System (ADS)

    Menang, Kaah P.; Coleman, Marc D.; Gardiner, Tom D.; Ptashnik, Igor V.; Shine, Keith P.

    2013-06-01

    A detailed spectrally resolved extraterrestrial solar spectrum (ESS) is important for line-by-line radiative transfer modeling in the near-IR. Very few observationally based high-resolution ESS are available in this spectral region. Consequently, the theoretically calculated ESS by Kurucz has been widely adopted. We present the CAVIAR (Continuum Absorption at Visible and Infrared Wavelengths and its Atmospheric Relevance) ESS, which is derived using the Langley technique applied to calibrated observations using a ground-based high-resolution Fourier transform spectrometer (FTS) in atmospheric windows from 2000 to 10,000 cm-1 (1-5 µm). There is good agreement between the strengths and positions of solar lines between the CAVIAR and the satellite-based Atmospheric Chemistry Experiment-FTS ESS, in the spectral region where they overlap, and good agreement with other ground-based FTS measurements in two near-IR windows. However, there are significant differences in the structure between the CAVIAR ESS and spectra from semiempirical models. In addition, we found a difference of up to 8% in the absolute (and hence the wavelength-integrated) irradiance between the CAVIAR ESS and that of Thuillier et al., which was based on measurements from the Atmospheric Laboratory for Applications and Science satellite and other sources. In many spectral regions, this difference is significant, because the coverage factor k = 2 (or 95% confidence limit) uncertainties in the two sets of observations do not overlap. Because the total solar irradiance is relatively well constrained, if the CAVIAR ESS is correct, then this would indicate an integrated "loss" of solar irradiance of about 30 W m-2 in the near-IR that would have to be compensated by an increase at other wavelengths.

  15. Package for Interactive Analysis of Line Emission (Analysis of UV-X-Ray High-Resolution Emission Spectra)

    NASA Technical Reports Server (NTRS)

    Hunter, Paul (Technical Monitor); Kashyap, Vinay

    2004-01-01

    The Package for Interactive Analysis of Line Emission (PINTofALE) is a suite of IDL routines designed to carry out spectroscopic analysis of high-resolution X-ray spectra. The current version is 1.5, and will shortly be upgraded to v2. A detailed description of the package, together with detailed documentation, example walk-throughs, science threads, and downloadable tar files, are available on-line.

  16. HIGH-RESOLUTION, DIFFERENTIAL, NEAR-INFRARED TRANSMISSION SPECTROSCOPY OF GJ 1214b

    SciTech Connect

    Crossfield, I. J. M.; Hansen, Brad M. S.; Barman, Travis

    2011-08-01

    The nearby star GJ 1214 hosts a planet intermediate in radius and mass between Earth and Neptune, resulting in some uncertainty as to its nature. We have observed this planet, GJ 1214b, during transit with the high-resolution, near-infrared NIRSPEC spectrograph on the Keck II telescope, in order to characterize the planet's atmosphere. By cross-correlating the spectral changes through transit with a suite of theoretical atmosphere models, we search for variations associated with absorption in the planet atmosphere. Our observations are sufficient to rule out tested model atmospheres with wavelength-dependent transit depth variations {approx}> 5 x 10{sup -4} over the wavelength range 2.1-2.4 {mu}m. Our sensitivity is limited by variable slit loss and telluric transmission effects. We find no positive signatures but successfully rule out a number of plausible atmospheric models, including the default assumption of a gaseous, H-dominated atmosphere in chemical equilibrium. Such an atmosphere can be made consistent if the absorption due to methane is reduced. Clouds can also render such an atmosphere consistent with our observations, but only if they lie higher in the atmosphere than indicated by recent optical and infrared measurements. When taken in concert with other observational constraints, our results support a model in which the atmosphere of GJ 1214b contains significant H and He, but where CH{sub 4} is depleted. If this depletion is the result of photochemical processes, it may also produce a haze that suppresses spectral features in the optical.

  17. High-resolution infrared spectroscopy and ab initio studies of the cyclopropane-carbon dioxide interaction.

    PubMed

    Su, Zheng; Tam, Wai Shun; Xu, Yunjie

    2006-01-14

    A jet-cooled high-resolution infrared spectrum of the cyclopropane-carbon dioxide complex was detected for the first time, using a rapid scan infrared spectrometer with an astigmatic multipass sample cell. The spectrum was recorded in the vicinity of the CO2 asymmetric stretching band (nu3) and exhibits a b-dipole selection rule. Altogether, over 200 lines were observed, assigned, and fitted to Watson's S-reduction Hamiltonian. Rotational and quartic distortion constants were obtained. The band origin was located at 2347.6263(2) cm(-1), redshifted by 1.5230(2) cm(-1) from the corresponding frequency of the CO2 monomer. The experimentally determined structure shows that CO2 lies next to a C-C bond edge and is perpendicular to the C3 ring, indicating that the interaction is characterized by the bonding between the carbon atom of CO2 and the pseudo-pi system of cyclopropane. The intermolecular distance between the carbon atom of CO2 and the center of mass of cyclopropane was determined to be 3.667(2) A. Complete ab initio geometry optimizations and harmonic frequency calculations were carried out at the level of second-order Moller-Plesset perturbation theory with four different basis sets: cc-pVDZ, 6-311++G(d,p), aug-cc-pVDZ, and aug-cc-pVTZ. The lowest-energy structure identified with the three larger basis sets is in accord with the experimental finding. In addition, a transition state was identified and the tunneling barrier height was computed. PMID:16422587

  18. High-Resolution Microwave and Infrared Molecular-Beam Studies of the Conformers of 1,1,2,2-Tetrafluoroethane

    NASA Astrophysics Data System (ADS)

    Stone, Stephen C.; Philips, Laura A.; Fraser, G. T.; Lovas, F. J.; Xu, Li-Hong; Sharpe, S. W.

    1998-11-01

    High-resolution microwave and infrared molecular-beam spectra have been measured for 1,1,2,2-tetrafluoroethane (HFC134). For the higher energy, polar,C2symmetry,gaucheconformer, microwave spectra have been recorded for the normal and mono-13C isotopomers and analyzed to determine a C-C bond length of 1.512(4) Å, in good agreement with a recentab initiovalue (MP2/6-31G**) of 1.515 Å [S. Papasavva, K. H. Illinger, and J. E. Kenny,J. Phys. Chem.100, 10100-10110 (1996)]. A tunable microwave-sideband CO2laser and electric-resonance optothermal spectrometer have been used to measure the infrared spectrum of the ν6, C-C stretch of thegaucheconformer near 906 cm-1. Microwave-infrared double resonance and precise ground state combination differences provided by the microwave measurements guide the assignment of the spectrum. The observation of ac-type spectrum definitively establishes that the upper state vibration is ofAsymmetry in theC2point group. The spectrum is fit to a Watson asymmetric-top Hamiltonian to a standard deviation of 0.24 MHz. A weak perturbation shifts the line positions for transitions nearJ = Kc= 20 by as much as 12 MHz. The identity of the perturber is unknown. Pulsed slit-jet diode-laser spectra have been recorded for the ν16vibration of theanticonformer near 1127 cm-1. Ana- andc-type hybrid band is observed, consistent with aBusymmetry mode. Previous low-resolution studies have attributed the 1127-cm-1mode to either aBuor anAusymmetry vibration. A total of 522 nonblended transitions were assigned and fit to determine ground and excited state constants. The ground state constants ofA= 5134.952(65) MHz,B= 3148.277(27) MHz, andC= 2067.106(43) MHz are the first experimental determinations of the rotational constants for this conformer. Here, typeAstandard uncertainties are given in the parentheses.

  19. High-Resolution Microwave and Infrared Molecular Beam Studies of the Conformers of 1, 1, 2, 2-Tetrafluoroethane

    SciTech Connect

    Stone, Steven C.; Philips, Laura A.; Fraser, Gerry; Lovas, Fj; Xu, Li-Hong; Sharpe, Steven W.)

    1998-01-01

    High-resolution microwave and infrared molecular-beam spectra have been measure for 1,1,2,2-tetraflouroethane (HFC134). For the higher energy, polar, C2 symmetry, gauche conformer, microwave spectra have been recorded for the normal and mono-13C isotopomers and analyzed to determine a C-C bond length of 1.512(4)?, in good agreement with a recent ab initio value (MP2/6-31**) of 1.515?[S. Papasavva, K.H. Illinger, and J.E. Kenny, J. Phys. Chem 100 10100-10110(1996)]. A tunable microwave-sideband CO2 laser and electric-resonance optethermal spectrometer have been used to measure the infrared spectrum of the v6, C-C stretch of the gauche conformer near 906 cm-1. Microwave-infrared double resonance and precise ground state combination differences provided by the microwave measurements guide the assignment of the spectrum. The observation of a c-type spectrum definitively establishes that the upper state vibration is of A symmetry in the C2 point group. The spectrum is fit to a Watson asymmetric-top Hamiltonian to a standard deviation of 0.24 MHz. A weak perturbation shifts the line positions for transitions near J=Kc=20 by as much as 12 MHz. The identity of the perturber is unknown. Pulsed slit-jet diode-laser spectra have been recorded for the v16 vibration of the anti conformer near 1127 cm-1. An a- and c-type hybrid band is observed, consistent with a Bu symmetry mode. Previous low-resolution studies have attributed the 1127-cm-1 mode to either a Bu or an Au symmetry vibration. A total of 522 nonblended transitions were assigned and fit to determine ground and excited state constants. The ground state constants of A=52 5.952(65) MHz, B= 3148.277(27) MHz, and C= 2067.106(43) MHz are the first experimental determinations of the rotational constants for this conformer. Here, type A standard uncertainties are given in the parenthese.

  20. A high-resolution atlas of the infrared spectrum of the sun and the earth atmosphere from space. A compilation of ATMOS spectra of the region from 650 to 4800 cm-1 (2.3 to 16 microns). Volume 2: Stratosphere and mesosphere, 650 to 3350 cm-1

    NASA Technical Reports Server (NTRS)

    Farmer, Crofton B.; Norton, Robert H.

    1989-01-01

    During the period April 29 to May 2, 1985, the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment was operated for the first time, as part of the Spacelab-3 payload of the shuttle Challenger. The principal purpose of this experiment was to study the distributions of the atmosphere's minor and trace molecular constituents. The instrument, a modified Michelson interferometer covering the frequency range from 600 to 5000/cm-1 at a spectral resolution of 0.01/cm-1, recorded infrared absorption spectra of the sun and of the earth's atmosphere at times close to entry into and exit from occultation by the earth's limb. Spectra were obtained that are free from absorptions due to constituents of the atmosphere (i.e., they are pure solar spectra), as well as spectra of the atmosphere itself, covering line-of-sight tangent altitudes that span the range from the lower thermosphere to the bottom of the troposphere. This atlas presents a compilation of these spectra arranged in a hardcopy format suitable for quick-look reference purposes. Volume 2 covers the stratosphere and mesosphere (i.e., tangent altitudes from 20 to 80 km) for frequencies from 650 to 3350/cm-1.

  1. A high-resolution atlas of the infrared spectrum of the sun and the earth atmosphere from space. A compilation of ATMOS spectra of the region from 650 to 4800 cm-1 (2.3 to 16 microns). Volume 2: Stratosphere and mesosphere, 650 to 3350 cm-1

    NASA Astrophysics Data System (ADS)

    Farmer, Crofton B.; Norton, Robert H.

    During the period April 29 to May 2, 1985, the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment was operated for the first time, as part of the Spacelab-3 payload of the shuttle Challenger. The principal purpose of this experiment was to study the distributions of the atmosphere's minor and trace molecular constituents. The instrument, a modified Michelson interferometer covering the frequency range from 600 to 5000/cm-1 at a spectral resolution of 0.01/cm-1, recorded infrared absorption spectra of the sun and of the earth's atmosphere at times close to entry into and exit from occultation by the earth's limb. Spectra were obtained that are free from absorptions due to constituents of the atmosphere (i.e., they are pure solar spectra), as well as spectra of the atmosphere itself, covering line-of-sight tangent altitudes that span the range from the lower thermosphere to the bottom of the troposphere. This atlas presents a compilation of these spectra arranged in a hardcopy format suitable for quick-look reference purposes. Volume 2 covers the stratosphere and mesosphere (i.e., tangent altitudes from 20 to 80 km) for frequencies from 650 to 3350/cm-1.

  2. A near-infrared high-resolution spectroscopic survey of bulge stars - JASMINE prestudy

    NASA Astrophysics Data System (ADS)

    Tsujimoto, T.; Gouda, N.; Kobayashi, N.; Yasui, C.; Kondo, S.; Minami, A.; Motohara, K.; Ikeda, Y.

    2006-08-01

    We are developing a new near-infrared high-resolution (R[max]= 100,000) and high-sensitive spectrograph WINERED, which is specifically customized for short NIR bands at 0.9-1.35 μm. WINERED employs the novelty in the optical system; a potable design and a warm optics without any cold stops. The planned astrometric space mission JASMINE will provide the exact positions, distances, and proper motions of the bulge stars. The missing components, the radial velocity and chemical compositions will be measured by WINERED with high accuracies (δV< 1km/s). These combined data brought by JASMINE and WINERED will certainly reveal the nature of the Galactic bulge. We plan to complete this instrument for the observation of a single object by the end of 2008 and hope to attach it to various 4-10m telescopes as a PI-type instrument. In succession, we will develop it to the design for a simultaneous multi-object spectroscopy.

  3. TOWARD UNDERSTANDING THE ENVIRONMENT OF R MONOCEROTIS FROM HIGH-RESOLUTION NEAR-INFRARED POLARIMETRIC OBSERVATIONS

    SciTech Connect

    Jolin, M.-A.; Bastien, P.; Denni, F.; Lafreniere, D.; Doyon, R.; Voyer, P.

    2010-10-01

    High-resolution H-band imaging polarimetric observations of R Mon obtained at the Canada-France-Hawaii telescope are presented. These data show a centrosymmetric pattern with elongated intensity contours mostly due to the presence of the companion R Mon B. We also consider published R-band data, which show an extended right-angle conical reflection nebula with an offset in the optical peak. We study the circumstellar environment of R Mon with a radiative transfer Monte Carlo code. The best-fitting model obtained succeeds in reproducing the characteristics seen in the data in the two bands simultaneously. The model indicates the presence of relatively small astronomical silicate grains ranging from 0.04 {mu}m to 0.15 {mu}m distributed into three structures: a small disk, an inner envelope, and an outer envelope. The cavity is modeled by a conical structure with a constant low density and we include a 'throat' to produce the offset of the optical peak. Our model predicts a polarization reversal by 90{sup 0} between the R and H bands. Observations show that position angles parallel, perpendicular, and also at other angles to the disk can occur over time in the near-infrared.

  4. A high-resolution study of near-infrared diffuse interstellar bands

    SciTech Connect

    Rawlings, M. G.; Adamson, A. J.; Kerr, T. H. E-mail: aadamson@gemini.edu

    2014-11-20

    We present high-resolution echelle spectroscopic observations of the two near-infrared (NIR) diffuse interstellar bands (DIBs) at 13175 Å and 11797.5 Å. The DIBs have been observed in a number of diffuse interstellar medium sightlines that exhibit a wide range of visual extinctions. Band profiles are similar to those seen in narrow DIBs, clearly asymmetric and can be closely fitted in most cases using two simple Gaussian components. Gaussian fits were generally found to be more successful than fits based on a multiple-cloud model using a template DIB profile. For a sample of nine objects in which both bands are observed, the strength of both NIR DIBs generally increases with A(V), and we report a correlation between the two observed bands over a large A(V) range and widely separated lines of sight. The strength of the two bands is also compared against those of two visual DIBs and the diffuse ISM aliphatic dust absorption feature at 3.4 μm previously detected in the same sightlines. We find that the NIR DIBs do not exhibit notable (anti)correlations with either. Implications of these observations on possible DIB carrier species are discussed.

  5. Multi-sensor fusion of infrared and electro-optic signals for high resolution night images.

    PubMed

    Huang, Xiaopeng; Netravali, Ravi; Man, Hong; Lawrence, Victor

    2012-01-01

    Electro-optic (EO) image sensors exhibit the properties of high resolution and low noise level at daytime, but they do not work in dark environments. Infrared (IR) image sensors exhibit poor resolution and cannot separate objects with similar temperature. Therefore, we propose a novel framework of IR image enhancement based on the information (e.g., edge) from EO images, which improves the resolution of IR images and helps us distinguish objects at night. Our framework superimposing/blending the edges of the EO image onto the corresponding transformed IR image improves their resolution. In this framework, we adopt the theoretical point spread function (PSF) proposed by Hardie et al. for the IR image, which has the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we design an inverse filter for the proposed PSF and use it for the IR image transformation. The framework requires four main steps: (1) inverse filter-based IR image transformation; (2) EO image edge detection; (3) registration; and (4) blending/superimposing of the obtained image pair. Simulation results show both blended and superimposed IR images, and demonstrate that blended IR images have better quality over the superimposed images. Additionally, based on the same steps, simulation result shows a blended IR image of better quality when only the original IR image is available. PMID:23112602

  6. Improved fusing infrared and electro-optic signals for high-resolution night images

    NASA Astrophysics Data System (ADS)

    Huang, Xiaopeng; Netravali, Ravi; Man, Hong; Lawrence, Victor

    2012-06-01

    Electro-optic (EO) images exhibit the properties of high resolution and low noise level, while it is a challenge to distinguish objects with infrared (IR), especially for objects with similar temperatures. In earlier work, we proposed a novel framework for IR image enhancement based on the information (e.g., edge) from EO images. Our framework superimposed the detected edges of the EO image with the corresponding transformed IR image. Obviously, this framework resulted in better resolution IR images that help distinguish objects at night. For our IR image system, we used the theoretical point spread function (PSF) proposed by Russell C. Hardie et al., which is composed of the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we designed an inverse filter based on the proposed PSF to transform the IR image. In this paper, blending the detected edge of the EO image with the corresponding transformed IR image and the original IR image is the principal idea for improving the previous framework. This improved framework requires four main steps: (1) inverse filter-based IR image transformation, (2) image edge detection, (3) images registration, and (4) blending of the corresponding images. Simulation results show that blended IR images have better quality over the superimposed images that were generated under the previous framework. Based on the same steps, the simulation result shows a blended IR image of better quality when only the original IR image is available.

  7. Multi-Sensor Fusion of Infrared and Electro-Optic Signals for High Resolution Night Images

    PubMed Central

    Huang, Xiaopeng; Netravali, Ravi; Man, Hong; Lawrence, Victor

    2012-01-01

    Electro-optic (EO) image sensors exhibit the properties of high resolution and low noise level at daytime, but they do not work in dark environments. Infrared (IR) image sensors exhibit poor resolution and cannot separate objects with similar temperature. Therefore, we propose a novel framework of IR image enhancement based on the information (e.g., edge) from EO images, which improves the resolution of IR images and helps us distinguish objects at night. Our framework superimposing/blending the edges of the EO image onto the corresponding transformed IR image improves their resolution. In this framework, we adopt the theoretical point spread function (PSF) proposed by Hardie et al. for the IR image, which has the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we design an inverse filter for the proposed PSF and use it for the IR image transformation. The framework requires four main steps: (1) inverse filter-based IR image transformation; (2) EO image edge detection; (3) registration; and (4) blending/superimposing of the obtained image pair. Simulation results show both blended and superimposed IR images, and demonstrate that blended IR images have better quality over the superimposed images. Additionally, based on the same steps, simulation result shows a blended IR image of better quality when only the original IR image is available. PMID:23112602

  8. A modularized infrared light matrix system with high resolution for measuring animal behaviors.

    PubMed

    Young, M S; Li, Y C; Lin, M T

    1993-03-01

    The current study provides a new modularized infrared light matrix system (about $200 cost) which is designed to measure the horizontal gross or fine movements, vertical motion, clockwise or anticlockwise turnings, freezing time, and total distance traveled in rats. The system records the sequences of animal's activity in a computer-aided system with a resolution of 0.2 s in time or 1.6 cm in space, and permanently stores all the resulting data in file. The behavioral apparatus was tested for its sensitivity and usability by amphetamine-injected rats. It was found that intraperitoneal administration of amphetamine (1.25-2.50 mg/kg), but not normal saline, produced a dose-related increase in either the horizontal gross or fine movements, vertical motion, clockwise or anticlockwise turnings, or total distance traveled. However, amphetamine injections produced a dose-related decrease in freezing time. Apparently, most of the amphetamine-induced responses obtained by other detecting apparatus can be reproduced easily by the present apparatus. The current detection system possesses the following advantages: a) high resolution, b) high expansion potential, and c) precise and simplified algorithms for behavioral parameter analysis. PMID:8451322

  9. Exploring the transition to planetary nebula using high-resolution techniques at infrared wavelengths

    NASA Astrophysics Data System (ADS)

    Wendolyn Blanco Cárdenas, Mónica

    2015-08-01

    A planetary nebula (PN) is the ionised envelope surrounding a white dwarf, the final fate of low- and intermediate-mass stars. This stellar phase is also important for its contribution to the interstellar medium, when PNe drive out s-process elements, molecules as well as different dust species, the building blocks of life. One of the most discussed topics in the PNe research field is their huge variety of morphologies and how the more complex forms are sculpted. The theoretical models predict the existence of collimating agents such as disks (steady and/or rotating), jets, and binary systems to sculpt these perplexing morphologies. However, the observations able to detect these shaping engines are often quite difficult to accomplish. Furthermore, the transition to PN hides the clues of these process, that is, when the AGB, post-AGBs, proto-PN, and the circumstellar environments of young PNe are compact and embeded in dust. In this work, we present our results implementing observational techniques and different analysis to inspect and resolve these structures by means of high-resolution imaging, high- and low-resolution spectroscopy at infrared wavelengths and using two VLT instruments: CRIRES (near-IR) and VISIR (mid-IR).

  10. VizieR Online Data Catalog: High resolution spectra of 3 NGC104 member stars (Ferraro+, 2016)

    NASA Astrophysics Data System (ADS)

    Ferraro, F. R.; Lapenna, E.; Mucciarelli, A.; Lanzoni, B.; Dalessandro, E.; Pallanca, C.; Massari, D.

    2016-03-01

    In the context of the ESO Large Programme 193.D-0232 (PI: Ferraro) aimed at studying the internal kinematics of Galactic globular clusters, we have secured UVES-FLAMES high-resolution spectra of three stars in 47 Tuc (NGC 104). The (V,V-I) CMD is obtained from the Hubble Space Telescope (HST)-Advanced Camera for Surveys (ACS) photometric catalog of Sarajedini et al. (2007AJ....133.1658S). The target spectra have been acquired with the grating 580 Red Arm CD#3, which provides a spectral resolution R~40000 between 4800 and 6800Å. The three stars are all cluster members. (2 data files).

  11. High-resolution infrared spectrum of triacetylene: The ν5 state revisited and new vibrational states

    NASA Astrophysics Data System (ADS)

    Doney, K. D.; Zhao, D.; Linnartz, H.

    2015-10-01

    New data are presented that follow from a high-resolution survey, from 3302 to 3352 cm-1, through expanding acetylene plasma, and covering the Csbnd H asymmetric (ν5) fundamental band of triacetylene (HC6H). Absorption signals are recorded using continuous wave cavity ring-down spectroscopy (cw-CRDS). A detailed analysis of the resulting spectra allows revisiting the molecular parameters of the ν5 fundamental band in terms of interactions with a perturbing state, which is observed for the first time. Moreover, four fully resolved hot bands (501 1011, 501 1111, 501 1311, and 101 801 1110), with band origins at 3328.5829(2), 3328.9994(2), 3328.2137(2) and 3310.8104(2) cm-1, respectively, are reported for the first time. These involve low lying bending vibrations that have been studied previously, which guarantees unambiguous identifications. Combining available data allows to derive accurate molecular parameters, both for the ground state as well as the excited states involved in the bands.

  12. High-resolution infrared studies of perdeutero-spiropentane, C5D8

    NASA Astrophysics Data System (ADS)

    Erickson, B. A.; Ju, X.; Nibler, J. W.; Beaudry, C. M.; Blake, T. A.

    2016-07-01

    Perdeutero-spiropentane (C5D8) has been synthesized, and infrared and Raman spectra are reported for the first time. Wavenumber assignments are made for most of the fundamental vibrational states. Gas phase infrared spectra were recorded at a resolution (0.002 cm-1) sufficient to resolve individual rovibrational lines and show evidence of strong Coriolis and/or Fermi resonance interactions for most bands. However a detailed rovibrational analysis of the fundamental ν15 (b2) parallel band proved possible, and a fit of more than 1600 lines yielded a band origin of 1053.84465(10) cm-1 and ground state constants (in units of cm-1): B0 = 0.1120700(9), DJ = 1.51(3) × 10-8, DJK = 3.42(15) × 10-8. We note that the B0 value is significantly less than a value of Ba = 0.1140 cm-1 calculated using structural parameters from an earlier electron diffraction (ED) study, whereas one expects Ba to be lower than B0 because of thermal averaging over higher vibrational levels. A similar discrepancy was noted in an earlier study of C5H8 (Price et al., 2011). The structural and spectroscopic results are in good accord with values computed at the anharmonic level using the B3LYP density functional method with a cc-pVTZ basis set.

  13. An in-depth look at the lunar crater Copernicus: Exposed mineralogy by high-resolution near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Bugiolacchi, Roberto; Mall, Urs; Bhatt, Megha; McKenna-Lawlor, Susan; Banaszkiewicz, Marek; Brønstad, Kjell; Nathues, Andreas; Søraas, Finn; Ullaland, Kjetil; Pedersen, Rolf B.

    2011-05-01

    Newly acquired, sequentially spaced, high-resolution near-infrared spectra across the central section of crater Copernicus' interior have been analyzed using a range of complementary techniques and indexes. We have developed a new interpretative method based on a multiple stage normalization process that appears to both confirm and expand on previous mineralogical estimations and mapping. In broad terms, the interpreted distribution of the principle mafic species suggests an overall composition of surface materials dominated by calcium-poor pyroxenes and minor olivine but with notable exceptions: the southern rim displays strong ca-rich pyroxene absorption features and five other locations, the uppermost northern crater wall, opposite rim sections facing the crater floor, and the central peak Pk1 and at the foot of Pk3, show instead strong olivine signatures. We also propose impact glass an alternative interpretation to the source of the weak but widespread olivine-like spectral signature found in low-reflectance samples, since it probably represents a major regolith constituent and component in large craters such as Copernicus. The high quality and performance of the SIR-2 data allows for the detection of diagnostic key mineral species even when investigating spectral samples with very subdued absorption features, confirming the intrinsic high-quality value of the returned data.

  14. High Resolution Near-Infrared Spectroscopy of Comet C/2013 R1 (Lovejoy) using WINERED at Koyama Astronomical Observatory

    NASA Astrophysics Data System (ADS)

    Kawakita, Hideyo; Shinnaka, Yoshiharu; Ogawa, Sayuri; Kobayashi, Hitomi; Kondo, Sohei; Nakanishi, Kenshi; Kawanishi, Takafumi; Nakaoka, Tetsuya; Otsubo, Shogo; Kinoshita, Masaomi; Ikeda, Yuji; Yamamoto, Ryo; Izumi, Natsuko; Fukue, Kei; Hamano, Satoshi; Yasui, Chikako; Mito, Hiroyuki; Matsunaga, Noriyuki; Kobayashi, Naoto

    2014-11-01

    High resolution near-infrared spectroscopic observations of comet C/2013 R1 (Lovejoy) using the WINERED ( 3x10^4) spectrometer on the 1.3-m Araki telescope at Koyama Astronomical Observatory were carried out on UT 2013 November 30. The comet was at 0.91 AU from the Sun and 0.49 AU from the Earth at the observations. This comet was considered to originate in the Oort cloud and became bright in visible from October to December 2013. The newly developed instrument, WINERED, was a cross-dispersed Echelle spectrometer that can cover the wavelength range from 0.9 to 1.3 microns simultaneously. Many emission lines were recorded in the high signal-to-noise ratio spectra of comet Lovejoy. We report the line assignment of the detected emission lines and present our preliminary analysis for CN Red-band system.This research program is supported by the MEXT --- Supported Program for the Strategic Research Foundation at Private Universities, 2014 - 2018.

  15. HIGH-RESOLUTION MID-INFRARED SPECTROSCOPY OF NGC 7538 IRS 1: PROBING CHEMISTRY IN A MASSIVE YOUNG STELLAR OBJECT

    SciTech Connect

    Knez, Claudia; Lacy, John H.; Evans, Neal J.; Van Dishoeck, Ewine F.; Richter, Matthew J.

    2009-05-01

    We present high-resolution (R = 75,000-100,000) mid-infrared spectra of the high-mass embedded young star IRS 1 in the NGC 7538 star-forming region. Absorption lines from many rotational states of C{sub 2}H{sub 2}, {sup 13}C{sup 12}CH{sub 2}, CH{sub 3}, CH{sub 4}, NH{sub 3}, HCN, HNCO, and CS are seen. The gas temperature, column density, covering factor, line width, and Doppler shift for each molecule are derived. All molecules were fit with two velocity components between -54 and -63 km s{sup -1}. We find high column densities ({approx}10{sup 16} cm{sup -2}) for all the observed molecules compared to values previously reported and present new results for CH{sub 3} and HNCO. Several physical and chemical models are considered. The favored model involves a nearly edge-on disk around a massive star. Radiation from dust in the inner disk passes through the disk atmosphere, where large molecular column densities can produce the observed absorption line spectrum.

  16. High Resolution Spectroscopy in the Non-thermal Infrared: Use of an Existing Coude System

    NASA Astrophysics Data System (ADS)

    Basri, Gibor; Marcy, Geoffrey W.

    1993-05-01

    We describe a recent effort to use a NICMOS 3 chip as the detector on the 160" coude spectrograph camera at Lick Observatory. This new instrument (IRCS) has a useful spectral range of 1-2mu with spectral coverage in one exposure of about 25 Angstroms, and resolutions up to 75000. We have successfully obtained astronomical observations with essentially no modification of the (uncooled) spectrograph, using an existing grating blazed at 1.22mu , and a dewar without optics (but containing a filter) easily mounted at the position of the old photographic plates. The throughput of the system is very high. Its sensitivity is primarily limited by the background from the warm spectrograph. Using filters with 0.1mu bandwidth, the expected background is negligible below 1.5mu , but limits exposures to one minute near 2mu . With an optimized dewar, one can remain photon (rather than background) limited down to 10th magnitude even at 2mu . Our current system (using a test dewar and engineering grade chip) has been tested at 1.6mu . We have operated with and without an image slicer. We show spectra and discuss the current successes and problems. Our first application is to study the Zeeman--sensitive line at 1.56mu at high resolution. We expect to be able to achieve S/N of 200:1 in 10 minutes on 6th magnitude stars now, and eventually 100:1 in one hour on 10th magnitude stars using the 3-m telescope. This opens the possibility of measuring magnetic fields for large numbers of RS CVN and dM(e) stars (in addition to many G,K dwarfs), and even perhaps a few pre-main sequence stars. There is a lot of potential for science in the 1-2mu range at high resolution, which cannot be done as easily with any other type of instrument. This includes: (1) molecular lines in giants and winds, (2) lines from the ISM for abundances and kinematics, (3) detailed atmospheric analysis of embedded stars (and disks?).

  17. New Measurements of Doubly Ionized Iron Group Spectra by High Resolution Fourier Transform and Grating Spectroscopy

    NASA Technical Reports Server (NTRS)

    Smillie, D. G.; Pickering, J. C.; Blackwell-Whitehead, R. J.; Smith, Peter L.; Nave, G.

    2006-01-01

    We report new measurements of doubly ionized iron group element spectra, important in the analysis of B-type (hot) stars whose spectra they dominate. These measurements include Co III and Cr III taken with the Imperial College VUV Fourier transform (FT) spectrometer and measurements of Co III taken with the normal incidence vacuum spectrograph at NIST, below 135 nm. We report new Fe III grating spectra measurements to complement our FT spectra. Work towards transition wavelengths, energy levels and branching ratios (which, combined with lifetimes, produce oscillator strengths) for these ions is underway.

  18. A high-resolution extraterrestrial solar spectrum and water vapour continuum at near infrared wavelengths from ground-based spectrometer measurements

    NASA Astrophysics Data System (ADS)

    Menang, K. P.

    A high resolution extraterrestrial solar spectrum (CAVIAR solar spectrum) and water vapour continuum have been derived in near infrared windows from 2000-10000 cm-1 (105μm), by applying the Langley technique to calibrated ground-based high-resolution Fourier transform spectrometer measurements, made under clear-sky conditions. The effect of the choice of an extraterrestrial solar spectrum for radiative transfer calculations of clear-sky absorption and heating rates in the near infrared was also studied. There is a good agreement between the solar lines strengths and positions of the CAVIAR solar spectrum and those from both high-resolution satellite and ground-based measurements in their regions of spectral overlap. However, there are significant differences between the structure of the CAVIAR solar spectrum and spectra from models. Many of the detected lines are missing from widely-used modelled extraterrestrial solar spectrum. The absolute level and hence wavenumber-integrated solar irradiance of the CAVIAR solar spectrum was also found to be 8% lower than the satellite-based Thuillier et al spectra from 5200-10000 cm-1. Using different extraterrestrial solar spectra for radiative transfer calculations in the near infrared led to differences of up to about 11 W m-2 (8.2%) in the absorbed solar irradiance while the tropospheric and stratospheric heating rates could respectively differ by up to about 0.13K day-1 (8.1%) and 0.19 K day-1 (7.6%) for an overhead Sun and mid-latitude summer atmosphere. This work has shown that the widely-used empirically modelled continuum may be underestimating the strength of the water vapour continuum from 2000-10000 cm-1, with the derived continuum up to more than 2 orders of magnitude stronger at some wavenumbers in the windows. The derived continuum is also stronger than that implied by laboratory measurements, by a factor of up to 40 in some spectral regions.

  19. High resolution hard X-ray spectra of solar and cosmic sources. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Schwartz, R. A.

    1984-01-01

    High resolution hard X-ray observations of a large solar flare and the Crab Nebula were obtained during balloon flights using an array of cooled germanium planar detectors. In addition, high time resolution high sensitivity measurements were obtained with a 300 square cm NaI/CsI phoswich scintillator. The Crab spectrum from both flights was searched without finding evidence of line emission below 200 keV. In particular, for the 73 keV line previously reported a 3 sigma upper limit for a narrow (1 keV FWHM) line .0019 and .0014 ph square cm/sec for the 1979 and 1980 flights, respectively was obtained.

  20. Analysis of high-resolution spectra from a hybrid interferometric/dispersive spectrometer

    SciTech Connect

    Ko, Phyllis; Scott, Jill R.; Jovanovic, Igor

    2015-09-05

    To fully take advantage of a low-cost, small footprint hybrid interferometric/dispersive spectrometer, a math- ematical reconstruction technique was developed to accurately capture the high-resolution and relative peak intensities from complex patterns. A Fabry-Perot etalon was coupled to a Czerny-Turner spectrometer, in- creasing spectral resolution by an order of magnitude without the commensurate increase in spectrometer size. Measurement of the industry standard Hg 313.1555/313.1844 nm doublet yielded a ratio of 0.682 with 1.8%error, which agreed well with an independent measurement and literature values. The doublet separation (29 pm), is similar to the U isotope shift (25 pm) at 424.437 nm that is of interest to monitoring nuclear nonpro-liferation activities. Additionally, the technique was applied to a LIBS measurement of the mineral cinnabar (HgS) and resulted in a ratio of 0.681. In addition, this reconstruction method could enable significantly smaller, portable high-resolution instruments with isotopic specificity, benefiting a variety of spectroscopic applications.

  1. Analysis of high-resolution spectra from a hybrid interferometric/dispersive spectrometer

    DOE PAGESBeta

    Ko, Phyllis; Scott, Jill R.; Jovanovic, Igor

    2015-09-05

    To fully take advantage of a low-cost, small footprint hybrid interferometric/dispersive spectrometer, a math- ematical reconstruction technique was developed to accurately capture the high-resolution and relative peak intensities from complex patterns. A Fabry-Perot etalon was coupled to a Czerny-Turner spectrometer, in- creasing spectral resolution by an order of magnitude without the commensurate increase in spectrometer size. Measurement of the industry standard Hg 313.1555/313.1844 nm doublet yielded a ratio of 0.682 with 1.8%error, which agreed well with an independent measurement and literature values. The doublet separation (29 pm), is similar to the U isotope shift (25 pm) at 424.437 nm thatmore » is of interest to monitoring nuclear nonpro-liferation activities. Additionally, the technique was applied to a LIBS measurement of the mineral cinnabar (HgS) and resulted in a ratio of 0.681. In addition, this reconstruction method could enable significantly smaller, portable high-resolution instruments with isotopic specificity, benefiting a variety of spectroscopic applications.« less

  2. Analysis of high-resolution spectra from a hybrid interferometric/dispersive spectrometer

    NASA Astrophysics Data System (ADS)

    Ko, Phyllis; Scott, Jill R.; Jovanovic, Igor

    2015-12-01

    To more fully take advantage of a low-cost, small footprint hybrid interferometric/dispersive spectrometer, a mathematical reconstruction technique was developed to accurately capture the high-resolution and relative peak intensities from complex spectral patterns. A Fabry-Perot etalon was coupled to a Czerny-Turner spectrometer, leading to increased spectral resolution by more than an order of magnitude without the commensurate increase in spectrometer size. Measurement of the industry standard Hg 313.1555/313.1844 nm doublet yielded a ratio of 0.682, which agreed well with an independent measurement and literature values. The doublet separation (29 pm) is similar to the U isotope shift (25 pm) at 424.437 nm that is of interest to monitoring nuclear nonproliferation activities. Additionally, the technique was applied to LIBS measurement of the mineral cinnabar (HgS) and resulted in a ratio of 0.682. This reconstruction method could enable significantly smaller, portable high-resolution instruments with isotopic specificity, benefiting a variety of spectroscopic applications.

  3. Analysis of high-resolution spectra from a hybrid interferometric/dispersive spectrometer

    SciTech Connect

    Ko, Phyllis; Scott, Jill R.; Jovanovic, Igor

    2015-09-05

    To fully take advantage of a low-cost, small footprint hybrid interferometric/dispersive spectrometer, a math- ematical reconstruction technique was developed to accurately capture the high-resolution and relative peak intensities from complex patterns. A Fabry-Perot etalon was coupled to a Czerny-Turner spectrometer, in- creasing spectral resolution by an order of magnitude without the commensurate increase in spectrometer size. Measurement of the industry standard Hg 313.1555/313.1844 nm doublet yielded a ratio of 0.682 with 1.8%error, which agreed well with an independent measurement and literature values. The doublet separation (29 pm), is similar to the U isotope shift (25 pm) at 424.437 nm that is of interest to monitoring nuclear nonpro-liferation activities. Additionally, the technique was applied to a LIBS measurement of the mineral cinnabar (HgS) and resulted in a ratio of 0.681. This reconstruction method could enable significantly smaller, portable high-resolution instruments with isotopic specificity, benefiting a variety of spectroscopic applications.

  4. Analysis of several high-resolution infrared bands of spiropentane, C5H8

    SciTech Connect

    Maki, Arthur G.; Price, Joseph E.; Harzan, J.; Nibler, Joseph W.; Weber, Alfons; Masiello, Tony; Blake, Thomas A.

    2015-06-01

    he high-resolution infrared absorption spectrum of spiropentane (C5H8) has been measured from 200 to 4000 cm 1, and a detailed analysis is presented for eight bands in the region from 700 to 2200 cm 1. Two fundamental perpendicular bands were analyzed, m22 and m24 near 1050 and 780 cm 1, respectively, along with two fundamental parallel bands, m14 and m16 near 1540 and 990 cm1, respectively. Two other fundamentals, m17 and m23, are seen as intense overlapping bands near 880 cm*1 and are Coriolis-coupled, producing a complex mixture in which only P-branch transitions could be tentatively assigned for m17. In addition, three binary combination bands were fit at about 1570, 2082, and 2098 cm*1 which are assigned as either 2m24 or m5 + m16 in the first case, m4 + m22 in the second case, and 2m22 in the latter case. The two l-type resonance constants, q+ and q*, were determined for each of the two perpendicular fundamentals m22 and m24. Those two constants were also responsible for splittings observed in the K = 3 levels of m24. For the ground state the order of the split K = 2 B1/B2 levels has been reversed from that reported previously, based on the measurements and assignments for the m24 band. Rovibrational parameters deduced from the analyses are compared with those obtained from density functional Gaussian calculations at the anharmonic level.

  5. High Resolution Far Infrared Fourier Transform Spectroscopy of the NH_2 Radical.

    NASA Astrophysics Data System (ADS)

    Martin-Drumel, M. A.; Pirali, O.; Balcon, D.; Vervloet, M.

    2011-06-01

    First identified toward Sgr B2, the NH_2 radical has recently been detected in the interstellar medium by the HIFI instrument on board of Herschel. Despite the fact that this radical has not been detected in brown dwarfs and exoplanets yet, it is already included in physical and chemical models of those environments (temperature higher than 2000 K expected in several objects). Its detection in those objects will depend on the existence of a reliable high temperature and high resolution spectroscopic database on the NH_2 radical.The absorption spectrum of NH_2 has been recorded between 15 and 700 Cm-1 at the highest resolution available using the Bruker IFS125HR Fourier transform interferometer connected to the far infrared AILES beamline at SOLEIL (R=0.001 Cm-1). The radical was produced by an electrical discharge (DC) through a continuous flow of NH_3 and He using the White-type discharge cell developped on the beamline (optical path: 24m). Thanks to the brilliance of the synchrotron radiation, more than 700 pure rotational transitions of NH_2 have been identified with high N values (NMax=25) in its fundamental and first excited vibrational modes. By comparison to the previous FT spectroscopic study on that radical in the FIR spectral range, asymmetric splitting as well as fine and hyperfine structure have been resolved for several transitions. E. F. Van Dishoeck, D. J. Jansen, P. Schilke, T. G. Phillips The Astrophysical Journal 416, L83-L86 (1993) C. M. Persson, J. H. Black, J. Cernicharo et al. Astronomy and Astrophysics 521, L45 (2010) K. Lodders and B. Fegley, Jr Icarus 155, 393-424 (2002) I. Morino and K. Kawaguchi Journal of Molecular Spectroscopy 182, 428-438 (1997)

  6. Coriolis analysis of several high-resolution infrared bands of bicyclo[111]pentane-d0 and -d1

    SciTech Connect

    Perry, A.; Martin, M. A.; Nibler, J. W.; Maki, A.; Weber, A.; Blake, T. A.

    2012-06-01

    High resolution infrared absorption spectra have been analyzed for two bicyclo[1.1.1]pentane isotopologues, C5H8 (-d0) and C5H7D (-d1), where in the latter the D-atom replaces a hydrogen on the C3 symmetry axis such that the molecular symmetry is reduced from D3h to C3v. Two (a2") parallel bands, ν17 and ν18, of bicyclopentane-d0 were studied and the former was found to be profoundly affected by Coriolis coupling with the nearby (e') perpendicular band, ν11. Weaker coupling was observed between the ν18 band and the nearby ν13(e') band, for which fewer transitions could be assigned. For bicyclopentane-d1, the ν5 parallel band was also studied along with the nearby ν15(e') band to which it is coupled through a similar type of Coriolis resonance. For both isotopologues, quantum calculations (B3LYP/cc-pVTZ) done at the anharmonic level were very helpful in unraveling the complexities caused by the Coriolis interactions, provided that care is taken in identifying the effect of any Coriolis resonances in the theoretical values of aB and q rovibrational parameters. The ground state B0 constants were found to be 0.2399412(2) and 0.2267506(11) cm-1 for the -d0 and -d1 isotopologues. The difference yields an Rs substitution value of 2.0309(2) Å for the position of the axial H atom relative to the -d0 center of mass, a result in good accord with a corresponding Ra value of 2.044(6) Å from electron diffraction data. For both isotopologues, the theoretical results from the quantum calculations are in good agreement with all corresponding values determined from the spectra.

  7. On-chip near-infrared spectroscopy of CO2 using high resolution plasmonic filter array

    NASA Astrophysics Data System (ADS)

    Chong, Xinyuan; Li, Erwen; Squire, Kenneth; Wang, Alan X.

    2016-05-01

    We report an ultra-compact, cost-effective on-chip near-infrared spectroscopy system for CO2 sensing using narrow-band optical filter array based on plasmonic gratings with a waveguide layer. By varying the periodicity of the gratings, the transmission spectra of the filters can be continuously tuned to cover the 2.0 μm sensing window with high spectral resolution around 10 nm. Our experimental results show that the on-chip spectroscopy system can resolve the two symmetric vibrational bands of CO2 at 2.0 μm wavelength, which proves its potential to replace the expensive commercial IR spectroscopy system for on-site gas sensing.

  8. High-Resolution Observations of the Infrared Spectrum of Neutral Neon

    PubMed Central

    Sansonetti, Craig J.; Blackwell, Marion M.; Saloman, E. B.

    2004-01-01

    We have observed the spectrum of neutral neon (Ne I) emitted by a microwave-excited electrodeless discharge lamp with the National Institute of Standards and Technology 2 m Fourier transform spectrometer. The spectra cover the regions 6929 Å to 11 000 Å with a resolution of 0.01 cm−1 and 11 000 Å to 47 589 Å with a resolution of 0.007 cm−1. We present a line list that includes more than 650 classified lines and provides an accurate and comprehensive description of the infrared spectrum. The response of the Fourier transform spectrometer was determined by using a radiometrically calibrated tungsten strip lamp, providing relative intensities that for moderate to strong lines are accurate to approximately 10 % over the entire range of the observations. The identities of many lines that were previously multiply classified are unambiguously resolved. PMID:27366619

  9. Chemical Analysis of Exhaled Human Breath Using High Resolution Mm-Wave Rotational Spectra

    NASA Astrophysics Data System (ADS)

    Guo, Tianle; Branco, Daniela; Thomas, Jessica; Medvedev, Ivan; Dolson, David; Nam, Hyun-Joo; O, Kenneth

    2014-06-01

    High resolution rotational spectroscopy enables chemical sensors that are both sensitive and highly specific, which is well suited for analysis of expired human breath. We have previously reported on detection of breath ethanol, methanol, acetone, and acetaldehyde using THz sensors. This paper will outline our present efforts in this area, with specific focus on our ongoing quest to correlate levels of blood glucose with concentrations of a few breath chemicals known to be affected by elevated blood sugar levels. Prospects, challenges and future plans will be outlined and discussed. Fosnight, A.M., B.L. Moran, and I.R. Medvedev, Chemical analysis of exhaled human breath using a terahertz spectroscopic approach. Applied Physics Letters, 2013. 103(13): p. 133703-5.

  10. The deep atmosphere of Venus revealed by high-resolution nightside spectra

    NASA Technical Reports Server (NTRS)

    Bezard, Bruno; De Bergh, Catherine; Crisp, David; Maillard, Jean-Pierre

    1990-01-01

    The first high-resolution spectroscopic observations of the night side of Venus obtained in two narrow spectral windows centered at 1.74 and 2.3 microns, where the nightside is anomalously bright, are reported. Absorption features from CO2, CO, H2O, HDO, HCl, HF, and COS are detected, and there are a number of unidentified features. A preliminary analysis indicates that the observed radiation is thermal emission from atmospheric layers in the eight-bar pressure region for the 2.3 micron window and even deeper at 1.7 micron. The derived CO and H2O abundances agree with in situ Pioneer measurements in the deep troposphere and are consistent with the high deuterium enrichment inferred from Pioneer data. The first measurements of HCl and HF below the clouds are reported along with the first firm detection of COS.

  11. Measurement of magnetic field aligned potential differences using high resolution conjugate photoelectron energy spectra

    NASA Technical Reports Server (NTRS)

    Peterson, W. K.; Doering, J. P.; Potemra, T. A.; Bostrom, C. O.; Brace, L. H.; Heelis, R. A.; Hanson, W. B.

    1977-01-01

    Simultaneous high-resolution observations of a distinctive feature in the energy spectrum of conjugate photoelectrons and spacecraft potential relative to the local ionosphere have allowed the net potential difference between magnetic conjugate points at latitudes below the region of low-energy (i.e., lower than 100 eV) auroral electron precipitation to be determined. Measurements made at 300 km from Atmosphere Explorer C show that there is normally no net potential difference between hemispheres in this region, which extended up to invariant latitudes as high as 74 deg. Two types of apparently related anomalous behavior were infrequently observed at high latitudes. During these periods the incident flux of conjugate photoelectrons was either decelerated by about 3 eV or was not detected.

  12. A high-resolution atlas of composite Sloan Digital Sky Survey galaxy spectra

    NASA Astrophysics Data System (ADS)

    Dobos, László; Csabai, István.; Yip, Ching-Wa; Budavári, Tamás.; Wild, Vivienne; Szalay, Alexander S.

    2012-02-01

    In this work we present an atlas of composite spectra of galaxies based on the data of the Sloan Digital Sky Survey Data Release 7 (SDSS DR7). Galaxies are classified by colour, nuclear activity and star formation activity to calculate average spectra of high signal-to-noise ratio (S/N) and resolution (? at Δλ= 1 Å), using an algorithm that is robust against outliers. Besides composite spectra, we also compute the first five principal components of the distributions in each galaxy class to characterize the nature of variations of individual spectra around the averages. The continua of the composite spectra are fitted with BC03 stellar population synthesis models to extend the wavelength coverage beyond the coverage of the SDSS spectrographs. Common derived parameters of the composites are also calculated: integrated colours in the most popular filter systems, line-strength measurements and continuum absorption indices (including Lick indices). These derived parameters are compared with the distributions of parameters of individual galaxies, and it is shown on many examples that the composites of the atlas cover much of the parameter space spanned by SDSS galaxies. By co-adding thousands of spectra, a total integration time of several months can be reached, which results in extremely low noise composites. The variations in redshift not only allow for extending the spectral coverage bluewards to the original wavelength limit of the SDSS spectrographs, but also make higher spectral resolution achievable. The composite spectrum atlas is available online at .

  13. Leveraging High Resolution Spectra to Understand the Disk and Relativistic Iron Line of Cygnus X-1

    NASA Astrophysics Data System (ADS)

    Nowak, M.; Wilms, J.; Pottschmidt, K.; Grinberg, V.; Schulz, N.; Corrales, L.

    2016-06-01

    In April 2008 we conducted an observation of the black hole candidate Cygnus X-1 that was performed simultaneously with every X-ray and gamma-ray satellite flying at that time, including Chandra-HETG. The HETG spectra are crucial for modeling the ionized absorbtion from the "focused-wind" of the secondary, which is present and must be accounted for in all of our spectra. These features, however, are unresolved in the non-gratings instruments (e.g., RXTE, Suzaku, Swift, XMM-EPIC, INTEGRAL). Similarly, we must account for differences in spatial resolution. The X-ray scattering dust halo, which is usually ignored in most analyses, is spatially resolved in the Chandra and XMM-Newton spectra, but is unresolved in the other instruments. Thus one must account for dust scattering loss in the high spatial resolution spectra, and the scattering back into our line of site for the low resolution spectra. In this work, we attempt to arrive at a joint model for these spectra, and further comment on the cross calibration of each of the X-ray instruments participating in this campaign.

  14. Simulation of High Resolution Vibrational and Electronic Spectra with a Multifrequency Virtual Spectrometer

    NASA Astrophysics Data System (ADS)

    Biczysko, Malgorzata; Bloino, Julien; Barone, Vincenzo

    2013-06-01

    Moving from the common practice of extracting numerical data from experiment to be compared with quantum mechanical (QM) results toward a direct vis-à-vis} comparison of experimental and simulated spectra would strongly reduce any arbitrariness in analysis of complex experimental outcomes and allow a proper account of the information connected to both position and shape of spectral bands. The development of such ``virtual ab initio spectrometers'' for a wide range of wavelengths has been one of our major research goals in the last years [1,2]. Recent methodological advances from our group allow simulation of optical (IR, Raman, UV-vis, etc.) spectra line-shapes for medium-to-large closed- and open-shell molecular systems. Vibrational spectra are computed including anharmonicities through perturbative corrections while electronic spectra line-shapes are simulated accounting for the vibrational structure. Well resolved and accurate theoretical spectra provide data as close as possible to the results directly available from experiment allowing to avoid ambiguities in analysis of the latter. Several examples illustrating interpretation, assignment or revision of experimental spectra for prototypes of bio-molecular systems (phenyl radical, glycine, thymine, pyrimidine, anisole dimer) will be presented. 1. V. Barone, A. Baiardi, M. Biczysko, J. Bloino, C. Cappelli, F. Lipparini Phys. Chem. Chem. Phys, 14, 12404, 2012 2. M. Biczysko, J. Bloino, G. Brancato, et al. Theor. Chem. Acc. 113, 1201, 2012

  15. High resolution spectroscopy of six SOCl2 isotopologues from the microwave to the far-infrared

    NASA Astrophysics Data System (ADS)

    Martin-Drumel, M. A.; Roucou, A.; Brown, G. G.; Thorwirth, S.; Pirali, O.; Mouret, G.; Hindle, F.; McCarthy, M. C.; Cuisset, A.

    2016-02-01

    Despite its potential role as an atmospheric pollutant, thionyl chloride, SOCl2, remains poorly characterized in the gas phase. In this study, the pure rotational and ro-vibrational spectra of six isotopologues of this molecule, all detected in natural abundance, have been extensively studied from the cm-wave band to the far-infrared region by means of three complementary techniques: chirped-pulse Fourier transform microwave spectroscopy, sub-millimeter-wave spectroscopy using frequency multiplier chain, and synchrotron-based far-infrared spectroscopy. Owing to the complex line pattern which results from two nuclei with non-zero spins, new, high-level quantum-chemical calculations of the hyperfine structure played a crucial role in the spectroscopic analysis. From the combined experimental and theoretical work, an accurate semi-experimental equilibrium structure (reSE) of SOCl2 has been derived. With the present data, spectroscopy-based methods can now be applied with confidence to detect and monitor this species, either by remote sensing or in situ.

  16. Stellar parameters of M dwarfs from low and high-resolution spectra together with new model atmospheres

    NASA Astrophysics Data System (ADS)

    Rajpurohit, A. S.; Reylé, C.; Schultheis, M.; Allard, F.; Scholz, R.; Homeier, D.

    2012-12-01

    We present an optical spectral atlas of stars covering the whole M-dwarf sequence. It consists of 95 M dwarfs at solar metallicity observed at low-resolution with EMMI@NTT and 21 M-subdwarfs, extreme-subdwarfs and ultra-subdwarfs observed at high resolution with UVES@VLT. Using the most recent PHOENIX BT-Settl stellar model atmospheres we perform a detailed comparison with our observed spectra using χ^2 minimization technique. We confront the models with low-resolution spectra of M dwarfs at solar metallicity and we assign effective temperatures to the M dwarfs. We present temperature versus spectral type and colour relations and their comparison with others found in the literature. We also present our high-resolution spectra of the subdwarfs (sdM, esdM, usdM) and compare them to the newest grid of the BT Settl models which uses the revised solar abundances of Caffau et al (2011). This comparison allows us to study the spectral details of cool atmospheres, to determine precise [Fe/H] values for our objects, and to investigate the effect of metallicity on cool dwarf atmospheres. This study also helps to validate the atmosphere models and improve them by determining new constants on molecular opacities, dust cloud formation etc.

  17. Application of the Lucy–Richardson Deconvolution Procedure to High Resolution Photoemission Spectra

    SciTech Connect

    Rameau, J.; Yang, H.-B.; Johnson, P.D.

    2010-07-01

    Angle-resolved photoemission has developed into one of the leading probes of the electronic structure and associated dynamics of condensed matter systems. As with any experimental technique the ability to resolve features in the spectra is ultimately limited by the resolution of the instrumentation used in the measurement. Previously developed for sharpening astronomical images, the Lucy-Richardson deconvolution technique proves to be a useful tool for improving the photoemission spectra obtained in modern hemispherical electron spectrometers where the photoelectron spectrum is displayed as a 2D image in energy and momentum space.

  18. High resolution infrared ``vision'' of dynamic electron processes in semiconductor devices (abstract)

    NASA Astrophysics Data System (ADS)

    Malyutenko, V. K.

    2003-01-01

    Infrared cameras have been traditionally used in semiconductor industry for noncontact measurements of printed circuit boards (PCBs) local overheating. While an effective way to prevent defective PCB application in a "find-problems-before-your-customer-do" manner, this conventional static (25-50 frames/s) and small spatial resolution (>100 μm) approach is incapable, in principle, of explaining the physical reason for the PCB failure. What follows in this report is the demonstration of an IR camera based new approach in high-resolution dynamic study of electron processes responsible for single device performance. More specifically, time resolved two-dimensional visualization of current carrier drift and diffusion processes across the device base that happen in microsecond scale is of prime concern in the work. Thus, contrary to the conventional visualization-through-heating measurements, objective is mapping of electron processes in a device base through negative and positive luminescence (provoked by band-to-band electron transitions) and nonequilibrium thermal emission (provoked by intraband electron transitions) studies inside the region in which current flows. Therefore, the parameters of interest are not only a device thermal mass and thermal conductance, but also free carrier lifetime, surface recombination velocity, diffusion length, and contact properties. The micro-mapping system developed consists of reflective type IR microscope coaxially attached to calibrated scanning IR thermal imaging cameras (3-5 and 8-12 μm spectral ranges, HgCdTe cooled photodetectors, scene spatial resolution of some 20 μm, minimum time resolved interval of 10 μs, and temperature resolution of about 0.5 °C at 30 °C). Data acquisition and image processing (emissivity equalization, noise reduction by image averaging, and external triggering) are computer controlled. Parallel video channel equipped with a CCD camera permits easy positioning and focusing of <1×1 mm2 object

  19. High-Resolution Infrared Spectroscopic Measurements of Comet 2PlEncke: Unusual Organic Composition and Low Rotational Temperatures

    NASA Technical Reports Server (NTRS)

    Radeva, Yana L.; Mumma, Michael J.; Villanueva, Geronimo L.; Bonev, Boncho P.; DiSanti, Michael A.; A'Hearn, Michael F.; Dello Russo, Neil

    2013-01-01

    We present high-resolution infrared spectroscopic measurements of the ecliptic comet 2P/Encke, observed on 4-6 Nov. 2003 during its close approach to the Earth, using the Near Infrared Echelle Spectrograph on the Keck II telescope. We present flux-calibrated spectra, production rates, and mixing ratios for H2O, CH3OH, HCN, H2CO, C2H2, C2H6, CH4 and CO. Comet 2P/Encke is a dynamical end-member among comets because of its short period of 3.3 years. Relative to "organics-normal" comets, we determined that 2PlEncke is depleted in HCN, H2CO, C2H2, C2H6, CH4 and CO, but it is enriched in CH3OH. We compared mixing ratios of these organic species measured on separate dates, and we see no evidence of macroscopic chemical heterogeneity in the nucleus of 2P/Encke, however, this conclusion is limited by sparse temporal sampling. The depleted abundances of most measured species suggest that 2P/Encke may have formed closer to the young Sun, before its insertion to the Kuiper belt, compared with "organics-normal" comets - as was previously suggested for other depleted comets (e.g. C/1999 S4 (LINEAR)). We measured very low rotational temperatures of 20 - 30 K for H2O, CH3OH and HCN in the near nucleus region of 2P/Encke, which correlate with one of the lowest cometary gas production rates (approx. 2.6 x 10(exp 27) molecules/s) measured thus far in the infrared. This suggests that we are seeing the effects of more efficient radiative cooling, insufficient collisional excitation, and/or inefficient heating by fast H-atoms (and icy grains) in the observed region of the coma. Its extremely short orbital period, very low gas production rate, and classification as an ecliptic comet, make 2PlEncke an important addition to our growing database, and contribute significantly to the establishment of a chemical taxonomy of comets.

  20. Quantitative Infrared Spectra of Vapor Phase Chemical Agents

    SciTech Connect

    Sharpe, Steven W.; Johnson, Timothy J.; Chu, P. M.; Kleimeyer, J.; Rowland, Brad

    2003-08-01

    Quantitative, moderately high resolution (0.1 cm-1) infrared spectra have been acquired for a number of nitrogen broadened (1 atm N2) vapor phase chemicals including: Sarin (GB), Soman (GD), Tabun (GA), Cyclosarin (GF), VX, Nitrogen Mustard (HN3), Sulfur Mustard (HD), and Lewisite (L). The spectra are acquired using a heated, flow-through White Cell1 of 5.6 meter optical path length. Each reported spectrum represents a statistical fit to Beer’s law, which allows for a rigorous calculation of uncertainty in the absorption coefficients. As part of an ongoing collaboration with the National Institute of Standards and Technology (NIST), cross-laboratory validation is a critical aspect of this work. In order to identify possible errors in the Dugway flow-through system, quantitative spectra of isopropyl alcohol from both NIST and Pacific Northwest National Laboratory (PNNL) are compared to similar data taken at Dugway proving Grounds (DPG).

  1. Rapid probe of the nicotine spectra by high-resolution rotational spectroscopy.

    PubMed

    Grabow, Jens-Uwe; Mata, S; Alonso, José L; Peña, I; Blanco, S; López, Juan C; Cabezas, C

    2011-12-21

    Nicotine has been investigated in the gas phase and two conformational forms were characterized through their rotational spectra. Two spectroscopic techniques have been used to obtain the spectra: a new design of broadband Fourier transform microwave (FTMW) spectroscopy with an in-phase/quadrature-phase-modulation passage-acquired-coherence technique (IMPACT) and narrowband FTMW spectroscopy with coaxially oriented beam-resonator arrangement (COBRA). The rotational, centrifugal distortion and hyperfine quadrupole coupling constants of two conformers of nicotine have been determined and found to be in N-methyl trans configurations with the pyridine and pyrrolidine rings perpendicular to one another. The quadrupole hyperfine structure originated by two (14)N nuclei has been completely resolved for both conformers and used for their unambiguous identification. PMID:22020263

  2. High-resolution J-resolved NMR spectra of dilute spins in solids

    NASA Astrophysics Data System (ADS)

    Terao, T.; Miura, H.; Saika, A.

    1981-08-01

    A technique for obtaining J-resolved NMR spectra of dilute spins in solids has been developed. It is based on the observation that a combination of magic-angle irradiation and magic-angle spinning removes dipolar broadening, but leaves indirect spin-spin coupling. A preliminary application of this technique to adamantane clearly reveals the AX (J = 121 Hz) and AX (J = 135 Hz) multiplets in the methylene and methyne 13C spectrum, respectively.

  3. High resolution infrared spectroscopy from space: A preliminary report on the results of the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment on Spacelab 3

    NASA Technical Reports Server (NTRS)

    Farmer, Crofton B.; Raper, Odell F.

    1987-01-01

    The ATMOS (Atmospheric Trace Molecule Spectroscopy) experiment has the broad purpose of investigating the physical structure, chemistry, and dynamics of the upper atmosphere through the study of the distributions of the neutral minor and trace constituents and their seasonal and long-term variations. The technique used is high-resolution infrared absorption spectroscopy using the Sun as the radiation source, observing the changes in the transmission of the atmosphere as the line-of-sight from the Sun to the spacecraft penetrates the atmosphere close to the Earth's limb at sunrise and sunset. During these periods, interferograms are generated at the rate of one each second which yield, when transformed, high resolution spectra covering the 2.2 to 16 micron region of the infrared. Twenty such occultations were recorded during the Spacelab 3 flight, which have produced concentration profiles for a large number of minor and trace upper atmospheric species in both the Northern and Southern Hemispheres. Several of these species have not previously been observed in spectroscopic data. The data reduction and analysis procedures used following the flight are discussed; a number of examples of the spectra obtained are shown, and a bar graph of the species detected thus far in the analysis is given which shows the altitude ranges for which concentration profiles were retrieved.

  4. TSAR: a program for automatic resonance assignment using 2D cross-sections of high dimensionality, high-resolution spectra.

    PubMed

    Zawadzka-Kazimierczuk, Anna; Koźmiński, Wiktor; Billeter, Martin

    2012-09-01

    While NMR studies of proteins typically aim at structure, dynamics or interactions, resonance assignments represent in almost all cases the initial step of the analysis. With increasing complexity of the NMR spectra, for example due to decreasing extent of ordered structure, this task often becomes both difficult and time-consuming, and the recording of high-dimensional data with high-resolution may be essential. Random sampling of the evolution time space, combined with sparse multidimensional Fourier transform (SMFT), allows for efficient recording of very high dimensional spectra (≥4 dimensions) while maintaining high resolution. However, the nature of this data demands for automation of the assignment process. Here we present the program TSAR (Tool for SMFT-based Assignment of Resonances), which exploits all advantages of SMFT input. Moreover, its flexibility allows to process data from any type of experiments that provide sequential connectivities. The algorithm was tested on several protein samples, including a disordered 81-residue fragment of the δ subunit of RNA polymerase from Bacillus subtilis containing various repetitive sequences. For our test examples, TSAR achieves a high percentage of assigned residues without any erroneous assignments. PMID:22806130

  5. Wavelength calibration of spectra measured by the Global Ozone Monitoring Experiment by use of a high-resolution reference spectrum.

    PubMed

    van Geffen, Jos H G M; van Oss, Roeland F

    2003-05-20

    Earthshine spectra measured by the nadir-viewing Global Ozone Monitoring Experiment (GOME) spectrometer aboard the second European Remote Sensing (ERS-2) Satellite in the range of 240-790 nm are widely used for the retrieval of concentrations and vertical profiles of atmospheric trace gases. For the near-real-time delivery of ozone columns and profiles at the Royal Netherlands Meterological Institute, a tailor-made wavelength calibration method was developed. The method use a high-resolution (0.01-nm) solar spectrum as the reference spectrum and applies both a shift and a squeeze to the wavelengths in selected windows to find the optimal wavelength grid per window. This method provides a calibration accuracy of 0.002 nm below and 0.001 nm above 290 nm. The new wavelength calibration method can be used on any wavelength window, for example, to improve the calibration of spectra from the GOME Data Processor. A software package, GomeCal, which performs this recalibration, along with an improved polarization and radiometric correction, has been made and has been released via the World Wide Web. The method can be used for any high-resolution (ir)radiance spectrometer, such as the satellite instruments SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Cartography), Ozone Monitoring Instrument, and GOME-2. PMID:12777012

  6. High resolution infrared spectrum of the CD2 wagging band of methanol-D2 (CHD2OH) for the lowest lying torsional vibrational state (e0)

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Indra

    2016-07-01

    This paper reports the analysis of the high resolution (0.0019 cm-1) Fourier transform infrared (FTIR) spectrum for asymmetrically deuterated methanol CHD2OH (methanol-D2) at a low temperature for the CD2 wagging band for the lowest lying trans-species (e0). In spite of the complexity and perturbation in the spectra, assignments were possible for the CD2 wagging band for a maximum K value of 10. In total, about 500 spectral lines have been assigned. Analysis of the spectral lines has been performed in terms of state dependent molecular parameters, Q-branch origins and asymmetry splitting. Assignments have been thoroughly confirmed using combination relations (see text). The catalogue of the assigned transition wavenumbers will help identification and prediction of far infrared (FIR) optically pumped CO2 lasers. The absorption lines close to the several 10R and 10P CO2 laser lines have also been identified. These should help experimentalists to optimize the power of the emission FIR laser lines and to predict new lines and should prove valuable as a laboratory support for interstellar detection in "Radio Astronomy". To our knowledge this is the first time such vibrational infrared (IR) high resolution study in CHD2OH is being performed.

  7. Deriving chlorophyll fluorescence emissions of vegetation canopies from high resolution field reflectance spectra

    NASA Astrophysics Data System (ADS)

    Middleton, Elizabeth M.; Corp, Lawrence A.; Daughtry, Craig S.; Entcheva Campbell, Petya K.; Butcher, L. Maryn

    2005-11-01

    Fluorescence of foliage in the laboratory has proven more rigorous than reflectance for correlation to plant physiology. Especially useful are emissions produced from two stable red and far-red chlorophyll fluorescence (ChlF) peaks centered at 685 nm and 735 nm. Methods have been developed elsewhere to extract steady state solar induced fluorescence (SIF) from apparent reflectance of vegetation canopies/landscapes using the Fraunhofer Line Depth (FLD) principal. Our study utilized these methods in conjunction with field-acquired high spectral resolution canopy reflectance spectra obtained in 2004 and 2005 over corn crops and small tree plots of three deciduous species (red maple, tulip poplar, sweet gum). Leaf level measurements were also made of foliage which included ChlF, photosynthesis, and leaf constituents (photosynthetic pigment, carbon (C), and nitrogen (N) contents). As part of ongoing experiments, measurements were made on N application plots within corn (280, 140, 70, and 0 kg N/ha) and tree (0, 37.5, 75, 112.5, 150 kg N /ha) sites at the USDA/Agriculture Research Service in Beltsville, MD. SIF intensities for ChlF were derived directly from canopy reflectance spectra in specific narrow- band regions associated with atmospheric oxygen absorption features centered at 688 and 760 nm. The red/far-red SIF ratio (SIFratio) derived from these field reflectance spectra successfully discriminated foliar pigment ratios altered by N application rates in both corn crops. This ratio was also positively correlated to the C/N ratio at leaf and canopy levels, for the available corn data (e.g., 2004). No consistent N treatment or species differences in SIF were detected in the tree foliage, but additional 2005 data are forthcoming. This study has relevance to future passive satellite remote sensing approaches to monitoring C dynamics from space.

  8. High-resolution emission spectra of pulsed terahertz quantum-cascade lasers

    SciTech Connect

    Ikonnikov, A. V. Antonov, A. V.; Lastovkin, A. A.; Gavrilenko, V. I.; Sadof'ev, Yu. G.; Samal, N.

    2010-11-15

    The spectra of pulsed terahertz quantum-cascade lasers were measured with high spectral resolution. The characteristic line width at half maximum was 0.01 cm{sup -1}; it is controlled by laser temperature variations during the supply voltage pulse. It was shown that an increase in the laser temperature leads to a decrease in the emission frequency, which is caused by an increase in the effective refractive index of the active region. It was also found that a decrease in the supply voltage results in a decrease in the emission frequency, which is caused by a change in the energy of diagonal transitions between lasing levels.

  9. Chlorophyll Fluorescence Emissions of Vegetation Canopies From High Resolution Field Reflectance Spectra

    NASA Technical Reports Server (NTRS)

    Middleton, E. M.; Corp, L. A.; Daughtry, C. S. T.; Campbell, P. K. Entcheva

    2006-01-01

    A two-year experiment was performed on corn (Zea mays L.) crops under nitrogen (N) fertilization regimes to examine the use of hyperspectral canopy reflectance information for estimating chlorophyll fluorescence (ChlF) and vegetation production. Fluorescence of foliage in the laboratory has proven more rigorous than reflectance for correlation to plant physiology. Especially useful are emissions produced from two stable red and far-red chlorophyll ChlF peaks centered at 685V10 nm and 735V5 nm. Methods have been developed elsewhere to extract steady state solar induced fluorescence (SF) from apparent reflectance of vegetation canopies/landscapes using the Fraunhofer Line Depth (FLD) principal. Our study utilized these methods in conjunction with field-acquired high spectral resolution canopy reflectance spectra obtained in 2004 and 2005 over corn crops, as part of an ongoing multi-year experiment at the USDA/Agriculture Research Service in Beltsville, MD. A spectroradiometer (ASD-FR Fieldspec Pro, Analytical Spectral Devices, Inc., Boulder, CO) was used to measure canopy radiances 1 m above plant canopies with a 22deg field of view and a 0deg nadir view zenith angle. Canopy and plant measurements were made at the R3 grain fill reproductive stage on 3-4 replicate N application plots provided seasonal inputs of 280, 140, 70, and 28 kg N/ha. Leaf level measurements were also made which included ChlF, photosynthesis, and leaf constituents (photosynthetic pigment, carbon (C), and N contents). Crop yields were determined at harvest. SIF intensities for ChlF were derived directly from canopy reflectance spectra in specific narrowband regions associated with atmospheric oxygen absorption features centered at 688 and 760 nm. The red/far-red S F ratio derived from these field reflectance spectra successfully discriminated foliar pigment levels (e.g., total chlorophyll, Chl) associated with N application rates in both corn crops. This canopy-level spectral ratio was also

  10. High-resolution spectra of the 3.29 micron interstellar emission feature - A summary

    NASA Technical Reports Server (NTRS)

    Tokunaga, A. T.; Sellgren, K.; Smith, R. G.; Nagata, T.; Sakata, A.; Nakada, Y.

    1991-01-01

    High spectral resolution observations of the 3.29-micron interstellar emission feature show two types of profiles. Type 1 has a central wavelength of 3.289-micron and is observed in extended objects such as planetary nebulae and H II regions. Type 2 has a central wavelength of 3.296 microns and is observed around a small number of stellar sources. Type 2 has a full width at half-maximum of 0.020 micron; Type 1 has a broader FWHM, perhaps as much as 0.042 micron, but this is uncertain because of contamination by Pf(delta) emission. These profiles are tabulated for comparison to laboratory data. It is found that no proposed identification for the 3.29-micron emission feature definitely matches the observational spectra, although amorphous aromatic materials and heated polycyclic aromatic hydrocarbons tend to fit the best.

  11. High-Resolution Infrared Imaging and Spectroscopy of the Pistol Nebula: Evidence for Ejection

    NASA Astrophysics Data System (ADS)

    Figer, Donald F.; Morris, Mark; Geballe, T. R.; Rich, R. Michael; Serabyn, Eugene; McLean, Ian S.; Puetter, R. C.; Yahil, Amos

    1999-11-01

    We present new infrared images, obtained with the Hubble Space Telescope (HST) Near-Infrared Camera and Multiobject Spectrometer (NICMOS), and Brα (4.05 μm) spectroscopy, obtained using CGS4 on UKIRT, of the Pistol Star and its associated nebula. We find strong evidence to support the hypothesis that the Pistol Nebula was ejected from the Pistol Star. The Paα (1.87 μm) NICMOS image shows that the nebula completely surrounds the Pistol Star, although the line intensity is much stronger on its northern and western edges. The Brα CGS4 spectra show the classical ringlike signature of quasi-spherical expansion. The blueshifted emission (Vmax~-60 km s-1) is much weaker than the redshifted emission (Vmax~+10 km s-1), where the velocities are with respect to the velocity of the Pistol Star; further, the redshifted emission spans a very narrow range of velocities, i.e., it appears ``flattened'' in the position-velocity diagram. These data suggest that the nebula was ejected from the star several thousand years ago, with a velocity between the current terminal velocity of the stellar wind (95 km s-1) and the present expansion velocity of gas in the outer shell of the nebula (60 km s-1). The Paα image reveals several emission-line stars in the region, including two newly identified emission-line stars north of the Pistol Star, both of which are likely to be the hottest known stars in the Galactic center with spectral types earlier than WC8 and Teff>50,000 K). The presence of these stars, the morphology of the Paα emission, and the velocity field in the gas suggest that the side of the nebula farthest from us is approaching, and being ionized by, the hot stars of the Quintuplet and that the highest velocity redshifted gas has been decelerated by winds from the Quintuplet stars. We also discuss the possibility that the nebular gas might be magnetically confined by the ambient magnetic field delineated by the nearby nonthermal filaments. Based on observations with the

  12. Voigt profile introduces optical depth dependent systematic errors - Detected in high resolution laboratory spectra of water

    NASA Astrophysics Data System (ADS)

    Birk, Manfred; Wagner, Georg

    2016-02-01

    The Voigt profile commonly used in radiative transfer modeling of Earth's and planets' atmospheres for remote sensing/climate modeling produces systematic errors so far not accounted for. Saturated lines are systematically too narrow when calculated from pressure broadening parameters based on the analysis of laboratory data with the Voigt profile. This is caused by line narrowing effects leading to systematically too small fitted broadening parameters when applying the Voigt profile. These effective values are still valid to model non-saturated lines with sufficient accuracy. Saturated lines dominated by the wings of the line profile are sufficiently accurately modeled with a Voigt profile with the correct broadening parameters and are thus systematically too narrow when calculated with the effective values. The systematic error was quantified by mid infrared laboratory spectroscopy of the water ν2 fundamental. Correct Voigt profile based pressure broadening parameters for saturated lines were 3-4% larger than the effective ones in the spectroscopic database. Impacts on remote sensing and climate modeling are expected. Combination of saturated and non-saturated lines in the spectroscopic analysis will quantify line narrowing with unprecedented precision.

  13. Fundamental stellar parameters and metallicities from Bayesian spectroscopy: application to low- and high-resolution spectra

    NASA Astrophysics Data System (ADS)

    Schönrich, Ralph; Bergemann, Maria

    2014-09-01

    We present a unified framework to derive fundamental stellar parameters by combining all available observational and theoretical information for a star. The algorithm relies on the method of Bayesian inference, which for the first time directly integrates the spectroscopic analysis pipeline based on the global spectrum synthesis and allows for comprehensive and objective error calculations given the priors. Arbitrary input data sets can be included into our analysis and other stellar quantities, in addition to stellar age, effective temperature, surface gravity, and metallicity, can be computed on demand. We lay out the mathematical framework of the method and apply it to several observational data sets, including high- and low-resolution spectra (UVES, NARVAL, HARPS, SDSS/SEGUE). We find that simpler approximations for the spectroscopic probability distribution function, which are inherent to past Bayesian approaches, lead to deviations of several standard deviations and unreliable errors on the same data. By its flexibility and the simultaneous analysis of multiple independent measurements for a star, it will be ideal to analyse and cross-calibrate the large ongoing and forthcoming surveys, like Gaia-European Southern Observatory (ESO), SDSS, Gaia and LSST.

  14. Peak fitting and identification software library for high resolution gamma-ray spectra

    NASA Astrophysics Data System (ADS)

    Uher, Josef; Roach, Greg; Tickner, James

    2010-07-01

    A new gamma-ray spectral analysis software package is under development in our laboratory. It can be operated as a stand-alone program or called as a software library from Java, C, C++ and MATLAB TM environments. It provides an advanced graphical user interface for data acquisition, spectral analysis and radioisotope identification. The code uses a peak-fitting function that includes peak asymmetry, Compton continuum and flexible background terms. Peak fitting function parameters can be calibrated as functions of energy. Each parameter can be constrained to improve fitting of overlapping peaks. All of these features can be adjusted by the user. To assist with peak identification, the code can automatically measure half-lives of single or multiple overlapping peaks from a time series of spectra. It implements library-based peak identification, with options for restricting the search based on radioisotope half-lives and reaction types. The software also improves the reliability of isotope identification by utilizing Monte-Carlo simulation results.

  15. New Measurement of Singly Ionized Selenium Spectra by High Resolution Fourier Transform and Grating Spectroscopy

    NASA Astrophysics Data System (ADS)

    Hala, Noman; Nave, G.; Kramida, A.; Ahmad, T.; Nahar, S.; Pradhan, A.

    2015-05-01

    We report new measurements of singly ionised selenium, an element of the iron group detected in nearly twice as many planetary nebulae as any other trans-iron element. We use the NIST 2 m UV/Vis/IR and FT700 UV/Vis Fourier transform spectrometers over the wavelength range of 2000 Å-2.5 μm, supplemented in the lower wavelength region 300-2400 Å with grating spectra taken on a 3-m normal incidence vacuum spectrograph. The analysis of Se II is being extended, covering the wide spectral region from UV to IR. From our investigation, we found serious inconsistency and incompleteness in the previously published results, where several levels were reported without any designation. The analysis is being revised and extended with the help of semiempirical quasi-relativistic Hartree-Fock calculations, starting with the 4s24p3- [4s24p2(4d +5d +5s +6s) +4s4p4] transition array. Out of fifty-two previously reported levels, we rejected thirteen and found several new level values. With the new measurements, we expect to observe transitions between 4s24p2(4d +5s) and 4s24p2(5p +4f), lying in the visible and IR region. A complete interpretation of the level system of both parities will be assisted by least squares fitted parametric calculations. In all, we have already classified about 450 observed lines involving 89 energy levels.

  16. High-resolution spectra of distant compact narrow emission line galaxies: Progrenitors of spheroidal galaxies

    NASA Technical Reports Server (NTRS)

    Koo, David C.; Guzman, Rafael; Faber, S. M.; Illingworth, Garth D.; Bershady, Matthew A.; Kron, Richard G.; Takamiya, Marianne

    1995-01-01

    Emission-line velocity widths have been determined for 17 faint (B approximately 20-23) very blue, compact galaxies whose redshifts range from z = 0.095 to 0.66. The spectra have a resolution of 8 Km/s and were taken with the HIRES echelle spectrograph of the Keck 10 m telescope. The galaxies are luminous with all but two within 1 mag of M(sub B) approximately -21. Yet they exhibit narrow velocity widths between sigma = 28-157 km/s, more consistent with typical values of extreme star-forming galaxies than with those of nearby spiral galaxies of similar luminosity. In particular, objects with sigma is less than or equal to 65 km/s follow the same correlations between sigma and both blue and H beta luminosities as those of nearby H II galaxies. These results strengthen the identification of H II glaxies as thier local counterparts. The blue colors and strong emission lines suggest these compact galaxies are undergoing a recent, strong burst of star formation. Like those which characterize some H II galaxies, this burst could be a nuclear star-forming event within a much larger, older stellar population. If the burst is instead a major episode in the total star-forming history, these distant galaxies could fade enough to match the low luminosities and surface brightnesses typical of nearby spheroidals like NGC 185 or NGC 205. Together with evidence for recent star formation, exponential light profiles, and subsolar metallicities, the postfading correlations between luminosity and velocity width and bewtween luminosity and surface brightness suggest that among the low-sigma galaxies, we may be witnessing, in situ, the progenitors of today's spheroidal galaxies.

  17. Chemical evolution of fluorine in the bulge. High-resolution K-band spectra of giants in three fields

    NASA Astrophysics Data System (ADS)

    Jönsson, H.; Ryde, N.; Harper, G. M.; Cunha, K.; Schultheis, M.; Eriksson, K.; Kobayashi, C.; Smith, V. V.; Zoccali, M.

    2014-04-01

    Context. Possible main formation sites of fluorine in the Universe include asymptotic giant branch (AGB) stars, the ν-process in Type II supernova, and/or Wolf-Rayet stars. The importance of the Wolf-Rayet stars has theoretically been questioned and they are probably not needed in modeling the chemical evolution of fluorine in the solar neighborhood. It has, however, been suggested that Wolf-Rayet stars are indeed needed to explain the chemical evolution of fluorine in the bulge. The molecular spectral data, needed to determine the fluorine abundance, of the often used HF-molecule has not been presented in a complete and consistent way and has recently been debated in the literature. Aims: We intend to determine the trend of the fluorine-oxygen abundance ratio as a function of a metallicity indicator in the bulge to investigate the possible contribution from Wolf-Rayet stars. Additionally, we present here a consistent HF line list for the K- and L-bands including the often used 23 358.33 Å line. Methods: High-resolution near-infrared spectra of eight K giants were recorded using the spectrograph CRIRES mounted at the VLT. A standard setting was used that covered the HF molecular line at 23 358.33 Å. The fluorine abundances were determined using spectral fitting. We also re-analyzed five previously published bulge giants observed with the Phoenix spectrograph on Gemini using our new HF molecular data. Results: We find that the fluorine-oxygen abundance in the bulge probably cannot be explained with chemical evolution models that only include AGB stars and the ν-process in supernovae Type II, that is a significant amount of fluorine production in Wolf-Rayet stars is most likely needed to explain the fluorine abundance in the bulge. For the HF line data, we find that a possible reason for the inconsistencies in the literature, where two different excitation energies were used, is two different definitions of the zero-point energy for the HF molecule and therefore

  18. A High Resolution Hydrometer Phase Classifier Based on Analysis of Cloud Radar Doppler Spectra.

    SciTech Connect

    Luke,E.; Kollias, P.

    2007-08-06

    The lifecycle and radiative properties of clouds are highly sensitive to the phase of their hydrometeors (i.e., liquid or ice). Knowledge of cloud phase is essential for specifying the optical properties of clouds, or else, large errors can be introduced in the calculation of the cloud radiative fluxes. Current parameterizations of cloud water partition in liquid and ice based on temperature are characterized by large uncertainty (Curry et al., 1996; Hobbs and Rangno, 1998; Intriery et al., 2002). This is particularly important in high geographical latitudes and temperature ranges where both liquid droplets and ice crystal phases can exist (mixed-phase cloud). The mixture of phases has a large effect on cloud radiative properties, and the parameterization of mixed-phase clouds has a large impact on climate simulations (e.g., Gregory and Morris, 1996). Furthermore, the presence of both ice and liquid affects the macroscopic properties of clouds, including their propensity to precipitate. Despite their importance, mixed-phase clouds are severely understudied compared to the arguably simpler single-phase clouds. In-situ measurements in mixed-phase clouds are hindered due to aircraft icing, difficulties distinguishing hydrometeor phase, and discrepancies in methods for deriving physical quantities (Wendisch et al. 1996, Lawson et al. 2001). Satellite-based retrievals of cloud phase in high latitudes are often hindered by the highly reflecting ice-covered ground and persistent temperature inversions. From the ground, the retrieval of mixed-phase cloud properties has been the subject of extensive research over the past 20 years using polarization lidars (e.g., Sassen et al. 1990), dual radar wavelengths (e.g., Gosset and Sauvageot 1992; Sekelsky and McIntosh, 1996), and recently radar Doppler spectra (Shupe et al. 2004). Millimeter-wavelength radars have substantially improved our ability to observe non-precipitating clouds (Kollias et al., 2007) due to their excellent

  19. The 4 micron spectra of compact infrared sources

    NASA Technical Reports Server (NTRS)

    Hofmann, R.; Larson, H. P.; Fink, U.

    1986-01-01

    High resolution 5 arcsec spectra in the 4 micron region are presented of the central 5 arcsec of the compact near infrared sources K3-50, W51-IRS2 East, and G333.6-0.2. From measured Br-alpha/Pf-beta line ratios and previously published infrared and radio maps, it is concluded that standard recombination theory fails to explain our observations in at least two cases. It is demonstrated that the data are consistent with thermal excitation of the hydrogen lines in strong stellar winds. The Pf-beta Hu-epsilon line ratio, which is completely insensitive to differential extinction, confirms the need for the stellar wind model for the core of G333.6-0.2. From the (K III) line it is estimated that the potassium abundance in G333.6-0.2 is at least equal to the solar value, and possibly enhanced by a factor up to 10.

  20. Vibronic fine structure in high-resolution x-ray absorption spectra from ion-bombarded boron nitride nanotubes

    SciTech Connect

    Petravic, Mladen; Peter, Robert; Varasanec, Marijana; Li Luhua; Chen Ying; Cowie, Bruce C. C.

    2013-05-15

    The authors have applied high-resolution near-edge x-ray absorption fine structure measurements around the nitrogen K-edge to study the effects of ion-bombardment on near-surface properties of boron nitride nanotubes. A notable difference has been observed between surface sensitive partial electron yield (PEY) and bulk sensitive total electron yield (TEY) fine-structure measurements. The authors assign the PEY fine structure to the coupling of excited molecular vibrational modes to electronic transitions in NO molecules trapped just below the surface. Oxidation resistance of the boron nitride nanotubes is significantly reduced by low energy ion bombardment, as broken B-N bonds are replaced by N-O bonds involving oxygen present in the surface region. In contrast to the PEY spectra, the bulk sensitive TEY measurements on as-grown samples do not exhibit any fine structure while the ion-bombarded samples show a clear vibronic signature of molecular nitrogen.

  1. High-resolution soft X-ray spectra of Scorpius X-1 - The structure of circumsource accreting material

    NASA Technical Reports Server (NTRS)

    Kahn, S. M.; Seward, F. D.; Chlebowski, T.

    1984-01-01

    Four observations of Scorpius X-1 with the Objective Grating Spectrometer of the Einstein Observatory have provided high-resolution spectra (lambda/Delta lambda = approximately 20-50) in the wavelength range 7-46 A. The spectra reveal the presence of absorption structure due to oxygen, nitrogen, and iron, and variable emission structure associated with ionized iron and nitrogen. The strengths of these features suggest that the N/O abundance ratio in the absorbing and line emitting gas is anomalously high, which might indicate that these spectral components are associated with processed material, probably accreting matter transferred from the surface of an evolved companion. Constraints on the inclination of the system, however, imply that this cool, dense, accreting material must be well out of the plane of the binary system. Possible models for the origin and nature of this circumsource medium are discussed. An extensive discussion of the calibration of the Objective Grating Spectrometer and of the analysis of spectra acquired by that instrument is also provided.

  2. Infrared spectra of thyroid tumor tissues

    NASA Astrophysics Data System (ADS)

    Tolstorozhev, G. B.; Skornyakov, I. V.; Butra, V. A.

    2010-07-01

    We used infrared spectroscopy methods to study thyroid tumor tissues removed during surgery. The IR spectra of the surgical material are compared with data from histological examination. We show that in malignant neoplasms, the spectra of proteins in the region of C=O vibrations are different from the spectra of these substances in benign tumors and in tissues outside the pathological focus at a distance >1 cm from the margin of the tumor. The differences in the spectra are due to changes in the supermolecular structure of the proteins, resulting from rearrangement of the system of hydrogen bonds. We identify the spectral signs of malignant pathologies.

  3. Improved Experimental and Theoretical Energy Levels of Carbon I from Solar Infrared Spectra

    NASA Technical Reports Server (NTRS)

    Chang, Edward S.; Geller, Murray

    1997-01-01

    We have improved the energy levels in neutral carbon using high resolution infrared solar spectra. The main source is the ATMOS spectrum measured by the Fourier transaform spectroscopy technique from 600 to 4800 cm-1, supplemented by the MARK IV balloon data, covering from 4700 to 5700 cm-1.

  4. A high-resolution atlas of the infrared spectrum of the Sun and the Earth atmosphere from space. Volume 3: Key to identification of solar features

    NASA Technical Reports Server (NTRS)

    Geller, Murray

    1992-01-01

    During the period April 29 through May 2, 1985, the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment was operated as part of the Spacelab-3 (SL-3) payload on the shuttle Challenger. The instrument, a Fourier transform spectrometer, recorded over 2000 infrared solar spectra from an altitude of 360 km. Although the majority of the spectra were taken through the limb of the Earth's atmosphere in order to better understand its composition, several hundred of the 'high-sun' spectra were completely free from telluric absorption. These high-sun spectra recorded from space are, at the present time, the only high-resolution infrared spectra ever taken of the Sun free from absorptions due to constituents in the Earth's atmosphere. Volumes 1 and 2 of this series provide a compilation of these spectra arranged in a format suitable for quick-look reference purposes and are the first record of the continuous high-resolution infrared spectrum of the Sun and the Earth's atmosphere from space. In the Table of Identifications, which constitutes the main body of this volume, each block of eight wavenumbers is given a separate heading and corresponds to a page of two panels in Volume 1 of this series. In addition, three separate blocks of data available from ATMOS from 622-630 cm(exp -1), 630-638 cm(exp -1) and 638-646 cm(exp -1), excluded from Volume 1 because of the low signal-to-noise ratio, have been included due to the certain identification of several OH and NH transitions. In the first column of the table, the corrected frequency is given. The second column identifies the molecular species. The third and fourth columns represent the assigned transition. The fifth column gives the depth of the molecular line in millimeters. Also included in this column is a notation to indicate whether the line is a blend or lies on the shoulder(s) of another line(s). The final column repeats a question mark if the line is unidentified.

  5. A high-resolution far-infrared survey of the W31 region

    NASA Technical Reports Server (NTRS)

    Wright, E. L.; Fazio, G. G.; Low, F. J.

    1977-01-01

    A 1-m balloon-borne telescope was used to conduct a far-infrared survey of the W31 region at an effective wavelength of 69 microns with a resolution of 1 arcmin. Within this region seven far-infrared sources were observed. Five of these sources were associated with thermal radio emission. For each of these sources the infrared luminosity is much greater than the Ly-alpha luminosity, a situation requiring either dust absorption of Lyman-continuum photons or a large nonionizing stellar luminosity. Two faint infrared sources had no radio counterparts. Far-infrared radiation was not detected from two known radio sources and from one midinfrared source in this region.

  6. High-resolution SO2 isotopologue spectra as evidence for sulfur MIF due to SO2 self-shielding

    NASA Astrophysics Data System (ADS)

    Lyons, J. R.; Stark, G.; Blackie, D.; Pickering, J. C.

    2009-12-01

    It is well known that photolysis of some gas-phase molecules can lead to isotopic mass-independent fractionation (MIF). Several mechanisms for photolytic MIF have been proposed including 1) self-shielding during photon absorption, 2) variations in band oscillator strengths, 3) hyperfine effects, and 4) resonant curve crossing. Self-shielding, a result of line saturation in molecules with line-type absorption spectra, is observed (and predicted) in CO and N2, both of which undergo predissociation. Here, we focus on the role of self-shielding in SO2, also a predissociating molecule. Photolysis of atmospheric SO2 is believed to be the source of sulfur isotope MIF measured in early Earth sedimentary rocks (Farquhar et al. 2000). Quantitative evaluation of this hypothesis requires accurate and high-resolution absorption cross section data. We have completed 1 cm-1 resolution measurements of 32SO2, 33SO2 and 34SO2 isotopologues using a Fourier transform spectrometer (FTS) at Imperial College (IC). A detailed description of the FTS measurements will be presented by D. Blackie et al. (this meeting). Here, we present a brief overview of the data, comparison with recently published lower resolution cross section data of Danielachet et al. (2008), and interpretation via atmospheric modeling. FTS measurements were obtained at 3 pressures (0.1, 0.2 and 0.4 torr) on pure xSO2 gas (x = 32, 33 or 34) from 222 to 188 nm. Spectra were coadded to improve S/N. Visual comparison of our spectra with the lower resolution (~ 20 cm-1) spectra of Danielache et al. (2008) reveals good overall agreement for all 3 isotopologues, although the lower resolution data is unable to resolve the dense rotational structure. However, radiative transfer calculations utilizing the two sets of cross section data in a 1-D atmospheric chemistry code (assuming 10 ppb SO2) yield very different photolytic isotope fractionations. The IC cross sections yield increasing δ34S, δ33S and Δ33S values for

  7. Systematic trend of water vapour absorption in red giant atmospheres revealed by high resolution TEXES 12 μm spectra

    NASA Astrophysics Data System (ADS)

    Ryde, N.; Lambert, J.; Farzone, M.; Richter, M. J.; Josselin, E.; Harper, G. M.; Eriksson, K.; Greathouse, T. K.

    2015-01-01

    Context. The structures of the outer atmospheres of red giants are very complex. Recent interpretations of a range of different observations have led to contradictory views of these regions. It is clear, however, that classical model photospheres are inadequate to describe the nature of the outer atmospheres. The notion of large optically thick molecular spheres around the stars (MOLspheres) has been invoked in order to explain spectro-interferometric observations and low- and high-resolution spectra. On the other hand high-resolution spectra in the mid-IR do not easily fit into this picture because they rule out any large sphere of water vapour in LTE surrounding red giants. Aims: In order to approach a unified scenario for these outer regions of red giants, more empirical evidence from different diagnostics are needed. Our aim here is to investigate high-resolution, mid-IR spectra for a range of red giants, spanning spectral types from early K to mid M. We want to study how the pure rotational lines of water vapour change with effective temperature, and whether we can find common properties that can put new constraints on the modelling of these regions, so that we can gain new insights. Methods: We have recorded mid-IR spectra at 12.2 - 12.4 μm at high spectral resolution of ten well-studied bright red giants, with TEXES mounted on the IRTF on Mauna Kea. These stars span effective temperatures from 3450 K to 4850 K. Results: We find that all red giants in our study cooler than 4300 K, spanning a wide range of effective temperatures (down to 3450 K), show water absorption lines stronger than expected and none are detected in emission, in line with what has been previously observed for a few stars. The strengths of the lines vary smoothly with spectral type. We identify several spectral features in the wavelength region that are undoubtedly formed in the photosphere. From a study of water-line ratios of the stars, we find that the excitation temperatures, in the

  8. An Infrared High Resolution Spectroscopic Abundance Study of the Metal-Poor Giant HD 122563

    NASA Astrophysics Data System (ADS)

    Sneden, Christopher; Afsar, Melike; Jaffe, Daniel Thomas; Kim, Hwiyun; Mace, Gregory

    2015-01-01

    A high resolution, high signal-to-noise spectrum of the very metal-poor giant star HD 122563 has been obtained with the newly commissioned IGRINS H- and K-band high resolution (R = 40,000) spectrograph on the McDonald Observatory 2.7m Smith telescope. With complete spectral coverage in the range 1.5-1.8 and 1.9-2.4 microns and high signal-to-noise (S/N > 200) in the reduced spectrum, we have so far detected about 50neutral-species transitions of elements Na, Mg, Al, Si, Ca, and Fe, as well as many transitions of OH and CO.Assuming atmosphere parameters from the literature of this well-studied bright giant (Teff~4600K, log(g)~1.3) we have derived a metallicity of [Fe/H] = -2.8, in agreement with past results. The alpha-elements are enhanced: [(Mg,Si,Ca)/Fe] = +0.3 to +0.4. The OH lines yield an O abundance in good accord with past claims from analyses of the [O I] lines in the visible part of the spectrum. Study of other features in the IGRINSspectrum is ongoing.Support for this research from the US National Science Foundation (AST-1211585) and the The Scientific and Technological Research Council of Turkey (TÜBITAK, project No. 112T929) are acknowledged with thanks.

  9. Fast acquisition of high-resolution NMR spectra in inhomogeneous fields via intermolecular double-quantum coherences

    PubMed Central

    Chen, Zhong; Cai, Shuhui; Chen, Zhiwei; Zhong, Jianhui

    2009-01-01

    A pulse sequence, IDEAL-II, is proposed based on the concept of intermolecular dipolar-interaction enhanced all lines [Z. Chen et al., J. Am. Chem. Soc. 126, 446 (2004)] for obtaining one-dimensional (1D) high-resolution liquid NMR spectra in inhomogeneous fields via two-dimensional acquisitions. With the new acquisition scheme, the range of magnetic field inhomogeneity rather than chemical shift is sampled in the indirect dimension. This enables a great reduction in acquisition time and amount of data, much improved over the original IDEAL implementation. It is applicable to both isolated and J-coupled spin systems in liquid. For the latter, apparent J coupling constants are magnified threefold in spectra obtained with this sequence. This allows a more accurate measurement of J coupling constants in the cases of small J coupling constants or large inhomogeneous fields. Analytical expression was derived based on intermolecular multiple-quantum coherence treatments. Solution samples that were purposely deshimmed and biological samples with intrinsic field inhomogeneities were tested. Experimental results demonstrate that this sequence retains useful structural information including chemical shifts, relative peak areas, and multiplet patterns of J coupling even when the field inhomogeneity is severe enough to almost erase all spectroscopic information with conventional 1D single-quantum coherence techniques. This sequence is more applicable to weakly coupled and uncoupled spin systems, potentially useful for studying metabolites in in vivo NMR spectroscopy and for characterizing technologically important new materials in combinatorial chemistry. PMID:19256612

  10. Modelling the Emission And/or Absorption Features in the High Resolution Spectra of the Southern Binary System: HH Car

    NASA Astrophysics Data System (ADS)

    Koseoglu, Dogan; Bakış, Hicran

    2016-07-01

    High-resolution spectra (R=48000) of the southern close binary system, HH Car, has been analyzed with modern analysis techniques. Precise absolute parameters were derived from the simultaneous solution of the radial velocity, produced in this study and the light curves, published. According to the results of these analyses, the primary component is an O9 type main sequence star while the secondary component is a giant/subgiant star with a spectral type of B0. Hα emissions can be seen explicitly in the spectra of HH Car. These features were modelled using the absolute parameters of the components. Since components of HH Car are massive early-type stars, mass loss through stellar winds can be expected. This study revealed that the components of HH Car have stellar winds and the secondary component loses mass to the primary. Stellar winds and the gas stream between the components were modelled as a hot shell around the system. It is determined that the interaction between the winds and the gas stream leads to formation of a high temperature impact region.

  11. Measurement of Short-Lived Fission-Product Yields of URANIUM-235 Using High-Resolution Gamma Spectra.

    NASA Astrophysics Data System (ADS)

    Tipnis, Sameer Vijay

    Independent yields of short-lived fission products produced by the thermal neutron induced fission of ^{235}U were determined from the measurements of high resolution gamma spectra. Comparisons were made to the recommended yield values tabulated in the ENDF/B-VI evaluated fission-product data base. Measurements of the gamma spectra were made with a high purity germanium detector (HPGe) using a NaI(Tl) annulus for Compton suppression. Use of beta-gamma coincidence reduced the random background and also allowed a precise definition of the delay time. The experiment was carried out at the 5.5 MV Van de Graaff facility at the University of Massachusetts Lowell. Rapid transfer of the fission fragments to a low background counting environment, a crucial factor in determining the yields of short-lived fission products, was enabled by a helium -jet tape transport system. The recommended yields in the evaluated data file are a combination of experimental and model-predicted values. The latter source is used since data from many short-lived fission products is still missing or poorly known. The results presented here, especially the ones for the very short-lived isotopes may be used to reduce the uncertainties associated with some of the existing values or to replace model-predicted yields. Gaussian distributions of elemental yields, based on the set of experimentally determined independent yields were examined. The feasibility of predicting unmeasured yields on the basis of charge and mass complementarity was also addressed.

  12. Line shapes and satellites in high-resolution x-ray photoelectron spectra of large pi-conjugated organic molecules.

    PubMed

    Schöll, A; Zou, Y; Jung, M; Schmidt, Th; Fink, R; Umbach, E

    2004-11-22

    We present a high-resolution C1s and O1 s x-ray photoemission (XPS) study for condensed films of pi-conjugated organic molecules, namely, of the anhydrides 3,4,9,10-perylene-tetracarboxylic acid dianhydride, 1,4,5,8-naphthalene-tetracarboxylic acid dianhydride, 1,8-naphthalene dicarboxylic acid anhydride, and benzoperylene-(1,8)-dicarboxylic acid anhydride as well as the quinoic acenaphthenequinone. Although the functional groups are identical for the anhydrides, the molecules show very different photoemission fine structure thus providing a detailed fingerprint. A simultaneous peak fit analysis of the XPS spectra of all molecules allows to consistently determine the ionization potentials of all chemically different carbon and oxygen atoms. Additional structures in the C1s and O1s spectra are interpreted as shakeup satellites and assigned with the help of singles and doubles configuration interaction calculations. These satellites provide further information on multielectron excitations and must be taken into account for quantitative investigations. PMID:15549902

  13. HIGH-RESOLUTION INFRARED IMAGING AND SPECTROSCOPY OF THE Z CANIS MAJORIS SYSTEM DURING QUIESCENCE AND OUTBURST

    SciTech Connect

    Hinkley, Sasha; Hillenbrand, Lynne; Crepp, Justin R.; Oppenheimer, Ben R.; Zimmerman, Neil; Brenner, Douglas; Rice, Emily L.; Pueyo, Laurent; Vasisht, Gautam; Roberts, Jennifer E.; Roberts, Lewis C. Jr.; Burruss, Rick; Wallace, J. Kent; Cady, Eric; Zhai, Chengxing; Kraus, Adam L.; Ireland, Michael J.; Beichman, Charles; Dekany, Richard; Parry, Ian R.; and others

    2013-01-20

    We present adaptive optics photometry and spectra in the JHKL bands along with high spectral resolution K-band spectroscopy for each component of the Z Canis Majoris system. Our high angular resolution photometry of this very young ({approx}<1 Myr) binary, comprised of an FU Ori object and a Herbig Ae/Be star, was gathered shortly after the 2008 outburst while our high-resolution spectroscopy was gathered during a quiescent phase. Our photometry conclusively determines that the outburst was due solely to the embedded Herbig Ae/Be member, supporting results from earlier works, and that the optically visible FU Ori component decreased slightly ({approx}30%) in luminosity during the same period, consistent with previous works on the variability of FU Ori type systems. Further, our high-resolution K-band spectra definitively demonstrate that the 2.294 {mu}m CO absorption feature seen in composite spectra of the system is due solely to the FU Ori component, while a prominent CO emission feature at the same wavelength, long suspected to be associated with the innermost regions of a circumstellar accretion disk, can be assigned to the Herbig Ae/Be member. These findings clarify previous analyses of the origin of the CO emission in this complex system.

  14. Infrared spectra of protostellar collapse

    NASA Technical Reports Server (NTRS)

    Hollenbach, David J.; Ceccarelli, Cecilia; Neufeld, David A.; Tielens, Alexander G. G. M.

    1995-01-01

    Theoretical models of the formation of low mass stars by cloud collapse predict that OI(63 micrometers) and IR rotational lines of CO and H2O dominate the cooling in the freefalling region 10-1000 AU from the protostar. The freefalling gas supersonically hits the protoplanetary disk orbiting the protostar, forming an accretion shock with strong IR emission in rotational lines of H2O and OH, and OI(63 microns). The accretion shock spectra and line profiles depend on the mass flux through the shock and the typical distance r-bar at which the freefalling gas strikes the disk. The line widths are of order the Keplerian speed, or approx. 10(r-bar/10AU)(exp -0.5) km/s, for the accretion shock lines, and less for the lines from the infalling gas. Measurements of the IR line fluxes and profiles from the freefalling gas and the accretion shock diagnoses how a protostar and disk are formed and requires high sensitivity and high spectral and spatial resolving power. SOFIA will be the optimum observatory for many of these lines, although ISO will contribute and the KAO may make a few pioneering detections.

  15. IN-SYNC I: Homogeneous stellar parameters from high-resolution apogee spectra for thousands of pre-main sequence stars

    SciTech Connect

    Cottaar, Michiel; Meyer, Michael R.; Covey, Kevin R.; Nidever, David L.; Stassun, Keivan G.; Foster, Jonathan B.; Tan, Jonathan C.; Da Rio, Nicola; Chojnowski, S. Drew; Skrutskie, Michael; Majewski, Steven R.; Wilson, John C.; Zasowski, Gail; Flaherty, Kevin M.; Frinchaboy, Peter M.

    2014-10-20

    Over two years, 8859 high-resolution H-band spectra of 3493 young (1-10 Myr) stars were gathered by the multi-object spectrograph of the APOGEE project as part of the IN-SYNC ancillary program of the SDSS-III survey. Here we present the forward modeling approach used to derive effective temperatures, surface gravities, radial velocities, rotational velocities, and H-band veiling from these near-infrared spectra. We discuss in detail the statistical and systematic uncertainties in these stellar parameters. In addition, we present accurate extinctions by measuring the E(J – H) of these young stars with respect to the single-star photometric locus in the Pleiades. Finally, we identify an intrinsic stellar radius spread of about 25% for late-type stars in IC 348 using three (nearly) independent measures of stellar radius, namely, the extinction-corrected J-band magnitude, the surface gravity, and the Rsin i from the rotational velocities and literature rotation periods. We exclude that this spread is caused by uncertainties in the stellar parameters by showing that the three estimators of stellar radius are correlated, so that brighter stars tend to have lower surface gravities and larger Rsin i than fainter stars at the same effective temperature. Tables providing the spectral and photometric parameters for the Pleiades and IC 348 have been provided online.

  16. EpiProfile Quantifies Histone Peptides With Modifications by Extracting Retention Time and Intensity in High-resolution Mass Spectra*

    PubMed Central

    Yuan, Zuo-Fei; Lin, Shu; Molden, Rosalynn C.; Cao, Xing-Jun; Bhanu, Natarajan V.; Wang, Xiaoshi; Sidoli, Simone; Liu, Shichong; Garcia, Benjamin A.

    2015-01-01

    Histone post-translational modifications contribute to chromatin function through their chemical properties which influence chromatin structure and their ability to recruit chromatin interacting proteins. Nanoflow liquid chromatography coupled with high resolution tandem mass spectrometry (nanoLC-MS/MS) has emerged as the most suitable technology for global histone modification analysis because of the high sensitivity and the high mass accuracy of this approach that provides confident identification. However, analysis of histones with this method is even more challenging because of the large number and variety of isobaric histone peptides and the high dynamic range of histone peptide abundances. Here, we introduce EpiProfile, a software tool that discriminates isobaric histone peptides using the distinguishing fragment ions in their tandem mass spectra and extracts the chromatographic area under the curve using previous knowledge about peptide retention time. The accuracy of EpiProfile was evaluated by analysis of mixtures containing different ratios of synthetic histone peptides. In addition to label-free quantification of histone peptides, EpiProfile is flexible and can quantify different types of isotopically labeled histone peptides. EpiProfile is unique in generating layouts (i.e. relative retention time) of histone peptides when compared with manual quantification of the data and other programs (such as Skyline), filling the need of an automatic and freely available tool to quantify labeled and non-labeled modified histone peptides. In summary, EpiProfile is a valuable nanoflow liquid chromatography coupled with high resolution tandem mass spectrometry-based quantification tool for histone peptides, which can also be adapted to analyze nonhistone protein samples. PMID:25805797

  17. Collecting, analyzing and archiving of ground based infrared solar spectra obtained from several locations

    NASA Technical Reports Server (NTRS)

    Murcray, David G.; Murcray, Frank J.; Goldman, Aaron; Mcelroy, Charles T.; Chu, William P.; Rinsland, Curtis P.; Woods, Peter; Matthews, W. A.; Johnston, P. V.

    1990-01-01

    The infrared solar spectrum as observed from the ground under high resolution contains thousands of absorption lines. The majority of these lines are due to compounds that are present in the Earth's atmosphere. Ground based infrared solar spectra contain information concerning the composition of the atmosphere at the time the spectra were obtained. The objective of this program is to record solar spectra from various ground locations, and to analyze and archive these spectra. The analysis consists of determining, for as many of the absorption lines as possible, the molecular species responsible for the absorption, and to verify that current models of infrared transmission match the observed spectra. Archiving is an important part of the program, since a number of the features in the spectra have not been identified. At some later time, when the features are identified, it will be possible to determine the amount of that compound that was present in the atmosphere at the time the spectrum was taken.

  18. Far Infrared High Resolution Synchrotron FTIR Spectroscopy of the Low Frequency Bending Modes of Dmso

    NASA Astrophysics Data System (ADS)

    Cuisset, Arnaud; Smirnova, Irina; Bocquet, Robin; Hindle, Francis; Mouret, Gael; Sadovskii, Dmitrii A.; Pirali, Olivier; Roy, Pascale

    2010-06-01

    In addition to its importance for industrial and environmental studies, the monitoring of DiMethylSulfOxyde (DMSO, (CH_3)_2SO) concentrations is of considerable interest for civil protection. The existing high resolution gas phase spectroscopic data of DMSO only concerned the pure rotational transitions in the ground state. In the Far-IR domain, the low-frequency rovibrational transitions have never previously resolved. The high brightness of the AILES beamline of the synchrotron SOLEIL and the instrumental sensitivity provided by the multipass cell allowed to measure for the first time these transitions. 1581 A-type and C-type transitions in the ν11 band have been assigned and 25 molecular constants of Watson's s-form hamiltonian developed to degree 8 have been fitted within the experimental accuracy. The use of then synchrotron radiation has opened many possibilities for new spectroscopic studies. Together with several other recent studies, our successful measurement and analysis of DMSO convincingly demonstrates the potential of the AILES beamline for high resolution FIR spectroscopy. Thus our present work is just at the beginning of unraveling the rovibrational structure of low frequency bending and torsional vibrational states of DMSO and yielding important comprehensive structural and spectroscopic information on this molecule. L. Margules, R. A. Motienko, E. A. Alekseev, J. Demaison, J. Molec. Spectrosc., 260(23),2009 V. Typke, M. Dakkouri, J. Molec. Struct., 599(177),2001 A. Cuisset, L. Nanobashvili, I. Smirnova, R. Bocquet, F. Hindle, G. Mouret, O. Pirali, P. Roy, D. Sadovskii, Chem. Phys. Lett., accepted for publication

  19. Spectral Assignments and Analysis of the Ground State of Nitromethane in High-Resolution FTIR Synchrotron Spectra

    NASA Astrophysics Data System (ADS)

    Twagirayezu, Sylvestre; Billinghurst, Brant E.; May, Tim E.; Dawadi, Mahesh B.; Perry, David S.

    2014-06-01

    The Fourier Transform infrared spectra of CH3NO2, have been recorded, in the 400-950 wn spectral region, at a resolution of 0.00096 wn, using the Far-Infrared Beamline at Canadian Light Source. The observed spectra contain four fundamental vibrations: the NO2 in-plane rock (475.2 wn), the NO2 out-of-plane rock (604.9 wn), the NO2 symmetric bend (657.1 wn), and the CN-stretch (917.2 wn). For the lowest torsional state of CN-stretch and NO2 in-plane rock, transitions involving quantum numbers, " = 0; " {≤ 50} and {_a}" {≤ 10}, have been assigned with the aid of an automated ground state combination difference program together with a traditional Loomis Wood approach Ground state combination differences derived from more than 2100 infrared transitions have been fit with the six-fold torsion-rotation program developed by Ilyushin et al. Additional sextic and octic centrifugal distortion parameters are derived for the ground vibrational state. C. F. Neese., An Interactive Loomis-Wood Package, V2.0, {56th},OSU Interanational Symposium on Molecular Spectroscopy (2001). V. V. Ilyushin, Z. Kisiel, L. Pszczolkowski, H. Mader, and J. T. Hougen, J. Mol. Spectrosc., 259, 26, (2010).

  20. High-resolution infrared study of AsH 2D: The stretching fundamental bands ν1/ ν5 and ν2

    NASA Astrophysics Data System (ADS)

    Ulenikov, O. N.; Bekhtereva, E. S.; Yukhnik, Yu. B.; Vershinina, O. G.; Jerzembeck, W.; Bürger, H.

    2008-11-01

    High-resolution (ca. 0.0025 cm -1) Fourier transform infrared spectra of AsH 2D were recorded in the regions of the As-H and As-D stretching fundamental bands ν1/ ν5 and ν2, respectively, and analyzed. Strong resonance interactions between the bands ν1 and ν5, and also between the band ν2 and the bending overtone band 2 ν4 were established. From transitions observed in the ν1 and ν5 bands ground state rotational energies for larger values of rotational quantum numbers than previously available could be determined. Thereof improved ground state rotational parameters were derived. More than 3200 assigned transitions corresponding to 1059 upper state energy levels which were almost equally distributed over the three stretching states were fitted with an rms-deviation of 0.00031 cm -1, which corresponds to experimental precision.

  1. High-resolution 3-μm spectra of Jupiter: Latitudinal spectral variations influenced by molecules, clouds, and haze

    NASA Astrophysics Data System (ADS)

    Kim, Sang J.; Geballe, T. R.; Kim, J. H.; Jung, A.; Seo, H. J.; Minh, Y. C.

    2010-08-01

    We present latitudinally-resolved high-resolution ( R = 37,000) pole-to-pole spectra of Jupiter in various narrow longitudinal ranges, in spectral intervals covering roughly half of the spectral range 2.86-3.53 μm. We have analyzed the data with the aid of synthetic spectra generated from a model jovian atmosphere that included lines of CH 4, CH 3D, NH 3, C 2H 2, C 2H 6, PH 3, and HCN, as well as clouds and haze. Numerous spectral features of many of these molecular species are present and are individually identified for the first time, as are many lines of H3+ and a few unidentified spectral features. In both polar regions the 2.86-3.10-μm continuum is more than 10 times weaker than in spectra at lower latitudes, implying that in this wavelength range the single-scattering albedos of polar haze particles are very low. In contrast, the 3.24-3.53 μm the weak polar and equatorial continua are of comparable intensity. We derive vertical distributions of NH 3, C 2H 2 and C 2H 6, and find that the mixing ratios of NH 3 and C 2H 6 show little variation between equatorial and polar regions. However, the mixing ratios of C 2H 2 in the northern and southern polar regions are ˜6 and ˜3 times, respectively, less than those in the equatorial regions. The derived mixing ratio curves of C 2H 2 and C 2H 6 extend up to the 10 -6 bar level, a significantly higher altitude than most previous results in the literature. Further ground-based observations covering other longitudes are needed to test if these mixing ratios are representative values for the equatorial and polar regions.

  2. Fundamental M-dwarf parameters from high-resolution spectra using PHOENIX ACES models. I. Parameter accuracy and benchmark stars

    NASA Astrophysics Data System (ADS)

    Passegger, V. M.; Wende-von Berg, S.; Reiners, A.

    2016-03-01

    M-dwarf stars are the most numerous stars in the Universe; they span a wide range in mass and are in the focus of ongoing and planned exoplanet surveys. To investigate and understand their physical nature, detailed spectral information and accurate stellar models are needed. We use a new synthetic atmosphere model generation and compare model spectra to observations. To test the model accuracy, we compared the models to four benchmark stars with atmospheric parameters for which independent information from interferometric radius measurements is available. We used χ2-based methods to determine parameters from high-resolution spectroscopic observations. Our synthetic spectra are based on the new PHOENIX grid that uses the ACES description for the equation of state. This is a model generation expected to be especially suitable for the low-temperature atmospheres. We identified suitable spectral tracers of atmospheric parameters and determined the uncertainties in Teff, log g, and [Fe/H] resulting from degeneracies between parameters and from shortcomings of the model atmospheres. The inherent uncertainties we find are σTeff = 35 K, σlog g = 0.14, and σ[Fe/H] = 0.11. The new model spectra achieve a reliable match to our observed data; our results for Teff and log g are consistent with literature values to within 1σ. However, metallicities reported from earlier photometric and spectroscopic calibrations in some cases disagree with our results by more than 3σ. A possible explanation are systematic errors in earlier metallicity determinations that were based on insufficient descriptions of the cool atmospheres. At this point, however, we cannot definitely identify the reason for this discrepancy, but our analysis indicates that there is a large uncertainty in the accuracy of M-dwarf parameter estimates. Based on observations carried out with UVES at ESO VLT.

  3. High-resolution Fourier transform infrared synchrotron spectroscopy of the NO2 in-plane rock band of nitromethane

    NASA Astrophysics Data System (ADS)

    Dawadi, Mahesh B.; Twagirayezu, Sylvestre; Perry, David S.; Billinghurst, Brant E.

    2015-09-01

    The high-resolution rotationally resolved Fourier-transform infrared spectrum of the NO2 in-plane rock band (440-510 cm-1) of nitromethane (CH3NO2) has been recorded using the Far-Infrared Beamline at the Canadian Light Source, with a resolution of 0.00096 cm-1. About 1773 transitions reaching the upper state levels m‧ = 0; Ka‧ ⩽ 7;J‧ ⩽ 50 have been assigned using an automated ground-state combination difference program together with the traditional Loomis-Wood approach. These data from the lowest torsional state, m‧ = 0, were fit using the six-fold torsion-rotation program developed by Ilyushin et al. (2010). The analysis reveals that the rotational energy level structure in the upper vibrational state is similar to that of the ground vibrational state, but the sign and magnitude of high-order constants are significantly changed suggesting the presence of multiple perturbations.

  4. Design inputs for a high-performance high-resolution near-infrared spectrograph

    NASA Astrophysics Data System (ADS)

    Hinkle, Kenneth H.; Joyce, Richard R.; Najita, Joan R.

    2010-07-01

    The combination of immersion grating and infrared array detector technologies allows the construction of highresolution spectrographs in the near-infrared that have capabilities similar to those of optical spectrographs. It is possible, for instance, to design multi-object spectrographs with very large wavelength coverage and high throughput. We explored the science and functional drivers for these spectrograph designs. Several key inputs into the design are reviewed including risk, mechanical-optical trades, and operations. We discuss a design for a fixed configuration spectrograph with either 1.1 - 2.5 or 3 - 5 μm simultaneous wavelength coverage.

  5. A Combined Synchrotron-Based High Resolution FTIR and Diode Laser Jet Infrared Spectroscopy Study of the Chiral Molecule CDBrClF

    NASA Astrophysics Data System (ADS)

    Albert, S.; Albert, K. Keppler; Quack, M.; Lerch, Ph.; Boudon, V.

    2013-06-01

    The experimental detection of molecular parity violation Δ_{PV}E is of great interest because of its importance in the understanding of fundamental aspects of molecular dynamics and symmetries. One possible method for this is measuring rovibrational or rotational frequency shifts in the infrared or microwave spectra of enantiomers. For that reason we have measured and analysed the rotationally resolved infrared spectrum of CDBrClF as a prototype spectrum for a chiral molecule using three different techniques. The spectrum has been recorded at room temperature with the Zurich Bruker IFS spectrometer ZP 2001 and with the Bruker interferometer 2009 connected to the Swiss synchrotron using a resolution of 0.0007 cm^{-1}. In addition, the IR spectrum of CDBrClF has been measured at low temperature with our diode laser jet setup in the ν_5 region. The spectra of the two major isotopomers CD^{81}Br^{35}ClF and CD^{79}Br^{35}ClF have been analysed within the ν_5 (CCl-stretch), ν_4 (CF-stretch) and ν_3 (CDF-bend) regions. A detailed rovibrational analysis of these bands is presented. The role for possible experiments in the experimental detection of molecular parity violation shall be discussed. M. Quack, Fundamental symmetries and symmetry violations in Handbook of High Resolution Spectroscopy, Vol. 1(Eds. M. Quack and F. Merkt), Wiley, Chichester, New York 2011, 659-722, M. Quack, J. Stohner and M. Willeke, Annu. Rev. Phys. Chem. 2008, 59, 741, A. Bakasov, T.K. Ha, and M. Quack, J. Chem. Phys. 1998, 109, 7263, R. Berger and M. Quack, J. Chem. Phys, 2000, 112, 3148. M. Quack and J. Stohner, Phys. Rev. Lett. 2000, 84, 3807, M. Quack and J. Stohner. J. Chem. Phys., 2003, 119, 11228. S. Albert, K. Keppler Albert and M. Quack, High Resolution Fourier Transform Infrared Spectroscopy in Handbook of High Resolution Spectroscopy, Vol. 2 (Eds. M. Quack and F. Merkt), Wiley, Chichester, New York 2011, 965-1019, S. Albert and M. Quack, ChemPhysChem, 2007, 8, 1271-1281. S. Albert

  6. Surface Temperature Mapping of the University of Northern Iowa Campus Using High Resolution Thermal Infrared Aerial Imageries

    PubMed Central

    Savelyev, Alexander; Sugumaran, Ramanathan

    2008-01-01

    The goal of this project was to map the surface temperature of the University of Northern Iowa campus using high-resolution thermal infrared aerial imageries. A thermal camera with a spectral bandwidth of 3.0-5.0 μm was flown at the average altitude of 600 m, achieving ground resolution of 29 cm. Ground control data was used to construct the pixel- to-temperature conversion model, which was later used to produce temperature maps of the entire campus and also for validation of the model. The temperature map then was used to assess the building rooftop conditions and steam line faults in the study area. Assessment of the temperature map revealed a number of building structures that may be subject to insulation improvement due to their high surface temperatures leaks. Several hot spots were also identified on the campus for steam pipelines faults. High-resolution thermal infrared imagery proved highly effective tool for precise heat anomaly detection on the campus, and it can be used by university facility services for effective future maintenance of buildings and grounds.

  7. High-resolution infrared spectroscopy of Io and possible surface materials

    NASA Technical Reports Server (NTRS)

    Howell, Robert R.; Nash, Douglas B.; Geballe, Thomas R.; Cruikshank, Dale P.

    1989-01-01

    A comparison of new spectra of Io with laboratory-simulated frosts confirms that the dominant materials on Io are SO2 frost in conjunction with a spectrally neutral material presumed to be sulfur. While the 4-micron region spectra are largely explainable in these terms, attention is drawn to a shoulder in the spectrum at 4.04 microns that is suggestive of adsorbed SO2 gas; two shallow, unidentified bands are also noted at 3.85 and 3.91 microns. The isotopic ratios of oxygen and sulfur appear to be normal. The absence of distinct bands in the new spectra in the 5-micron region limits the abundance of sulfate and sulfite compounds.

  8. Phase closure retrieval in an infrared-to-visible upconversion interferometer for high resolution astronomical imaging.

    PubMed

    Ceus, Damien; Tonello, Alessandro; Grossard, Ludovic; Delage, Laurent; Reynaud, François; Herrmann, Harald; Sohler, Wolfgang

    2011-04-25

    This paper demonstrates the use of a nonlinear upconversion process to observe an infrared source through a telescope array detecting the interferometric signal in the visible domain. We experimentally demonstrate the possibility to retrieve information on the phase of the object spectrum of an infrared source by using a three-arm upconversion interferometer. We focus our study on the acquisition of phase information of the complex visibility by means of the phase closure technique. In our experimental demonstration, a laboratory binary star with an adjustable photometric ratio is used as a test source. A real time comparison between a standard three-arm interferometer and our new concept using upconversion by sum-frequency generation demonstrates the preservation of phase information which is essential for image reconstruction. PMID:21643113

  9. High resolution infrared spectroscopy: Some new approaches and applications to planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Mumma, M. J.

    1978-01-01

    The principles of spectral line formation and of techniques for retrieval of atmospheric temperature and constituent profiles are discussed. Applications to the atmospheres of Earth, Mars, Venus, and Jupiter are illustrated by results obtained with Fourier transform and infrared heterodyne spectrometers at resolving powers (lambda/delta hyperon lambda of approximately 10,000 and approximately 10 to the seventh power), respectively, showing the high complementarity of spectroscopy at these two widely different resolving powers. The principles of heterodyne spectroscopy are presented and its applications to atmospheric probing and to laboratory spectroscopy are discussed. Direct absorption spectroscopy with tuneable semiconductor lasers is discussed in terms of precision frequency-and line strength-measurements, showing substantial advances in laboratory infrared spectroscopy.

  10. First far-infrared high resolution analysis of the ν3 band of phosgene 35Cl2CO and 35Cl37ClCO

    NASA Astrophysics Data System (ADS)

    Ndao, M.; Perrin, A.; Kwabia Tchana, F.; Manceron, L.; Flaud, J. M.

    2016-08-01

    The high-resolution absorption spectra of phosgene (Cl2CO) has been recorded at 0.001 cm-1 resolution in the 250-350 cm-1 region by Fourier transform spectroscopy at synchrotron SOLEIL. To reduce the spectral congestion, the spectra have been recorded at low temperature (197 K) using a 93.14 m optical path length cryogenic cell. This enables the first detailed infrared analysis of the ν3 bands of the 35Cl2CO and 35Cl37ClCO isotopologues of phosgene. Using a Watson-type Hamiltonian, it was possible to reproduce the upper state rovibrational infrared energy levels, together with, for 35Cl2CO, the available microwave data in the 31 excited state (Yamamoto et al. 1984) to within their experimental accuracy. In this way, accurate rotational and centrifugal distortion constants together with the following band centers: ν0(ν3, 35Cl2CO) = 301.545622(17) cm-1 and ν0(ν3, 35Cl37ClCO) = 298.199194(81) cm-1, were derived for the ν3 bands of 35Cl2CO and 35Cl37ClCO.

  11. High Resolution Near Infrared Spectrometer to Study the Zodiacal Light Spectrum

    NASA Technical Reports Server (NTRS)

    Kutyrev, Alexander; Arendt, Richard G.; Dwek, Eli; Moseley, Samuel H.; Silverberg, Robert F.; Rapchun, David

    2008-01-01

    We are developing a near infrared spectrometer for measuring solar absorption lines in the zodiacal light in the near infrared region. R. Reynolds at el. (2004, ApJ 612, 1206) demonstrated that observing single Fraunhofer line can be a powerful tool for extracting zodiacal light parameters based on their measurements of the profile of the Mg I line at 5184 A. We are extending this technique to the near infrared with the primary goal of measuring the absolute intensity of the zodiacal light. This measurement will provide the crucial information needed to accurately subtract zodiacal emission from the DIRBE measurements to get a much higher quality measurement of the extragalactic IR background. The instrument design is based on a dual Fabry-Perot interferometer with a narrow band filter. Its double etalon design allows to achieve high spectral contrast to reject the bright out of band telluric OH emission. High spectral contrast is absolutely necessary to achieve detection limits needed to accurately measure the intensity of the absorption line. We present the design, estimated performance of the instrument with the expected results of the observing program.

  12. The Gaia-ESO Survey: The analysis of high-resolution UVES spectra of FGK-type stars

    NASA Astrophysics Data System (ADS)

    Smiljanic, R.; Korn, A. J.; Bergemann, M.; Frasca, A.; Magrini, L.; Masseron, T.; Pancino, E.; Ruchti, G.; San Roman, I.; Sbordone, L.; Sousa, S. G.; Tabernero, H.; Tautvaišienė, G.; Valentini, M.; Weber, M.; Worley, C. C.; Adibekyan, V. Zh.; Allende Prieto, C.; Barisevičius, G.; Biazzo, K.; Blanco-Cuaresma, S.; Bonifacio, P.; Bragaglia, A.; Caffau, E.; Cantat-Gaudin, T.; Chorniy, Y.; de Laverny, P.; Delgado-Mena, E.; Donati, P.; Duffau, S.; Franciosini, E.; Friel, E.; Geisler, D.; González Hernández, J. I.; Gruyters, P.; Guiglion, G.; Hansen, C. J.; Heiter, U.; Hill, V.; Jacobson, H. R.; Jofre, P.; Jönsson, H.; Lanzafame, A. C.; Lardo, C.; Ludwig, H.-G.; Maiorca, E.; Mikolaitis, Š.; Montes, D.; Morel, T.; Mucciarelli, A.; Muñoz, C.; Nordlander, T.; Pasquini, L.; Puzeras, E.; Recio-Blanco, A.; Ryde, N.; Sacco, G.; Santos, N. C.; Serenelli, A. M.; Sordo, R.; Soubiran, C.; Spina, L.; Steffen, M.; Vallenari, A.; Van Eck, S.; Villanova, S.; Gilmore, G.; Randich, S.; Asplund, M.; Binney, J.; Drew, J.; Feltzing, S.; Ferguson, A.; Jeffries, R.; Micela, G.; Negueruela, I.; Prusti, T.; Rix, H.-W.; Alfaro, E.; Babusiaux, C.; Bensby, T.; Blomme, R.; Flaccomio, E.; François, P.; Irwin, M.; Koposov, S.; Walton, N.; Bayo, A.; Carraro, G.; Costado, M. T.; Damiani, F.; Edvardsson, B.; Hourihane, A.; Jackson, R.; Lewis, J.; Lind, K.; Marconi, G.; Martayan, C.; Monaco, L.; Morbidelli, L.; Prisinzano, L.; Zaggia, S.

    2014-10-01

    Context. The ongoing Gaia-ESO Public Spectroscopic Survey is using FLAMES at the VLT to obtain high-quality medium-resolution Giraffe spectra for about 105 stars and high-resolution UVES spectra for about 5000 stars. With UVES, the Survey has already observed 1447 FGK-type stars. Aims: These UVES spectra are analyzed in parallel by several state-of-the-art methodologies. Our aim is to present how these analyses were implemented, to discuss their results, and to describe how a final recommended parameter scale is defined. We also discuss the precision (method-to-method dispersion) and accuracy (biases with respect to the reference values) of the final parameters. These results are part of the Gaia-ESO second internal release and will be part of its first public release of advanced data products. Methods: The final parameter scale is tied to the scale defined by the Gaia benchmark stars, a set of stars with fundamental atmospheric parameters. In addition, a set of open and globular clusters is used to evaluate the physical soundness of the results. Each of the implemented methodologies is judged against the benchmark stars to define weights in three different regions of the parameter space. The final recommended results are the weighted medians of those from the individual methods. Results: The recommended results successfully reproduce the atmospheric parameters of the benchmark stars and the expected Teff-log g relation of the calibrating clusters. Atmospheric parameters and abundances have been determined for 1301 FGK-type stars observed with UVES. The median of the method-to-method dispersion of the atmospheric parameters is 55 K for Teff, 0.13 dex for log g and 0.07 dex for [Fe/H]. Systematic biases are estimated to be between 50-100 K for Teff, 0.10-0.25 dex for log g and 0.05-0.10 dex for [Fe/H]. Abundances for 24 elements were derived: C, N, O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo, Ba, Nd, and Eu. The typical method

  13. High-Resolution Tunable Mid-Infrared Spectrometer Based on Difference-Frequency Generation in AgGaS2

    NASA Astrophysics Data System (ADS)

    Vitcu, Adrian; Ciurylo, Richard; Wehr, Roman; Drummond, James R.; May, A. David

    2004-09-01

    We have built a high-resolution and high-signal-to-noise ratio spectrometer for line shape studies of greenhouse gases in the mid infrared. The infrared radiation is generated in a AgGaS2 nonlinear crystal by the well-known difference-frequency method. The choice of crystal is explained, and a brief literature review is presented. With two tunable dye lasers and a type I, 90° phase-matching geometry, the infrared is continuously tunable from 7 to 9 µm when Rhodamine 6G and Sulforhodamine 640 dyes are used. The total infrared power exceeds 30 nW and is limited by both the damage threshold and thermal loading of the crystal. Phase-sensitive detection allows us to reach signal-to-noise ratios in excess of 3500:1 while maintaining an instrumental linewidth of 1.5 MHz. However, we show that the spectrometer may be used to measure the positions of spectral lines within +/-400 kHz.

  14. Package for Interactive Analysis of Line Emission (Analysis of UV-X-Ray High-Resolution Emission Spectra)

    NASA Technical Reports Server (NTRS)

    Kashyap, Vinay; Hunter, Paul (Technical Monitor)

    2003-01-01

    PINTofALE is an IDL based package to analyze high-resolution grating spectra. The first version was made available to the public on 3 February 2001. Since then we have carried out numerous changes, and the current release is version 1.5, released on 9 October 2002. The changes include upgrades to handle higher versions of IDL, the new version of the CHIANTI database (v4), major enhancements in user-friendliness, improved handling of response matrices, the ability to handle 24-bit color, access to the Atomic Plasma Emission Database (APED), and beta releases of Markov Chain Monte Carlo (MCMC) based DEM fitting routines. Plans for the future include: inclusion of MCMC techniques in the fitting programs, enhanced graphics capabilities, an overhaul of the line and continuum database structure, and bug fixes. In September 2002, we hired a data analyst (LiWei Lin) to work on PINTofALE. Mr.Lin is concentrating on incorporating MCMC as well as simpler Monte-Carlo techniques, fast RMF convolution, etc., into the code base, as well as reviewing the existing documentation and searching for bugs. A detailed description of the package, together with fairly detailed documentation, example walks-throughs, and downloadable tar files, are available on-line from http://hea-www. harvard.edu/PINTofALE/

  15. High-resolution X-ray spectra of solar flares. IV - General spectral properties of M type flares

    NASA Technical Reports Server (NTRS)

    Feldman, U.; Doschek, G. A.; Kreplin, R. W.; Mariska, J. T.

    1980-01-01

    The spectral characteristics in selected narrow regions of the X-ray spectrum of class M solar flares are analyzed. High-resolution spectra in the ranges 1.82-1.97, 2.98-3.07, 3.14-3.24 and 8.26-8.53 A, which contain lines important for the determination of electron temperature and departure from ionization equilibrium, were recorded by spaceborne Bragg crystal spectrometers. Temperatures of up to 20,000,000 K are obtained from line ratios during flare rise phases in M as well as X flares, while in the decay phase the calcium temperature can be as low as 8,000,000 K, which is significantly lower than in X flares. Large nonthermal motions (on the order of 130 km/sec at most) are also observed in M as well as X flares, which are largest during the soft X-ray rise phase. Finally, it is shown that the method proposed by Gabriel and Phillips (1979) for detecting departures of electrons from Maxwellian velocity distributions is not sufficiently sensitive to give reliable results for the present data.

  16. High-resolution KMM radiative Auger x-ray emission spectra of calcium induced by synchrotron radiation

    SciTech Connect

    Cao, W.; Dousse, J.-Cl.; Berset, M.; Fennane, K.; Hoszowska, J.; Maillard, Y.-P.; Szlachetko, M.; Kavcic, M.; Bucar, K.; Budnar, M.; Zitnik, M.; Szlachetko, J.

    2011-04-15

    The KMM radiative Auger (RA) x-ray spectra of solid Ca were induced by monochromatic synchrotron radiation and measured with a high-resolution von Hamos bent crystal spectrometer. Two excitation energies were employed, one in the near K threshold region and the second well above the K absorption edge. The KMM RA spectral structure and relative intensity with respect to the diagram K{beta}{sub 1,3} (K-M{sub 3,2}) line are found to be independent of the excitation energy. The overall RA structure resembles the density of unoccupied s, p, and d states. Due to solid-state effects, however, spectral features resulting from the major discrete shake-up transitions could not be resolved. For the total KMM RA to K{beta}{sub 1,3} yield ratio, a value of 0.053(3) is obtained. The latter is compared to theoretical predictions and available experimental data obtained by various types of target excitation.

  17. Physical properties of the interstellar medium using high-resolution Chandra spectra: O K-edge absorption

    SciTech Connect

    Gatuzz, E.; Mendoza, C.; García, J.; Kallman, T. R.; Bautista, M. A.; Gorczyca, T. W. E-mail: claudio@ivic.gob.ve E-mail: manuel.bautista@wmich.edu E-mail: timothy.r.kallman@nasa.gov

    2014-08-01

    Chandra high-resolution spectra toward eight low-mass Galactic binaries have been analyzed with a photoionization model that is capable of determining the physical state of the interstellar medium. Particular attention is given to the accuracy of the atomic data. Hydrogen column densities are derived with a broadband fit that takes into account pileup effects, and in general are in good agreement with previous results. The dominant features in the oxygen-edge region are O I and O II Kα absorption lines whose simultaneous fits lead to average values of the ionization parameter of log ξ = –2.90 and oxygen abundance of A{sub O} = 0.70. The latter is given relative to the standard by Grevesse and Sauval, but rescaling with the revision by Asplund et al. would lead to an average abundance value fairly close to solar. The low average oxygen column density (N{sub O} = 9.2 × 10{sup 17} cm{sup –2}) suggests a correlation with the low ionization parameters, the latter also being in evidence in the column density ratios N(O II)/N(O I) and N(O III)/N(O I) that are estimated to be less than 0.1. We do not find conclusive evidence for absorption by any other compound but atomic oxygen in our oxygen-edge region analysis.

  18. A comparison of fine structures in high-resolution x-ray-absorption spectra of various condensed organic molecules.

    PubMed

    Schoell, A; Zou, Y; Huebner, D; Urquhart, S G; Schmidt, Th; Fink, R; Umbach, E

    2005-07-22

    We report on a high-resolution C-K and O-K near-edge x-ray-absorption fine-structure (NEXAFS) study of large aromatic molecules in condensed thin films, namely, anhydrides 1,4,5,8-naphthalene-tetracarboxylic acid dianhydride, 3,4,9,10-perylene-tetracarboxylic acid dianhydride, benzoperylene-(1,2)-dicarboxylic acid anhydride, and 1,8-naphthalene-dicarboxylic acid anhydride and the quinoic acenaphthenequinone. Due to the high-energy resolution of the third-generation synchrotron source BESSY II we observe large differences in the NEXAFS fine structures even for very similar molecules, resulting in a wealth of new information. The rich fine structure can unambiguously be assigned to the coupling of electronic transitions to vibronic excitations. Backed by ab initio calculations we present a detailed analysis of the spectra that allows the complete interpretation of the near-edge features. It also yields information on the vibronic properties in the electronically excited state as well as on the response of the electronic system upon core excitation. The strong differences in the electron-vibron coupling for different molecules are discussed. PMID:16095371

  19. High-resolution Submillimeter and Near-infrared Studies of the Transition Disk around Sz 91

    NASA Astrophysics Data System (ADS)

    Tsukagoshi, Takashi; Momose, Munetake; Hashimoto, Jun; Kudo, Tomoyuki; Andrews, Sean; Saito, Masao; Kitamura, Yoshimi; Ohashi, Nagayoshi; Wilner, David; Kawabe, Ryohei; Abe, Lyu; Akiyama, Eiji; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph; Currie, Thayne; Egner, Sebastian E.; Goto, Miwa; Grady, Carol; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko; Henning, Thomas; Hodapp, Klaus W.; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R.; Kusakabe, Nobuhiko; Kuzuhara, Masayuki; Kwon, Jungmi; McElwain, Mike; Matsuo, Taro; Mayama, Satoshi; Miyama, Shoken; Morino, Jun-ichi; Moro-Martín, Amaya; Nishimura, Tetsuro; Pyo, Tae-Soo; Serabyn, Eugene; Suenaga, Takuya; Suto, Hiroshi; Suzuki, Ryuji; Takahashi, Yasuhiro; Takami, Hideki; Takami, Michihiro; Takato, Naruhisa; Terada, Hiroshi; Thalmann, Christian; Tomono, Daigo; Turner, Edwin L.; Usuda, Tomonori; Watanabe, Makoto; Wisniewski, John P.; Yamada, Toru; Tamura, Motohide

    2014-03-01

    To reveal the structures of a transition disk around a young stellar object in Lupus, Sz 91 , we have performed aperture synthesis 345 GHz continuum and CO(3-2) observations with the Submillimeter Array (~1''-3'' resolution) and high-resolution imaging of polarized intensity at the Ks -band using the HiCIAO instrument on the Subaru Telescope (0.''25 resolution). Our observations successfully resolved the inner and outer radii of the dust disk to be 65 and 170 AU, respectively, which indicates that Sz 91 is a transition disk source with one of the largest known inner holes. The model fitting analysis of the spectral energy distribution reveals an H2 mass of 2.4 × 10-3 M ⊙ in the cold (T < 30 K) outer part at 65 AU 3 × 10-9 M ⊙) of hot (T ~ 180 K) dust possibly remains inside the inner hole of the disk. The structure of the hot component could be interpreted as either an unresolved self-luminous companion body (not directly detected in our observations) or a narrow ring inside the inner hole. Significant CO(3-2) emission with a velocity gradient along the major axis of the dust disk is concentrated on the Sz 91 position, suggesting a rotating gas disk with a radius of 420 AU. The Sz 91 disk is possibly a rare disk in an evolutionary stage immediately after the formation of protoplanets because of the large inner hole and the lower disk mass than other transition disks studied thus far.

  20. High-resolution submillimeter and near-infrared studies of the transition disk around Sz 91

    SciTech Connect

    Tsukagoshi, Takashi; Momose, Munetake; Hashimoto, Jun; Kudo, Tomoyuki; Saito, Masao; Ohashi, Nagayoshi; Kawabe, Ryohei; Akiyama, Eiji; Andrews, Sean; Wilner, David; Kitamura, Yoshimi; Abe, Lyu; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph; Currie, Thayne; Egner, Sebastian E.; Guyon, Olivier; Goto, Miwa; Grady, Carol; and others

    2014-03-10

    To reveal the structures of a transition disk around a young stellar object in Lupus, Sz 91 , we have performed aperture synthesis 345 GHz continuum and CO(3-2) observations with the Submillimeter Array (∼1''-3'' resolution) and high-resolution imaging of polarized intensity at the K{sub s} -band using the HiCIAO instrument on the Subaru Telescope (0.''25 resolution). Our observations successfully resolved the inner and outer radii of the dust disk to be 65 and 170 AU, respectively, which indicates that Sz 91 is a transition disk source with one of the largest known inner holes. The model fitting analysis of the spectral energy distribution reveals an H{sub 2} mass of 2.4 × 10{sup –3} M {sub ☉} in the cold (T < 30 K) outer part at 65 AU 3 × 10{sup –9} M {sub ☉}) of hot (T ∼ 180 K) dust possibly remains inside the inner hole of the disk. The structure of the hot component could be interpreted as either an unresolved self-luminous companion body (not directly detected in our observations) or a narrow ring inside the inner hole. Significant CO(3-2) emission with a velocity gradient along the major axis of the dust disk is concentrated on the Sz 91 position, suggesting a rotating gas disk with a radius of 420 AU. The Sz 91 disk is possibly a rare disk in an evolutionary stage immediately after the formation of protoplanets because of the large inner hole and the lower disk mass than other transition disks studied thus far.

  1. HIGH-RESOLUTION FOURIER TRANSFORM SPECTROSCOPY OF LANTHANUM IN Ar DISCHARGE IN THE NEAR-INFRARED

    SciTech Connect

    Güzelçimen, F.; Başar, Gö.; Tamanis, M.; Kruzins, A.; Ferber, R.; Windholz, L.; Kröger, S. E-mail: sophie.kroeger@htw-berlin.de

    2013-10-01

    A high-resolution spectrum of lanthanum has been recorded by a Fourier Transform spectrometer in the wavelength range from 833 nm to 1666 nm (6000 cm{sup –1} to 12,000 cm{sup –1}) using as light source a hollow cathode lamp operated with argon as the discharge carrier gas. In total, 2386 spectral lines were detected in this region, of which 555 lines could be classified as La I transitions and 10 lines as La II transitions. All La II transitions and 534 of these La I transitions were classified for the first time, and 6 of the La II transitions and 433 of the classified La I transitions appear to be new lines, which could not be found in the literature. The corresponding energy level data of classified lines are given. Additionally, 430 lines are assigned as Ar I lines and 394 as Ar II lines, of which 179 and 77, respectively, were classified for the first time. All 77 classified Ar II transitions as well as 159 of the classified Ar I transitions are new lines. Furthermore, the wavenumbers of 997 unclassified spectral lines were determined, 235 of which could be assigned as La lines, because of their hyperfine pattern. The remaining 762 lines may be either unclassified Ar lines or unresolved and unclassified La lines with only one symmetrical peak with an FWHM in the same order of magnitude as the Ar lines. The accuracy of the wavenumber for the classified lines with signal-to-noise-ratio higher than four is better than 0.006 cm{sup –1} which corresponds to an accuracy of 0.0004 nm at 830 nm and 0.0017 nm at 1660 nm, respectively.

  2. Vertical profiling of methane and carbon dioxide using high resolution near-infrared heterodyne spectroscopic observations

    NASA Astrophysics Data System (ADS)

    Rodin, Alexander; Klimchuk, Artem; Churbanov, Dmitry; Pereslavtseva, Anastasia; Spiridonov, Maxim; Nadezhdinskyi, Alexander

    2014-05-01

    We present new method of monitoring greenhouse gases using spectroscopic observations of solar radiation passed through the atmosphere with spectral resolution ΛvδΛ up to 108. Such a high resolution is achieved by heterodyne technique and allows to retrieve full information about spectral line shape which, in turn, is used to distinguish contribution of different atmospheric layers to the resulting absorption. Weak absorption line at 6056.5 cm-1 was selected for CO2 measurements and a quartet of lines centered at 6057 cm-1for CH4. The instrument setup includes Sun tracker with a microtelescope and chopper, diode DFB laser used as a local oscillator, a bundle of single mode optical fibers that provides medium for radiation transfer and beam coupling, reference cell with depressurized methane for LO frequency stabilization, and Fabry-Perot etalon for LO frequency calibration. A commercial p-i-n diode with squared detector replaces a mixer and IF spectrometer, providing measurement of heterodyne beating within a bandpass of few MHz, which determines the effective spectral resolution of the instrument. Spectral coverage within narrow range (about 1 cm-1) is provided by ramping the LO frequency based on feedback from the reference channel. Observations of Sun in the Moscow region have resulted for the first time in measurements of the atmospheric transmission near 1.65 μm with sub-Doppler spectral resolution. In order to retrieve vertical profiles of methane and carbon dioxide we developed the inversion algorithm implementing Tikhonov regularization approach. With measured transmission having S/N ratio of 100 or higher, the uncertainty of CH4 profile is about 10 ppb, with the uncertainty of CO2 profile at 1 ppm. This techniques is promising an affordable opportunity or widespread monitoring of greenhouse gases and may be implemented on existing ground-based stations. This work has been supported by the grant of Russian Ministry of education and science #11.G34.31.0074

  3. River pollution remediation monitored by optical and infrared high-resolution satellite images.

    PubMed

    Trivero, Paolo; Borasi, Maria; Biamino, Walter; Cavagnero, Marco; Rinaudo, Caterina; Bonansea, Matias; Lanfri, Sofia

    2013-09-01

    The Bormida River Basin, located in the northwestern region of Italy, has been strongly contaminated by the ACNA chemical factory. This factory was in operation from 1892 to 1998, and contamination from the factory has had deleterious consequences on the water quality, agriculture, natural ecosystems and human health. Attempts have been made to remediate the site. The aims of this study were to use high-resolution satellite images combined with a classical remote sensing methodology to monitor vegetation conditions along the Bormida River, both upstream and downstream of the ACNA chemical factory site, and to compare the results obtained at different times before and after the remediation process. The trends of the Normalised Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI) along the riverbanks are used to assess the effect of water pollution on vegetation. NDVI and EVI values show that the contamination produced by the ACNA factory had less severe effects in the year 2007, when most of the remediation activities were concluded, than in 2006 and 2003. In 2007, the contamination effects were noticeable up to 6 km downstream of the factory, whereas in 2003 and 2006 the influence range was up to about 12 km downstream of the factory. The results of this study show the effectiveness of remediation activities that have been taking place in this area. In addition, the comparison between NDVI and EVI shows that the EVI is more suitable to characterise the vegetation health and can be considered an additional tool to assess vegetation health and to monitor restoration activities. PMID:23456221

  4. High-Resolution Submillimeter and Near-Infrared Studies of the Transition Disk around Sz 91

    NASA Technical Reports Server (NTRS)

    Tsukagoshi, Takashi; Momose, Munetake; Hashimoto, Jun; Kudo, Tomoyuki; Andrews, Sean; Saito, Masao; Kitamura, Yoshimi; Ohashi, Nagayoshi; Wilner, David; Kawabe, Ryohei; Abe, Lyu; Akiyama, Eiji; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph; Currie, Thayne; Enger, Sebastian E.; Goto, Miwa; Grady, Carol A.; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Henning, Thomas; Hodapp, Klaus W.; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R.; Kusakabe, Nobuhiko; Kuzuhara, Masayuki; Kwon, Jungmi; McElwain, Michael W.; Matsuo, Taro; Mayama, Satoshi

    2014-01-01

    To reveal the structures of a transition disk around a young stellar object in Lupus, Sz 91, we have performed aperture synthesis 345 GHz continuum and CO(32) observations with the Submillimeter Array ( 13 resolution), and high-resolution imaging of polarized intensity at the Ks-band by using the Hi-CIAO instrument on the Subaru Telescope (0.25 resolution). Our observations successfully resolved the inner and outer radii of the dust disk to be 65 and 170AU, respectively, which indicates that Sz 91 is a transition disk source with one of the largest known inner holes. The model fitting analysis of the spectral energy distribution reveals an H2 mass of 2.4 103 M in the cold (T 30 K) outer part at 65 r 170 AU by assuming a canonical gas-to-dust mass ratio of 100, although a small amount ( 3109 M) of hot (T 180 K) dust possibly remains inside the inner hole of the disk. The structure of the hot component could be interpreted as either an unresolved self-luminous companion body (not directly detected in our observations) or a narrow ring inside the inner hole. Significant CO(32) emission with a velocity gradient along the major axis of the dust disk is concentrated on the Sz 91 position, suggesting a rotating gas disk with a radius of 420 AU. The Sz 91 disk is possibly a rare disk in an evolutionary stage immediately after the formation of protoplanets because of the large inner hole and the lower disk mass than other transition disks studied thus far.

  5. High-Resolution Submillimeter and Near-Infrared Studies of the Transition Disk Around Sz 91

    NASA Technical Reports Server (NTRS)

    Tsukagoshi, Takashi; Momose, Munetake; Abe, Lyu; Akiyama, Eiji; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph; Currie, Thayne; Egner, Sebastian E.; Goto, Miwa; Grady, Carol; Guyon, Olivier; Hashimoto, Jun; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko; Henning, Thomas; Hodapp, Klaus W.; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R.; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Kuzuhara, Masayuki; Kwon, Jungmi; McElwain, Mike; Matsuo, Taro; Mayama, Satoshi; Miyama, Shoken; Morino, Jun-ichi; Moro-Martin, Amaya; Nishimura, Tetsuro; Andrews, Sean; Pyo, Tae-Soo; Serabyn, Eugene; Suenaga, Takuya; Suto, Hiroshi; Suzuki, Ryuji; Takahashi, Yasuhiro; Takami, Hideki; Takami, Michihiro; Takato, Naruhisa; Terada, Hiroshi; Saito, Masao; Thalmann, Christian; Tomono, Daigo; Turner, Edwin L.; Usuda, Tomonori; Watanabe, Makoto; Wisniewski, John P.; Yamada, Toru; Tamura, Motohide; Kitamura, Yoshimi; Ohashi, Nagayoshi; Wilner, David; Kawabe, Ryohei

    2014-01-01

    To reveal the structures of a transition disk around a young stellar object in Lupus, Sz 91, we have performed aperture synthesis 345 GHz continuum and CO(3--2) observations with the Submillimeter Array (approximately 1" - 3" resolution), and high-resolution imaging of polarized intensity at the K(sub s) -band by using the HiCIAO instrument on the Subaru Telescope (0.25" resolution). Our observations successfully resolved the inner and outer radii of the dust disk to be 65 AU and 170 AU, respectively, which indicates that Sz 91 is a transition disk source with one of the largest known inner holes. The model fitting analysis of the spectral energy distribution reveals an H 2 mass of 2.4×10(exp -3) M(solar mass) in the cold (T less than 30 K) outer part at 65 less than r less than 170 AU by assuming a canonical gas-to-dust mass ratio of 100, although a small amount (greater than 3×10(exp -9) M(solar mass)) of hot (T approximately 180 K) dust possibly remains inside the inner hole of the disk. The structure of the hot component could be interpreted as either an unresolved self-luminous companion body (not directly detected in our observations) or a narrow ring inside the inner hole. Significant CO(3--2) emission with a velocity gradient along the major axis of the dust disk is concentrated on the Sz 91 position, suggesting a rotating gas disk with a radius of 420 AU. The Sz 91 disk is possibly a rare disk in an evolutionary stage immediately after the formation of protoplanets because of the large inner hole and the lower disk mass than other transition disks studied thus far.

  6. Fourier Transform Infrared Emission Spectra of MgF_2

    NASA Astrophysics Data System (ADS)

    Frohman, Daniel J.; Bernath, Peter F.; Koput, Jacek

    2014-06-01

    High resolution infrared emission spectra of hot MgF2 in the 700 to 1300 cm-1 region have been recorded. The molecules were generated by heating solid MgF2 to 1675 °C. Four vibrational bands were rotationally analyzed yielding band origins and rotational constants. Observed bands are: 001-000 (Σu+ - Σg+), 0111 - 0110 (Πg - Πu), 0221 (f parity) - 0220 (f parity) (Δu - Δg), and 0331 - 0330 (Φg - Φu). High level ab initio calculations were essential in making assignments and in helping to fit the data. The Δu - Δg band was only observed for f-parity because the e-parity is significantly perturbed by l-resonance.

  7. Vibrational infrared and raman spectra of dicyanoacetylene

    NASA Astrophysics Data System (ADS)

    Khanna, R. K.; Perera-Jarmer, M. A.; Ospina, M. J.

    The raman and infrared spectra for solid C 4N 2 are reported. New assignments are given for ˜gn 1 (2333 cm -1), ˜gn 2 (2267) and ˜gn 3 (640 cm -1). These assignments are supported by a normal coordinate Analysis using eight force constants. Extinction coefficients for the infrared active fundamentals are also reported. Our results suggest C 4N 2 to be a likely candidate to explain the 478 cm -1 band in the Titan's emission recorded by the Voyager mission.

  8. A new method to discriminate secondary organic aerosols from different sources using high-resolution aerosol mass spectra

    NASA Astrophysics Data System (ADS)

    Heringa, M. F.; Decarlo, P. F.; Chirico, R.; Tritscher, T.; Clairotte, M.; Mohr, C.; Crippa, M.; Slowik, J. G.; Pfaffenberger, L.; Dommen, J.; Weingartner, E.; Prévôt, A. S. H.; Baltensperger, U.

    2012-02-01

    Organic aerosol (OA) represents a significant and often major fraction of the non-refractory PM1 (particulate matter with an aerodynamic diameter da < 1 μm) mass. Secondary organic aerosol (SOA) is an important contributor to the OA and can be formed from biogenic and anthropogenic precursors. Here we present results from the characterization of SOA produced from the emissions of three different anthropogenic sources. SOA from a log wood burner, a Euro 2 diesel car and a two-stroke Euro 2 scooter were characterized with an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS) and compared to SOA from α-pinene. The emissions were sampled from the chimney/tailpipe by a heated inlet system and filtered before injection into a smog chamber. The gas phase emissions were irradiated by xenon arc lamps to initiate photo-chemistry which led to nucleation and subsequent particle growth by SOA production. Duplicate experiments were performed for each SOA type, with the averaged organic mass spectra showing Pearson's r values >0.94 for the correlations between the four different SOA types after five hours of aging. High-resolution mass spectra (HR-MS) showed that the dominant peaks in the MS, m/z 43 and 44, are dominated by the oxygenated ions C2H3O+ and CO2+, respectively, similarly to the relatively fresh semi-volatile oxygenated OA (SV-OOA) observed in the ambient aerosol. The atomic O:C ratios were found to be in the range of 0.25-0.55 with no major increase during the first five hours of aging. On average, the diesel SOA showed the lowest O:C ratio followed by SOA from wood burning, α-pinene and the scooter emissions. Grouping the fragment ions revealed that the SOA source with the highest O:C ratio had the largest fraction of small ions. The HR data of the four sources could be clustered and separated using principal component analysis (PCA). The model showed a significant separation of the four SOA types and clustering of the duplicate

  9. A new method to discriminate secondary organic aerosols from different sources using high-resolution aerosol mass spectra

    NASA Astrophysics Data System (ADS)

    Heringa, M. F.; Decarlo, P. F.; Chirico, R.; Tritscher, T.; Clairotte, M.; Mohr, C.; Crippa, M.; Slowik, J. G.; Pfaffenberger, L.; Dommen, J.; Weingartner, E.; Prévôt, A. S. H.; Baltensperger, U.

    2011-10-01

    Organic aerosol (OA) represents a significant and often major fraction of the non-refractory PM1 (particulate matter with an aerodynamic diameter da < 1 μm) mass. Secondary organic aerosol (SOA) is an important contributor to the OA and can be formed from biogenic and anthropogenic precursors. Here we present results from the characterization of SOA produced from the emissions of three different anthropogenic sources. SOA from a log wood burner, a Euro 2 diesel car and a two-stroke Euro 2 scooter were characterized with an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS) and compared to SOA from α-pinene. The emissions were sampled from the chimney/tailpipe by a heated inlet system and filtered before injection into a smog chamber. The gas phase emissions were irradiated by xenon arc lamps to initiate photo-chemistry which led to nucleation and subsequent particle growth by SOA production. Duplicate experiments were performed for each SOA type, with the averaged organic mass spectra in the m/z range 12-250 showing Pearson's r values >0.94 for the correlations between the different SOA types after 5 h of aging. High-resolution mass spectra (HR-MS) showed that the dominant peaks in the MS, m/z 43 and 44, are dominated by the oxygenated ions C2H3O+ and CO2+, respectively, similarly to the relatively fresh semi-volatile oxidized OA (SV-OOA) observed in the ambient aerosol. The atomic O : C ratios were found to be in the range of 0.25-0.55 with no major increase during the first 5 h of aging. On average, the diesel SOA showed the lowest O : C ratio followed by SOA from wood burning, α-pinene and the scooter emissions. Grouping the fragment ions based on their carbon number revealed that the SOA source with the highest O : C ratio had the largest fraction of small ions. Fragment ions containing up to 3 carbon atoms accounted for 66%, 68%, 72% and 76% of the organic spectrum of the SOA produced by the diesel car, wood burner, α-pinene and

  10. Packet based serial link realized in FPGA dedicated for high resolution infrared image transmission

    NASA Astrophysics Data System (ADS)

    Bieszczad, Grzegorz

    2015-05-01

    In article the external digital interface specially designed for thermographic camera built in Military University of Technology is described. The aim of article is to illustrate challenges encountered during design process of thermal vision camera especially related to infrared data processing and transmission. Article explains main requirements for interface to transfer Infra-Red or Video digital data and describes the solution which we elaborated based on Low Voltage Differential Signaling (LVDS) physical layer and signaling scheme. Elaborated link for image transmission is built using FPGA integrated circuit with built-in high speed serial transceivers achieving up to 2500Gbps throughput. Image transmission is realized using proprietary packet protocol. Transmission protocol engine was described in VHDL language and tested in FPGA hardware. The link is able to transmit 1280x1024@60Hz 24bit video data using one signal pair. Link was tested to transmit thermal-vision camera picture to remote monitor. Construction of dedicated video link allows to reduce power consumption compared to solutions with ASIC based encoders and decoders realizing video links like DVI or packed based Display Port, with simultaneous reduction of wires needed to establish link to one pair. Article describes functions of modules integrated in FPGA design realizing several functions like: synchronization to video source, video stream packeting, interfacing transceiver module and dynamic clock generation for video standard conversion.

  11. NGC 4102: HIGH-RESOLUTION INFRARED OBSERVATIONS OF A NUCLEAR STARBURST RING

    SciTech Connect

    Beck, Sara C.; Lacy, John H.; Turner, Jean L.

    2010-10-20

    The composite galaxy NGC 4102 hosts a LINER nucleus and a starburst. We mapped NGC 4102 in the 12.8 {mu}m line of [Ne II], using the echelon spectrometer TEXES on the NASA IRTF, to obtain a data cube with 1.''5 spatial, and 25 km s{sup -1} spectral, resolution. Combining near-infrared, radio, and the [Ne II] data shows that the extinction to the starburst is substantial, more than 2 mag at the K band, and that the neon abundance is less than half solar. We find that the star formation in the nuclear region is confined to a rotating ring or disk of 4.''3 ({approx}300 pc) diameter, inside the inner Lindblad resonance. This region is an intense concentration of mass, with a dynamical mass {approx}3 x 10{sup 9} M{sub sun}, and of star formation. The young stars in the ring produce the [Ne II] flux reported by Spitzer for the entire galaxy. The mysterious blue component of line emission detected in the near-infrared is also seen in [Ne II]; it is not a normal active galactic nucleus outflow.

  12. High resolution infrared astronomy satellite observations of a selected spiral galaxy

    NASA Technical Reports Server (NTRS)

    Kulkarni, S. R.

    1991-01-01

    The H I, infrared, CO, H alpha and H beta band observations of M51, the prototypical grand-design spiral galaxy, are used to study the consequences of star formation for the distribution of H I and dust. Using the new Very Large Array (VLA) map of 21 cm emission, the Owens Valley Radio Observatory CO mosaic map, and an H alpha imate, new tests were performed with the idea of Tilanus and Allen that the H I is largely a photodissociation product in star-forming regions. It is confirmed that the H I spiral arms are generally coincident with the H II region arms, and offset downstream from the CO arms. The radial distributions of total gas, H alpha and H I surface density have a simple explanation in the dissociation picture. The distributions also demonstrate how the surface density of H I might be related to the star formation efficiency in molecule-rich galaxies. The large width of the H I regions along the arms compared to that of the giant H II regions can be understood in terms of a simple calculation of the expected size of an H I region associated with a typical giant H II region. The longer lifetime of the stars producing dissociating radiation vs. those producing ionizing radiation and the relatively long molecular formation timescale will also contribute to the greater width of the H I arms if stars are continuously forming on the arms. The lack of detailed coincidence of the H I and H II regions along the inner arms has a variety of possible explanations. Two simple tests were performed to probe the origins of the IRAS emission in M51. First, it was found that the infrared excess (IFE) of M51 is 24, suggesting that a substantial fraction of the infrared emission arises from dust heated by photons which do not originate in massive star-formaing regions. Second, radial cuts through the IRAS bands show that at 12, 25, and 60 microns, the arm-interarm contrast of the IRAS emission is substantially less than that of the H alpha emission, providing further

  13. Ab initio infrared and Raman spectra

    NASA Technical Reports Server (NTRS)

    Fredkin, D. R.; White, S. R.; Wilson, K. R.; Komornicki, A.

    1983-01-01

    It is pointed out that with increased computer power and improved computational techniques, such as the gradients developed in recent years, it is becoming practical to compute spectra ab initio, from the fundamental constants of nature, for systems of increasing complexity. The present investigation has the objective to explore several possible ab initio approaches to spectra, giving particular attention to infrared and nonresonance Raman. Two approaches are discussed. The sequential approach, in which first the electronic part and then later the nuclear part of the Born-Oppenheimer approximation is solved, is appropriate for small systems. The simultaneous approach, in which the electronic and nuclear parts are solved at the same time, is more appropriate for many-atom systems. A review of the newer quantum gradient techniques is provided, and the infrared and Raman spectral band contours for the water molecule are computed.

  14. High-Resolution Optical and Near-Infrared Imaging of Young Circumstellar Disks

    NASA Technical Reports Server (NTRS)

    McCaughrean, Mark; Stapelfeldt, Karl; Close, Laird

    2000-01-01

    In the past five years, observations at optical and near-infrared wavelengths obtained with the Hubble Space Telescope and ground-based adaptive optics have provided the first well-resolved images of young circumstellar disks which may form planetary systems. We review these two observational techniques and highlight their results by presenting prototype examples of disks imaged in the Taurus-Auriga and Orion star-forming regions. As appropriate, we discuss the disk parameters that may be typically derived from the observations, as well as the implications that the observations may have on our understanding of, for example, the role of the ambient environment in shaping the disk evolution. We end with a brief summary of the prospects for future improvements in space- and ground-based optical/IR imaging techniques, and how they may impact disk studies.

  15. High resolution infrared spectroscopy of planetary molecules using diode lasers and Fourier transform spectrometers

    NASA Technical Reports Server (NTRS)

    Jennings, Donald E.

    1990-01-01

    Modern observations of infrared molecular lines in planets are performed at spectral resolutions which are as high as those available in the laboratory. Analysis of such data requires laboratory measurements at the highest possible resolution, which also yield accurate line positions and intensities. For planetary purposes the spectrometer must be coupled to sample cells which can be reduced in temperature and varied in pressure. An approach which produces the full range of required molecular line parameters uses a combination of tunable diode lasers and Fourier transform spectrometers (FTS). The FTS provides board spectral coverage and good calibration accuracy, while the diode laser can be used to study those regions which are not resolved by the FTS.

  16. Water ingress detection in honeycomb sandwich panels by passive infrared thermography using a high-resolution thermal imaging camera

    NASA Astrophysics Data System (ADS)

    Ibarra-Castanedo, C.; Brault, L.; Marcotte, F.; Genest, M.; Farley, V.; Maldague, X.

    2012-06-01

    Water ingress in honeycomb structures is of great concern for the civil and military aerospace industries. Pressure and temperature variations during take-off and landing produce considerable stress on aircraft structures, promoting moisture ingress (by diffusion through fibers or by direct ingress through voids, cracks or unsealed joints) into the core. The presence of water (or other fluids such as kerosene, hydraulic fluid and de-icing agents) in any of its forms (gas vapor, liquid or ice) promotes corrosion, cell breakage, and induce composite layer delaminations and skin disbonds. In this study, testing specimens were produced from unserviceable parts from military aircraft. In order to simulate atmospheric conditions during landing, selected core areas were filled with measured quantities of water and then frozen in a cold chamber. The specimens were then removed from the chamber and monitored for over 20 minutes as they warm up using a cooled high-resolution infrared camera. Results have shown that detection and quantification of water ingress on honeycomb sandwich structures by passive infrared thermography is possible using a HD mid-wave infrared cameras for volumes of water as low as 0.2 ml and from a distance as far as 20 m from the target.

  17. High-Resolution Pyrimidine- and Ribose-Specific 4D HCCH-COSY Spectra of RNA Using the Filter Diagonalization Method

    PubMed Central

    Douglas, Justin T.; Latham, Michael P.; Armstrong, Geoffrey S.; Bendiak, Brad; Pardi, Arthur

    2010-01-01

    NMR spectra of nucleic acids suffer from severe peak overlap, which complicates resonance assignments. 4D NMR experiments can overcome much of the degeneracy in 2D and 3D spectra; however, the linear increase in acquisition time with each new dimension makes it impractical to acquire high-resolution 4D spectra using standard Fourier Transform (FT) techniques. The Filter Diagonalization Method (FDM) is a numerically efficient algorithm that fits the entire multi-dimensional time-domain data to a set of multi-dimensional oscillators. Selective 4D constant-time HCCH-COSY experiments that correlate the H5-C5-C6-H6 base spin systems of pyrimidines or the H1′-C1′-C2′-H2′ spin systems of ribose sugars were acquired on the 13C-labeled Iron Responsive Element RNA. FDM-processing of these 4D experiments recorded with only 8 complex points in the indirect dimensions showed superior spectral resolution than FT-processed spectra. Practical aspects of obtaining optimal FDM-processed spectra are discussed. The results here demonstrate that FDM-processing can be used to obtain high-resolution 4D spectra on a medium sized RNA in a fraction of the acquisition time normally required for high-resolution, high-dimensional spectra. PMID:18626775

  18. Development of a near-infrared high-resolution spectrograph (WINERED) for a survey of bulge stars

    NASA Astrophysics Data System (ADS)

    Tsujimoto, T.; Kobayashi, N.; Yasui, C.; Kondo, S.; Minami, A.; Motohara, K.; Ikeda, Y.; Gouda, N.

    2008-07-01

    We are developing a new near-infrared high-resolution (R[max] = 100,000) and high-sensitive spectrograph WINERED, which is specifically customized for short NIR bands at 0.9 1.35 μm. WINERED employs an innovative optical system; a portable design and a warm optics without any cold stops. The planned astrometric space mission JASMINE will provide precise positions, distances, and proper motions of the bulge stars. The missing components, the radial velocity and chemical composition will be measured by WINERED. These combined data brought by JASMINE and WINERED will certainly reveal the nature of the Galactic bulge. We plan to complete this instrument for observations of single objects by the end of 2008 and to attach it to various 4 10m telescopes as a PI-type instrument. We hope to upgrade WINERED with a multi-object feed in the future for efficient survey of the JASMINE bulge stars.

  19. High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption of Redoubt Volcano, Alaska

    USGS Publications Warehouse

    Wessels, Rick L.; Vaughan, R. Greg; Patrick, Matthew R.; Coombs, Michelle L.

    2013-01-01

    A combination of satellite and airborne high-resolution visible and thermal infrared (TIR) image data detected and measured changes at Redoubt Volcano during the 2008–2009 unrest and eruption. The TIR sensors detected persistent elevated temperatures at summit ice-melt holes as seismicity and gas emissions increased in late 2008 to March 2009. A phreatic explosion on 15 March was followed by more than 19 magmatic explosive events from 23 March to 4 April that produced high-altitude ash clouds and large lahars. Two (or three) lava domes extruded and were destroyed between 23 March and 4 April. After 4 April, the eruption extruded a large lava dome that continued to grow until at least early July 2009.

  20. High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption at Redoubt Volcano, Alaska

    NASA Astrophysics Data System (ADS)

    Wessels, Rick L.; Vaughan, R. Greg; Patrick, Matthew R.; Coombs, Michelle L.

    2013-06-01

    A combination of satellite and airborne high-resolution visible and thermal infrared (TIR) image data detected and measured changes at Redoubt Volcano during the 2008-2009 unrest and eruption. The TIR sensors detected persistent elevated temperatures at summit ice-melt holes as seismicity and gas emissions increased in late 2008 to March 2009. A phreatic explosion on 15 March was followed by more than 19 magmatic explosive events from 23 March to 4 April that produced high-altitude ash clouds and large lahars. Two (or three) lava domes extruded and were destroyed between 23 March and 4 April. After 4 April, the eruption extruded a large lava dome that continued to grow until at least early July 2009.

  1. The spectral and spatial distribution of radiation from Eta Carinae. II High-resolution infrared maps of the Homunculus

    NASA Technical Reports Server (NTRS)

    Hyland, A. R.; Robinson, G.; Mitchell, R. M.; Thomas, J. A.; Becklin, E. E.

    1979-01-01

    The spectral and spatial distribution of radiation from Eta Carinae II and high-resolution infrared maps of the Homunculus are presented. It is found that at the resolution of 1.1 arcsec the source is resolved into two intensity peaks at four wavelengths from 3.6 to 11.2 microns. The separation of the two peaks with wavelength is discussed, concluding that they are produced by an asymmetrical distribution of dust formed by extensive mass loss from the central source. The extension of the wings of the source at various wavelengths provide confirmatory evidence for an enrichment of a grain species such as corundum, relative to silicate material in the outer regions of the source.

  2. Application of high-resolution thermal infrared sensors for geothermal exploration at the Salton Sea, California

    NASA Astrophysics Data System (ADS)

    Reath, K. A.; Ramsey, M.; Tratt, D. M.

    2010-12-01

    The Salton Sea geothermal field straddles the southeast margin of the Salton Sea in California, USA. This field includes approximately 20km2 of mud volcanoes and mud pots and centered on the Mullet Island thermal anomaly. The area has been previously exploited for geothermal power; there are currently seven power plants in the area that produce 1000 MW. The field itself is relatively un-vegetated, which provides for unfettered detection of the surface mineralogy, radiant heat, and emitted gases using air and spaceborne thermal infrared (TIR) sensors. On March 26, 2009, the airborne Spatially Enhanced Broadband Array Spectrograph System (SEBASS) sensor was flown over the Salton Sea-Mullet Island area. SEBASS has a spectral resolution of 128 bands in the 7.5-14.5 micron spectral region and a spatial resolution of 1m/pixel from the 3000-ft altitude flown for this study. A large portion of the Calipatria Fault, a NW/SE-trending geothermally active fault that bisects the Mullet Island thermal anomaly, was imaged during this flight and several thermal/mineralogical anomalies were noted. The orbital Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) has only 5 spectral bands at 90m/pixel resolution, but has acquired dozens of visible and TIR datasets over the geothermal field in the 10-year history of the instrument. The thermal-temporal trend of this dataset has been analyzed, and the November 2008 image studied in detail for comparison to SEBASS. The land-leaving TIR radiance data were separated into brightness temperature and surface emissivity. TIR emissivity data are unique to each mineral and a TIR mineral spectral library was used to determine their presence on the ground. Various mineral maps were created showing the distribution surrounding the most active geothermal features. The higher spectral/spatial resolution SEBASS data were used to validate the lower spectral/spatial resolution ASTER data (as well as the higher resolution laboratory TIR

  3. Spartan infrared camera: high-resolution imaging for the SOAR Telescope

    NASA Astrophysics Data System (ADS)

    Loh, Edwin D.; Biel, Jason D.; Chen, Jian-Jun; Davis, Michael; Laporte, Rene; Loh, Owen Y.

    2004-09-01

    The Spartan Infrared Camera provides tip-tilt corrected imaging for the SOAR Telescope in the 1-2.5μm spectral range with four 2048x2048 HAWAII2 detectors. The median image size is expected to be less than 0.25 arcsec (FWHM), and in the H and K bands a significant amount of the light is expected to be in a core having the diffraction-limited width. The camera has two plate scales: 0.04 arcsec/pixel (f/21) for diffraction-limited sampling in the H and K bands and 0.07 arcsec/pixel (f/12) to cover a 5×5 arcmin2 field, over which tip-tilt correction is substantial. Except for CaF2 field-flattening lenses, the optics is all reflective to achieve the large field size and achromaticity, and all aluminum to match thermally the aluminum cryogenic-optical box in which the optics mount. The Strehl ratio of the camera itself is 0.95-1.00 for the f/21 channel. The optics (including the off-axis aspherical mirrors) will be aligned with precise metrology rather than adjusted using interferometry.

  4. High-Resolution Near-Infrared Polarimetry of a Circumstellar Disk around UX Tau A

    NASA Technical Reports Server (NTRS)

    Serabyn, G.; Grady, C. A.; Currie, T.

    2012-01-01

    We present H-band polarimetric imagery of UX Tau A taken with HiCIAO/AO188 on the Subaru Telescope. UX Tau A has been classified as a pre-transitional disk object, with a gap structure separating its inner and outer disks. Our imagery taken with the 0.15" (21 AU) radius coronagraphic mask has revealed a strongly polarized circumstellar disk surrounding UX Tau A which extends to 120 AU, at a spatial resolution of 0.1" (14 AU). It is inclined by 46 degrees plus or minus 2 degrees as the west side is nearest. Although SED modeling and sub-millimeter imagery suggested the presence of a gap in the disk, with the inner edge of the outer disk estimated to be located at 25 - 30 AU, we detect no evidence of a gap at the limit of our inner working angle (23AU) at the near-infrared wavelength. We attribute the observed strong polarization (up to 66 %) to light scattering by dust grains in the disk. However, neither polarization models of the circumstellar disk based on Rayleigh scattering nor Mie scattering approximations were consistent with the observed azimuthal profile of the polarization degrees of the disk. Instead, a geometric optics model of the disk with nonspherical grains with the radii of 30 micrometers is consistent with the observed profile. We suggest that the dust grains have experienced frequent collisional coagulations and have grown in the circumstellar disk of UX Tau A.

  5. High-resolution subtyping of Staphylococcus aureus strains by means of Fourier-transform infrared spectroscopy.

    PubMed

    Johler, Sophia; Stephan, Roger; Althaus, Denise; Ehling-Schulz, Monika; Grunert, Tom

    2016-05-01

    Staphylococcus aureus causes a variety of serious illnesses in humans and animals. Subtyping of S. aureus isolates plays a crucial role in epidemiological investigations. Metabolic fingerprinting by Fourier-transform infrared (FTIR) spectroscopy is commonly used to identify microbes at species as well as subspecies level. In this study, we aimed to assess the suitability of FTIR spectroscopy as a tool for S. aureus subtyping. To this end, we compared the subtyping performance of FTIR spectroscopy to other subtyping methods such as pulsed field gel electrophoresis (PFGE) and spa typing in a blinded experimental setup and investigated the ability of FTIR spectroscopy for identifying S. aureus clonal complexes (CC). A total of 70 S. aureus strains from human, animal, and food sources were selected, for which clonal complexes and a unique virulence and resistance gene pattern had been determined by DNA microarray analysis. FTIR spectral analysis resulted in high discriminatory power similar as obtained by spa typing and PFGE. High directional concordance was found between FTIR spectroscopy based subtypes and capsular polysaccharide expression detected by FTIR spectroscopy and the cap specific locus, reflecting strain specific expression of capsular polysaccharides and/or other surface glycopolymers, such as wall teichoic acid, peptidoglycane, and lipoteichoic acid. Supervised chemometrics showed only limited possibilities for differentiation of S. aureus CC by FTIR spectroscopy with the exception of CC45 and CC705. In conclusion, FTIR spectroscopy represents a valuable tool for S. aureus subtyping, which complements current molecular and proteomic strain typing. PMID:27021524

  6. High resolution far-infrared observations of the evolved H II region M16

    SciTech Connect

    McBreen, B.; Fazio, G.G.; Jaffe, D.T.

    1982-03-01

    M16 is an evolved, extremely density bounded H II region, which now consists only of a series of ionization fronts at molecular cloud boundaries. The source of ionization is the OB star cluster (NGC 6611) which is about 5 x 10/sup 6/ years old. We used the CFA/UA 102 cm balloon-borne telescope to map this region and detected three far-infrared (far-IR) sources embedded in an extended ridge of emission. Source I is an unresolved far-IR source embedded in a molecular cloud near a sharp ionization front. An H/sub 2/O maser is associated with this source, but no radio continuum emission has been observed. The other two far-IR sources (II and III) are associated with ionized gas-molecular cloud interfaces, with the far-IR radiation arising from dust at the boundary heated by the OB cluster. Source II is located at the southern prominent neutral intrusion with its associated bright rims and dark ''elephant trunk'' globules that delineate the current progress of the ionization front into the neutral material, and Source III arises at the interface of the northern molecular cloud fragment.

  7. High-resolution atmospheric pressure infrared laser desorption/ionization mass spectrometry imaging of biological tissue.

    PubMed

    Römpp, Andreas; Schäfer, Karl Christian; Guenther, Sabine; Wang, Zheng; Köstler, Martin; Leisner, Arne; Paschke, Carmen; Schramm, Thorsten; Spengler, Bernhard

    2013-09-01

    An atmospheric pressure laser desorption/ionization mass spectrometry imaging ion source has been developed that combines high spatial resolution and high mass resolution for the in situ analysis of biological tissue. The system is based on an infrared laser system working at 2.94 to 3.10 μm wavelength, employing a Nd:YAG laser-pumped optical parametrical oscillator. A Raman-shifted Nd:YAG laser system was also tested as an alternative irradiation source. A dedicated optical setup was used to focus the laser beam, coaxially with the ion optical axis and normal to the sample surface, to a spot size of 30 μm in diameter. No additional matrix was needed for laser desorption/ionization. A cooling stage was developed to reduce evaporation of physiological cell water. Ions were formed under atmospheric pressure and transferred by an extended heated capillary into the atmospheric pressure inlet of an orbital trapping mass spectrometer. Various phospholipid compounds were detected, identified, and imaged at a pixel resolution of up to 25 μm from mouse brain tissue sections. Mass accuracies of better than 2 ppm and a mass resolution of 30,000 at m/z = 400 were achieved for these measurements. PMID:23877173

  8. High-Resolution Infrared Imaging of FSC 10214+4724: Evidence for Gravitational Lensing

    NASA Astrophysics Data System (ADS)

    Graham, James R.; Liu, Michael C.

    1995-08-01

    We present near-infrared observations of the ultraluminous high-redshift (z = 2.286) IRAS source FSC 10214+4724 obtained in 0."4 seeing at the W. M. Keck telescope. These observations show that FSC 10214+4724 consists of a highly symmetric circular arc centered on a second weaker source. The arc has an angular extent of about 140 deg and is probably unresolved in the transverse direction. This morphology constitutes compelling prima facie evidence for a gravitationally lensed system. Our images also contain evidence for the faint counterimage predicted by the lens hypothesis. The morphology of FSC 10214+4724 can be explained in terms of a gravitationally lensed background source if the object at the center of curvature of the arc is an L* galaxy at z ~ 0.7. If FSC 10214+4724 is lensed, then there is significant magnification and its luminosity has been overestimated by a large factor. Our results suggest that FSC 10214+4724 is not a uniquely luminous object but ranks among the most powerful quasars and ultraluminous IRAS galaxies.

  9. HIGH-RESOLUTION 1.6 {mu}m SPECTRA OF FeH IN M AND L DWARFS {sup ,}

    SciTech Connect

    Hargreaves, Robert J.; Bernath, Peter F.; Hinkle, Kenneth H.; Bauschlicher, Charles W.; Wende, Sebastian; Seifahrt, Andreas E-mail: pfb500@york.ac.u E-mail: Charles.W.Bauschlicher@nasa.go E-mail: seifahrt@physics.ucdavis.ed

    2010-10-15

    Near-infrared bands due to the iron monohydride (FeH) molecule are a characteristic feature of late-M and -L dwarfs. We have created a line list at 2200 K for the FeH E {sup 4{Pi}}-A {sup 4{Pi}} electronic transition near 1.58 {mu}m (6300 cm{sup -1}) based on laboratory spectra and an ab initio calculation of the band strength. A variety of M and L dwarfs were observed near 1.6 {mu}m with high spectral resolution (R {approx} 70,000) using the Phoenix spectrograph on the 8.1 m Gemini South telescope. The FeH E-A transition made a surprisingly strong contribution to the observed spectral energy distributions and needs to be included in modeling of late-M and L dwarfs.

  10. High Resolution Infrared Spectroscopy and Semi-Experimental Structures of Si2C3 and Ge2C3

    NASA Astrophysics Data System (ADS)

    Lutter, Volker; Giesen, Thomas; Gauss, Jürgen; Thorwirth, Sven

    2014-06-01

    Molecular species of group 14 elements e.g. carbon, silicon, and germanium are well suited to study cumulenic bond properties and to compare experimental results with high level quantum chemical calculations. In our recent investigation of SiC_3Si and GeC_3Ge, a high resolution laser spectrometer has been used to record rotationally resolved spectra of selected isotopologues at 5 μm. We derived semi-empirical values for Si-C and Ge-C bond distances based on spectroscopic data and corresponding zero-point vibrational corrections calculated at the CCSD(T)/cc-pVXZ level of theory (with X = T and Q). Comparison of semi-empirical structural parameters with those from quantum chemical calculations reveals very good agreement for both molecules. Relativistic effects are found negligible for SiC_3Si and small for GeC_3Ge.

  11. Infrared spectroscopy of ruthenium tetroxide and high-resolution analysis of the ν3 band

    NASA Astrophysics Data System (ADS)

    Reymond-Laruinaz, S.; Boudon, V.; Manceron, L.; Lago, L.; Doizi, D.

    2015-09-01

    RuO4 is a heavy tetrahedral molecule which has practical uses for several industrial fields. Due to its chemical toxicity and the radiological impact of its 103 and 106 isotopologues, the possible remote sensing of this compound in the atmosphere has renewed interest in its spectroscopic properties. New, higher resolution FTIR spectra have been recorded at room temperature, using an isotopic pure sample of 102RuO4 and a sample with all stable isotopes present in natural abundance. We reinvestigate here the strong ν3 stretching fundamental region and perform new assignments and effective Hamiltonian parameter fits for the five main isotopologues (99RuO4, 100RuO4, 101RuO4, 102RuO4 and 104RuO4), by considering the ν3 stretching mode as an isolated band. We provide precise effective Hamiltonian parameters, including band centers and Coriolis interaction parameters. We discuss isotopic shifts and estimate the band centers for the two minor isotopologues (97RuO4 and 98RuO4) and the two radioactive isotopologues (103RuO4 and 106RuO4). Experimental band strengths for the two IR active fundamentals are also reported for the first time.

  12. Factor analysis of combined organic and inorganic aerosol mass spectra from high resolution aerosol mass spectrometer measurements

    NASA Astrophysics Data System (ADS)

    Sun, Y. L.; Zhang, Q.; Schwab, J. J.; Yang, T.; Ng, N. L.; Demerjian, K. L.

    2012-05-01

    The high resolution mass spectra of organic and inorganic aerosols from aerosol mass spectrometer (AMS) measurements were first combined into positive matrix factorization (PMF) analysis to investigate the sources and evolution processes of atmospheric aerosols. The new approach is able to study the mixing of organic aerosols (OA) and inorganic species, the acidity of OA factors, and the fragment ion patterns related to photochemical processing. In this study, PMF analysis of the unified AMS spectral matrices resolved 8 factors for the submicron aerosols measured at Queens College in New York City in summer 2009. The hydrocarbon-like OA (HOA) and cooking OA (COA) contain very minor inorganic species, indicating the different sources and mixing characteristics between primary OA and secondary species. The two factors that are primarily ammonium sulfate (SO4-OA) and ammonium nitrate (NO3-OA), respectively, are overall neutralized, of which the OA in SO4-OA shows the highest oxidation state (O/C = 0.69) among OA factors. The semi-volatile oxygenated OA comprises two components, i.e., a less oxidized (LO-OOA) and a more oxidized (MO-OOA). The MO-OOA represents a local photochemical product with the diurnal profile exhibiting a pronounced noon peak, consistent with those of formaldehyde (HCHO) and Ox (= O3+NO2). The much higher NO+/NO2+ fragment ion ratio in MO-OOA than that from ammonium nitrate alone provides evidence for the formation of organic nitrates. The amine-related nitrogen-enriched OA (NOA) contains ~25% of acidic inorganic salts, elucidating the formation of secondary OA from amines in acidic environments. The size distributions derived from 3-dimensional size-resolved mass spectra show distinct diurnal evolving behaviors for different OA factors, but overall a progressing evolution from smaller to larger particle mode as a function of oxidation states. Our results demonstrate that PMF analysis by incorporating inorganic aerosols is of importance for

  13. Factor analysis of combined organic and inorganic aerosol mass spectra from high resolution aerosol mass spectrometer measurements

    NASA Astrophysics Data System (ADS)

    Sun, Y. L.; Zhang, Q.; Schwab, J. J.; Yang, T.; Ng, N. L.; Demerjian, K. L.

    2012-09-01

    Positive matrix factorization (PMF) was applied to the merged high resolution mass spectra of organic and inorganic aerosols from aerosol mass spectrometer (AMS) measurements to investigate the sources and evolution processes of submicron aerosols in New York City in summer 2009. This new approach is able to study the distribution of organic and inorganic species in different types of aerosols, the acidity of organic aerosol (OA) factors, and the fragment ion patterns related to photochemical processing. In this study, PMF analysis of the unified AMS spectral matrix resolved 8 factors. The hydrocarbon-like OA (HOA) and cooking OA (COA) factors contain negligible amounts of inorganic species. The two factors that are primarily ammonium sulfate (SO4-OA) and ammonium nitrate (NO3-OA), respectively, are overall neutralized. Among all OA factors the organic fraction of SO4-OA shows the highest degree of oxidation (O/C = 0.69). Two semi-volatile oxygenated OA (OOA) factors, i.e., a less oxidized (LO-OOA) and a more oxidized (MO-OOA), were also identified. MO-OOA represents local photochemical products with a diurnal profile exhibiting a pronounced noon peak, consistent with those of formaldehyde (HCHO) and Ox(= O3 + NO2). The NO+/NO2+ ion ratio in MO-OOA is much higher than that in NO3-OA and in pure ammonium nitrate, indicating the formation of organic nitrates. The nitrogen-enriched OA (NOA) factor contains ~25% of acidic inorganic salts, suggesting the formation of secondary OA via acid-base reactions of amines. The size distributions of OA factors derived from the size-resolved mass spectra show distinct diurnal evolving behaviors but overall a progressing evolution from smaller to larger particle mode as the oxidation degree of OA increases. Our results demonstrate that PMF analysis of the unified aerosol mass spectral matrix which contains both inorganic and organic aerosol signals may enable the deconvolution of more OA factors and gain more insights into the

  14. Synthetic Solar Spectra Out Of Atmos Data For The Near- And Mid-infrared Ranges

    NASA Astrophysics Data System (ADS)

    Seo, Haing Ja; Kim, S.; Kim, J.; Jang, M.

    2006-09-01

    We have constructed synthetic solar spectra for the 2.5 - 3.0 μm, 4.1 - 4.4 μm, and 5.1 - 7.7 μm ranges using Voigt line profiles, and with solar line identifications compiled by Geller (1992), who derived solar line positions and intensities from contaminated high-resolution solar spectra obtained by ATMOS (Atmospheric Trace Molecule Spectroscopy), a spaceborne observatory. Because the ATMOS spectra in these wavelength ranges are contaminated by absorption lines of molecules existing in Earth's high-altitude atmosphere, the direct use of this high-resolution solar spectra has been inconvenient for planetary scientists. We compared the synthetic solar spectra with the ATMOS spectra, and obtained satisfactory fits with the exception of a few abnormal lines. From the satisfactory comparisons, we were able to determine Voigt line parameters for each solar line. These synthetic solar spectra will be useful to eliminate solar continua from spectra of planetary objects to extract their own spectral characteristics. Reference Geller, M., 1992, A High-Resolution Atlas of the Infrared Spectrum of the Sun and the Earth Atmosphere from Space, Vol. III. Key to Identification of Solar Features, NASA Reference Pub. 1224.

  15. Mid-Infrared OPO for High Resolution Measurements of Trace Gases in the Mars Atmosphere

    NASA Technical Reports Server (NTRS)

    Yu, Anthony W.; Numata,Kenji; Riris, haris; Abshire, James B.; Allan, Graham; Sun, Xiaoli; Krainak, Michael A.

    2008-01-01

    The Martian atmosphere is composed primarily (>95%) of CO2 and N2 gas, with CO, O2, CH4, and inert gases such as argon comprising most of the remainder. It is surprisingly dynamic with various processes driving changes in the distribution of CO2, dust, haze, clouds and water vapor on global scales in the meteorology of Mars atmosphere [I]. The trace gases and isotopic ratios in the atmosphere offer important but subtle clues as to the origins of the planet's atmosphere, hydrology, geology, and potential for biology. In the search for life on Mars, an important process is the ability of bacteria to metabolize inorganic substrates (H2, CO2 and rock) to derive energy and produce methane as a by-product of anaerobic metabolism. Trace gases have been measured in the Mars atmosphere from Earth, Mars orbit, and from the Mars surface. The concentration of water vapor and various carbon-based trace gases are observed in variable concentrations. Within the past decade multiple groups have reported detection of CH4, with concentrations in the 10's of ppb, using spectroscopic observations from Earth [2]. Passive spectrometers in the mid-infrared (MIR) are restricted to the sunlit side of the planet, generally in the mid latitudes, and have limited spectral and spatial resolution. To accurately map the global distribution and to locate areas of possibly higher concentrations of these gases such as plumes or vents requires an instrument with high sensitivity and fine spatial resolution that also has global coverage and can measure during both day and night. Our development goal is a new MIR lidar capable of measuring, on global scales, with sensitivity, resolution and precision needed to characterize the trace gases and isotopic ratios of the Martian atmosphere. An optical parametric oscillator operating in the MIR is well suited for this instrument. The sufficient wavelength tuning range of the OPO can extend the measurements to other organic molecules, CO2, atmospheric water

  16. [Infrared and Raman spectra study on Tianhuang].

    PubMed

    Liu, Yun-gui; Chen, Tao

    2012-08-01

    The Tianhuang stones, from Shoushan in China, were studied by using X-ray powder diffractometry (XRD), infrared (IR) spectroscopy and Raman spectroscopy to obtain the spectra characterization. Wave numbers 3621, 3629 and 3631 cm(-1) in the IR spectra and 3626, 3627 and 3632 cm(-1) in the Raman spectra are the characteristic peaks of dickitic Tianhuang, nacritic Tianhuang and illitic Tianhuang, respectively. Raman spectra assigned to OH are in good agreement with the IR results at 3550 -3750 cm(-1). Dickitic Tianhuang includes ordered dickite and disordered dickite. Compared with ordered dickite, the band assigned to OH3 of disordered dickite shifts to low-frequency by 8 cm(-1) and the relative intensity becomes stronger. The disorder structure may relate to the high level of Fe. The IR absorption spectra of nacritic Tianhuang superimposes strong peaks of dickite, indicating that IR absorption bands of dickite are stronger than that of nacrite at 3550-3750 cm(-1). The main mineral composition of illitic Tianhuang is 2M(1), while illite Tianhuang contains a small amount of 1M. All these characters provide a theoretical basis for the scientific identification of Tianhuang. PMID:23156769

  17. A High Resolution, Unobscured View of the Active Regions in (Ultra) Luminous Infrared Galaxies from a VLA 33 GHz Survey

    NASA Astrophysics Data System (ADS)

    Barcos-Muñoz, L.; Leroy, A.; Evans, A.; et al.

    2016-06-01

    I will present a new survey of 33 GHz radio continuum emission from local U/LIRGs carried out using the Karl G. Jansky Very Large Array (VLA). This is the first such survey and it combines high resolution, good sensitivity, and multi-configuration observations that should have sensitivity to emission on all spatial scales. (Ultra) luminous infrared galaxies host some of the most extreme star-forming environments in the local universe, with large reservoirs of molecular gas and dust concentrated in the central few kpc. Our VLA observations allow us to see through the dust in these systems to resolve the sizes of their active regions, which is essential to understand the surface and volume densities of star formation and gas in these extreme systems. I will present the best size measurements to date of the active regions for our 22 targets. I will show what these sizes imply about gas volume and surface density and infrared luminosity surface densities. I will also lay out the physical implications of these values for the strength of star formation and feedback (especially radiative feedback) in extreme environments.

  18. High-Resolution Infrared Spectrum of the ν_3+ν_8 Combination Band of Jet-Cooled Propyne

    NASA Astrophysics Data System (ADS)

    Zhao, Dongfeng; Linnartz, Harold

    2014-06-01

    Propyne (CH3-C≡CH) is an important molecule in astrophysics and planetary atmospheres, and an important constituent of fuels. Spectroscopic investigation of propyne is also of fundamental interest in intramolecular vibrational redistribution (IVR) dynamics of hydrocarbons. Although extensive spectroscopic studies on this simple organic molecule have been performed, the ν_3+ν_8 band has not been reported before. In this presentation, the high-resolution infrared spectrum of the ν_3+ν_8 combination band of propyne is presented. Continuous-wave cavity ring-down spectroscopy is used to measure this weak infrared band in the 3175 cm-1 region using a supersonic free jet. The rotational analysis of the experimental spectrum results in accurate spectroscopic parameters for the ν_3+ν_8 combination vibrational state. Severe perturbations are found for K = 3 and 4 rotational levels, and are likely due to near-resonant or non-resonant interactions between the ν_3+ν_8 and other vibrational states. Moreover, three parallel-transition type subbands are observed and their analysis is presented as well. D. Zhao, H. Linnartz, Chem. Phys. Lett. (2014), DOI: 10.1016/j.cplett.2014.02.016.

  19. A detailed analysis of the high-resolution X-ray spectra of NGC 3516: variability of the ionized absorbers

    SciTech Connect

    Huerta, E. M.; Krongold, Y.; Jimenez-Bailon, E.; Nicastro, F.; Mathur, S.; Longinotti, A. L.

    2014-09-20

    The 1.5 Seyfert galaxy NGC 3516 presents a strong time variability in X-rays. We re-analyzed the nine observations performed in 2006 October by XMM-Newton and Chandra in the 0.3 to 10 keV energy band. An acceptable model was found for the XMM-Newton data fitting the EPIC-PN and RGS spectra simultaneously; later, this model was successfully applied to the contemporary Chandra high-resolution data. The model consists of a continuum emission component (power law + blackbody) absorbed by four ionized components (warm absorbers), and 10 narrow emission lines. Three absorbing components are warm, producing features only in the soft X-ray band. The fourth ionization component produces Fe XXV and Fe XXVI in the hard-energy band. We study the time response of the absorbing components to the well-detected changes in the X-ray luminosity of this source and find that the two components with the lower ionization state show clear opacity changes consistent with gas close to photoionization equilibrium. These changes are supported by the models and by differences in the spectral features among the nine observations. On the other hand, the two components with higher ionization state do not seem to respond to continuum variations. The response time of the ionized absorbers allows us to constrain their electron density and location. We find that one component (with intermediate ionization) must be located within the obscuring torus at a distance 2.7 × 10{sup 17} cm from the central engine. This outflowing component likely originated in the accretion disk. The three remaining components are at distances larger than 10{sup 16}-10{sup 17} cm. Two of the absorbing components in the soft X-rays have similar outflow velocities and locations. These components may be in pressure equilibrium, forming a multi-phase medium, if the gas has metallicity larger than the solar one (≳ 5 Z {sub ☉}). We also search for variations in the covering factor of the ionized absorbers (although partial

  20. Application of High-Resolution Thermal Infrared Remote Sensing and GIS to Assess the Urban Heat Island Effect

    NASA Technical Reports Server (NTRS)

    Lo, C. P.; Quattrochi, D. A.; Luvall, J. C.

    1997-01-01

    Day and night airborne thermal infrared image data at 5 m spatial resolution acquired with the 15-channel (0.45 micron - 12.2 micron) Advanced Thermal and Land Applications Sensor (ATLAS) over Alabama, Huntsville on 7 September, 1994 were used to study changes in the thermal signatures of urban land cover types between day and night. Thermal channel number 13 (9.6 micron - 10.2 micron) data with the best noise-equivalent temperature change (NEAT) of 0.25 C after atmospheric corrections and temperature calibration were selected for use in this analysis. This research also examined the relation between land cover irradiance and vegetation amount, using the Normalized Difference Vegetation Index (NDVI), obtained by ratioing the difference and the sum of the red (channel number 3: 0.60-0.63 micron) and reflected infrared (channel number 6: 0.76-0.90 micron) ATLAS data. Based on the mean radiance values, standard deviations, and NDVI extracted from 351 pairs of polygons of day and night channel number 13 images for the city of Huntsville, a spatial model of warming and cooling characteristics of commercial, residential, agricultural, vegetation, and water features was developed using a GIS approach. There is a strong negative correlation between NDVI and irradiance of residential, agricultural, and vacant/transitional land cover types, indicating that the irradiance of a land cover type is greatly influenced by the amount of vegetation present. The predominance of forests, agricultural, and residential uses associated with varying degrees of tree cover showed great contrasts with commercial and services land cover types in the center of the city, and favors the development of urban heat islands. The high-resolution thermal infrared images match the complexity of the urban environment, and are capable of characterizing accurately the urban land cover types for the spatial modeling of the urban heat island effect using a GIS approach.

  1. Far-infrared spectra of acetanilide revisited

    NASA Astrophysics Data System (ADS)

    Spire, A.; Barthes, M.; Kellouai, H.; De Nunzio, G.

    2000-03-01

    A new investigation of the temperature dependence of the far-infrared spectra of acetanilide and some isotopomers is presented. Four absorption bands are considered at 31, 42, 64, and 80 cm-1, and no significant change of their integrated intensity is observed when reducing the temperature. The temperature induced frequency shift values and other properties of these bands are consistent with an assignment as anharmonic lattice phonons. These results rule out the assignment of the 64, 80, and 106 cm-1 bands as normal modes of the polaronic excitation, as previously suggested.

  2. A Thermal Infrared Emission Spectra Library for Unpowdered Meteorites

    NASA Astrophysics Data System (ADS)

    Ashley, J. W.; Christensen, P. R.

    2007-12-01

    interpretation of asteroid spectroscopic studies in the mid-infrared [4]. However, the high-resolution Itokawa imaging results of the Hayabusa mission have shown that not all asteroid surfaces are dominated by powdered materials [e.g. 5]. It is therefore anticipated that whole-rock, mid-infrared emission spectra may serve a further purpose in studies conducted with Spitzer Space Telescope and other space-born observatories equipped with mid-infrared detectors. The library will therefore continue to be augmented with additional spectra, to include unweathered carbonaceous chondrites and achondrites at a minimum. All spectra are available through the Arizona State University Thermal Emission Spectral Library. References: [1] Sato K. and Miyamoto M. (1998) Antarctic Meteorite Research 11, 155-162. [2] Salisbury J.W. et al. (1991) NASA Technical Memorandum #4300, 262-204. [3] Dameron S.N. and Burbine T.H. (2006) LPSC XXXVII, abstract #1828. [4] Emery J.P. et al. (2006) Icarus 182, 496-512. [5] Miyamoto et al. (2007) Science 316, 1011- 1014.

  3. High-Resolution 4.7 Micron Keck/NIRSPEC Spectra of Protostars. II. Detection of the 13CO Isotope in Icy Grain Mantles

    NASA Astrophysics Data System (ADS)

    Boogert, A. C. A.; Blake, G. A.; Tielens, A. G. G. M.

    2002-09-01

    The high-resolution (R=25,000) infrared M-band spectrum of the massive protostar NGC 7538 IRS 9 shows a narrow absorption feature at 4.779 μm (2092.3 cm-1) that we attribute to the vibrational stretching mode of the 13CO isotope in pure CO icy grain mantles. This is the first detection of 13CO in icy grain mantles in the interstellar medium. The 13CO band is a factor of 2.3 narrower than the apolar component of the 12CO band. With this in mind, we discuss the mechanisms that broaden solid-state absorption bands. It is shown that ellipsoidally shaped pure CO grains fit the bands of both isotopes at the same time. Slightly worse but still reasonable fits are also obtained by CO embedded in N2-rich ices and thermally processed O2-rich ices. In addition, we report new insights into the nature and evolution of interstellar CO ices by comparing the very high resolution multicomponent solid 12CO spectrum of NGC 7538 IRS 9 with that of the previously studied low-mass source L1489 IRS. The narrow absorption of apolar CO ices is present in both spectra but much stronger in NGC 7538 IRS 9. It is superposed on a smooth broad absorption feature well fitted by a combination of CO2 and H2O-rich laboratory CO ices. The abundances of the latter two ices, scaled to the total H2O ice column, are the same in both sources. We thus suggest that thermal processing manifests itself as evaporation of apolar ices only and not the formation of CO2 or polar ices. Finally, the decomposition of the 12CO band is used to derive the 12CO/13CO abundance ratio in apolar ices. A ratio of 12CO/13CO=71+/-15 (3 σ) is deduced, in good agreement with gas-phase CO studies (~77) and the solid 12CO2/13CO2 ratio of 80+/-11 found in the same line of sight. The implications for the chemical path along which CO2 is formed are discussed. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the

  4. Re-analysis of the (100), (001), and (020) rotational structure of SO2 on the basis of high resolution FTIR spectra

    NASA Astrophysics Data System (ADS)

    Ulenikov, O. N.; Onopenko, G. A.; Gromova, O. V.; Bekhtereva, E. S.; Horneman, V.-M.

    2013-11-01

    Three infrared spectra, weak (W), medium (M), and strong (S), of the 32SO2 molecule were recorded with high resolution in the 1000-1500 cm-1 region. Spectra were recorded with the Fourier Transform interferometer Bruker IFS-120 HR in Oulu (Finland) with different pressures, absorption path lengths, and recording time. That allowed us to record not only the ν1 and ν3 bands with higher values of quantum numbers J and Ka than it was made earlier, but to record for the first time very weak 2ν2 band. In this case, transitions with the values J/Kamax. equal to 89/37, 109/28, and 54/9 were assigned in the experimental spectra for the bands ν1, ν3, and 2ν2, respectively. As it became clear in the course of the analysis, the rotational parameters of the ground vibrational state, known in the literature, do not describe suitably the ground state combination differences (GSCD) for the states with the value Ka>26-27. As a consequence, the ground state rotational parameters were improved on the basis of our experimental data. The 12 131 transitions assigned in the experimental spectrum (7618, 3952, and 561 transitions of the bands ν1, ν3, and 2ν2, respectively) were used for determination of ro-vibrational energy values of the vibrational states (100), (001), and (020). The lasts were used then in the fit procedure together with known in the literature high accurate sub-millimeter wave data. Resonance interactions between all three vibrational states have been taken into account in the Hamiltonian used for the fit. As a result, the 51 varied parameters, obtained from the fit, reproduce 4063 ro-vibrational energies of the states (100), (001), and (020) (12 131 initial experimental transitions) with accuracies close to experimental uncertainties: the rms deviation is 6.1×10-5 cm-1, 9.7×10-5 cm-1, and 13.9×10-5 cm-1 for our FTIR data (for the (100), (001), and (020) states, respectively), and comparable with experimental uncertainties for heterodyne data.

  5. High-Resolution Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Dozier, Jeff; Goetz, Alexander F. H.

    1990-01-01

    Earth resources observed in greater detail. High-Resolution Imaging Spectrometer, undergoing development for use in NASA's Earth Observing System, measures reflectance of Earth's surface in visible and near-infrared wavelengths. From an orbit around Earth, instrument scans surface of Earth in 200 wavelength bands simultaneously. Produces images enabling identification of minerals in rocks and soils, important algal pigments in oceans and inland waters, changes in spectra associated with biochemistry of plant canopies, compositions of atmospheric aerosols, sizes of grains in snow, and contamination of snow by impurities that absorb visible light.

  6. A high-resolution three-dimensional far-infrared thermal and true-color imaging system for medical applications.

    PubMed

    Cheng, Victor S; Bai, Jinfen; Chen, Yazhu

    2009-11-01

    As the needs for various kinds of body surface information are wide-ranging, we developed an imaging-sensor integrated system that can synchronously acquire high-resolution three-dimensional (3D) far-infrared (FIR) thermal and true-color images of the body surface. The proposed system integrates one FIR camera and one color camera with a 3D structured light binocular profilometer. To eliminate the emotion disturbance of the inspector caused by the intensive light projection directly into the eye from the LCD projector, we have developed a gray encoding strategy based on the optimum fringe projection layout. A self-heated checkerboard has been employed to perform the calibration of different types of cameras. Then, we have calibrated the structured light emitted by the LCD projector, which is based on the stereo-vision idea and the least-squares quadric surface-fitting algorithm. Afterwards, the precise 3D surface can fuse with undistorted thermal and color images. To enhance medical applications, the region-of-interest (ROI) in the temperature or color image representing the surface area of clinical interest can be located in the corresponding position in the other images through coordinate system transformation. System evaluation demonstrated a mapping error between FIR and visual images of three pixels or less. Experiments show that this work is significantly useful in certain disease diagnoses. PMID:19782632

  7. The Apache Point Observatory Galactic Evolution Experiment (APOGEE) high-resolution near-infrared multi-object fiber spectrograph

    NASA Astrophysics Data System (ADS)

    Wilson, John C.; Hearty, Fred; Skrutskie, Michael F.; Majewski, Steven; Schiavon, Ricardo; Eisenstein, Daniel; Gunn, Jim; Blank, Basil; Henderson, Chuck; Smee, Stephen; Barkhouser, Robert; Harding, Al; Fitzgerald, Greg; Stolberg, Todd; Arns, Jim; Nelson, Matt; Brunner, Sophia; Burton, Adam; Walker, Eric; Lam, Charles; Maseman, Paul; Barr, Jim; Leger, French; Carey, Larry; MacDonald, Nick; Horne, Todd; Young, Erick; Rieke, George; Rieke, Marcia; O'Brien, Tom; Hope, Steve; Krakula, John; Crane, Jeff; Zhao, Bo; Carr, Mike; Harrison, Craig; Stoll, Robert; Vernieri, Mary A.; Holtzman, Jon; Shetrone, Matt; Allende-Prieto, Carlos; Johnson, Jennifer; Frinchaboy, Peter; Zasowski, Gail; Bizyaev, Dmitry; Gillespie, Bruce; Weinberg, David

    2010-07-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) will use a dedicated 300-fiber, narrow-band (1.5-1.7 micron), high resolution (R~30,000), near-infrared spectrograph to survey approximately 100,000 giant stars across the Milky Way. This survey, conducted as part of the Sloan Digital Sky Survey III (SDSS III), will revolutionize our understanding of kinematical and chemical enrichment histories of all Galactic stellar populations. The instrument, currently in fabrication, will be housed in a separate building adjacent to the 2.5 m SDSS telescope and fed light via approximately 45-meter fiber runs from the telescope. The instrument design includes numerous technological challenges and innovations including a gang connector that allows simultaneous connection of all fibers with a single plug to a telescope cartridge that positions the fibers on the sky, numerous places in the fiber train in which focal ratio degradation must be minimized, a large (290 mm x 475 mm elliptically-shaped recorded area) mosaic-VPH, an f/1.4 sixelement refractive camera featuring silicon and fused silica elements with diameters as large as 393 mm, three near-within a custom, LN2-cooled, stainless steel vacuum cryostat with dimensions 1.4 m x 2.3 m x 1.3 m.

  8. Calibration of the Visible and Near-Infrared Channels of the Advanced Very High Resolution Radiometer (AVHRR) After Launch

    NASA Technical Reports Server (NTRS)

    Rao, C. R. Nagaraja; Chen, Jianhua

    1993-01-01

    The relative degradation in time of the visible(channel 1: approx.0.58-0.6 microns) and near-infrared(channel 2: approx. O.72-1.1 microns) channels of the Advanced Very High Resolution Radiometer(AVHRR), onboard the NOAA Polar-orbiting Operational Environmental Satellites(POES), has been determined, using the southeastern Libyan desert(21-23 deg N latitude; 28- 29 deg E longitude) as a time-invariant calibration target. A statistical procedure was used on the reflectance data for the two channels from the B3 data of the International Satellite Cloud Climatology Project(ISCCP) to obtain the degradation rates for the AVERRs on NOAA-7, -9, and -11 spacecraft. The degradation rates per year for channels 1 and 2 are respectively: 3.6% and 4.3%(NOAA-7); 5.9% and 3.5%(NOAA-9); and 1.2% and 2.0%(NOAA-11). The use of the degradation rates thus determined, in conjunction with 'absolute' calibrations obtained from congruent aircraft and satellite measurements, in the development of correction algorithms is illustrated with the AVHRR on the NOAA-9 spacecraft.

  9. Using radiative transfer models to study the atmospheric water vapor content and to eliminate telluric lines from high-resolution optical spectra

    NASA Astrophysics Data System (ADS)

    Gardini, A.; Maíz Apellániz, J.; Pérez, E.; Quesada, J. A.; Funke, B.

    2013-05-01

    The Radiative Transfer Model (RTM) and the retrieval algorithm, incorporated in the SCIATRAN 2.2 software package developed at the Institute of Remote Sensing/Institute of Enviromental Physics of Bremen University (Germany), allows to simulate, among other things, radiance/irradiance spectra in the 2400--24 000 Å range. In this work we present applications of RTM to two case studies. In the first case the RTM was used to simulate direct solar irradiance spectra, with different water vapor amounts, for the study of the water vapor content in the atmosphere above Sierra Nevada Observatory. Simulated spectra were compared with those measured with a spectrometer operating in the 8000--10 000 Å range. In the second case the RTM was used to generate telluric model spectra to subtract the atmospheric contribution and correct high-resolution stellar spectra from atmospheric water vapor and oxygen lines. The results of both studies are discussed.

  10. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene.

    PubMed

    Mackie, Cameron J; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Buma, Wybren Jan; Lee, Timothy J; Tielens, Alexander G G M

    2015-12-14

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C-H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned. PMID:26671382

  11. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene

    SciTech Connect

    Mackie, Cameron J. Candian, Alessandra; Tielens, Alexander G. G. M.; Huang, Xinchuan; Maltseva, Elena; Buma, Wybren Jan; Petrignani, Annemieke; Oomens, Jos; Lee, Timothy J.

    2015-12-14

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C–H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned.

  12. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene

    NASA Astrophysics Data System (ADS)

    Mackie, Cameron J.; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Buma, Wybren Jan; Lee, Timothy J.; Tielens, Alexander G. G. M.

    2015-12-01

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C-H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned.

  13. Atlas of high resolution infrared spectra of carbon dioxide, February 1983

    NASA Technical Reports Server (NTRS)

    Benner, D. C.; Rinslad, C. P.; Richardson, D. J.; Soo, T. H.; Smith, M. A. H.

    1983-01-01

    A long path, low pressure laboratory spectrum of carbon dioxide is presented for the spectral region 1830 to 2010/cm. The data were recorded at 0.01/cm resolution and room temperature with the Fourier transform spectrometer in the McMath solar telescope complex at Kitt Peak National Observatory. A list of positions and assignments is given for the 1038 lines observed in this region. A total of 30 bands and subbands of 12C16O2, 13C16O2, 12C16O18O, 12C16O17O, and 13C16O18O were observed.

  14. High resolution infrared studies of dynamics in low temperature matrics: Vibrational dephasing for SeF/sub 6/ in noble gas solids

    SciTech Connect

    Jones, L.H.; Swanson, B.I.

    1981-03-15

    High resolution infrared absorption spectra for the upsilon/sub 3/ mode of SeF/sub 6/ in low temperature noble gas matrices have been observed. A remarkable amount of structure is observed leading to the conclusion that multiple trapping sites as well as site symmetry splittings, similar to those observed previously for SF/sub 6/, are common. Temperature dependent studies give a rich display of dynamics arising from host--guest interactions. These give evidence for dynamic exchange among equivalent low symmetry sites within a given trapping cage. This exchange is evidence for a dephasing of the components of upsilon/sub 3/ by a local site phonon mode in resonance with part of the phonon bath. Unexpected matrix shifts and intensity changes with temperature have been observed. Accurate isotope shifts, especially in a neon matrix, are shown to be useful for calculation of potential constants. A discussion of host--guest interactions, dephasing, and dynamic site exchange in these matrices is given.

  15. MID-INFRARED PROPERTIES OF OH MEGAMASER HOST GALAXIES. I. SPITZER IRS LOW- AND HIGH-RESOLUTION SPECTROSCOPY

    SciTech Connect

    Willett, Kyle W.; Darling, Jeremy; Spoon, Henrik W. W.; Charmandaris, Vassilis; Armus, Lee

    2011-03-15

    We present mid-infrared spectra and photometry from the Infrared Spectrograph on the Spitzer Space Telescope for 51 OH megamasers (OHMs), along with 15 galaxies confirmed to have no megamaser emission above L {sub OH} = 10{sup 2.3} L {sub sun}. The majority of galaxies display moderate-to-deep 9.7 {mu}m amorphous silicate absorption, with OHM galaxies showing stronger average absorption and steeper 20-30 {mu}m continuum emission than non-masing galaxies. Emission from multiple polycyclic aromatic hydrocarbons (PAHs), especially at 6.2, 7.7, and 11.3 {mu}m, is detected in almost all systems. Fine-structure atomic emission (including [Ne II], [Ne III], [S III], and [S IV]) and multiple H{sub 2} rotational transitions are observed in more than 90% of the sample. A subset of galaxies show emission from rarer atomic lines, such as [Ne V], [O IV], and [Fe II]. Fifty percent of the OHMs show absorption from water ice and hydrogenated amorphous carbon grains, while absorption features from CO{sub 2}, HCN, C{sub 2}H{sub 2}, and crystalline silicates are also seen in several OHMs. Column densities of OH derived from 34.6 {mu}m OH absorption are similar to those derived from 1667 MHz OH absorption in non-masing galaxies, indicating that the abundance of masing molecules is similar for both samples. This data paper presents full mid-infrared spectra for each galaxy, along with measurements of line fluxes and equivalent widths, absorption feature depths, and spectral indices.

  16. First Infrared Spectra of Nitrous Oxide Pentamer

    NASA Astrophysics Data System (ADS)

    Rezaei, M.; Oliaee, J. Norooz; Moazzen-Ahmadi, N.; McKellar, A. R. W.

    2012-06-01

    High resolution spectra have previously been studied for N_2O dimers (two isomers), trimers (one isomer), and tetramers (two isomers). Here, we assign two new bands to the N_2O pentamer. The bands are observed in the region of the N_2O νb{1} fundamental using a tunable laser to probe a pulsed supersonic slit jet expansion. They are centered at 2233.9 and 2236.4 wn for 14N_2O, and at 2164.4 and 2166.8 wn for 15N_2O. Attribution to the pentamer is based on comparison of the observed rotational constants with theoretical ones from calculated cluster structures based on two rather different N_2O pair potentials. The first potential function is from a recent high level ab initio study. The second potential is a relatively simple empirical one, based partly on fitting to bulk properties. The likely pentamer structure is a completely unsymmetric one. It can be visualized starting with a highly symmetric oblate tetramer which is attacked by a fifth monomer, locating itself at a favorable distance and breaking the symmetry. Interestingly, analysis of the two bands yields very similar but not quite identical ground state parameters. We believe that they are due to distinct isomers having this same basic structure but differing in the orientation direction of one N_2O monomer. [1] R. Dawes, X.-G. Wang, A.W. Jasper, and T. Carrington, Jr., {J. Chem. Phys.} {133}, 134304 (2010). [2] B. Kutcha, R.D. Etters, and R. LeSar, {J. Chem. Phys.} {97}, 5662 (1992). [3] J.N. Oliaee, M. Dehghany, N. Moazzen-Ahmadi, and A.R.W. McKellar, {J. Chem. Phys.} {134}, 074310 (2011).

  17. Polarized Matrix Infrared Spectra of Cyclopentadienone

    NASA Astrophysics Data System (ADS)

    Ormond, Thomas K.; Scheer, Adam M.; Ellison, G. Barney; Nimlos, Mark R.; Daily, John W.; Stanton, John F.

    2012-06-01

    We are developing a resistively-heated SiC μtubular reactor with a 100 μsec residence time to study the thermal cracking of biomass monomers. The decomposition products are identified by two independent techniques: 118.2 nm VUV photoionization mass spectrometry (PIMS) and matrix infrared spectroscopy. Many lignins thermally crack to produce cyclopentadienone (m/z 80) and its derivatives. Subsequent decomposition of these cyclopentadienones results in formation of substituted acetylenes which are known precursors to polycyclic aromatic hydrocarbons and soot. Due to its anitaromatic character, cyclopentadienone is highly reactive and presents an interesting spectroscopic system. Pyrolysis of {o}-phenylene sulfite (m/z 156) is a convenient precursor for cyclopentadienone. In this work we report the polarized matrix infrared absorption spectra of cyclopentadienone and d_4-cyclopentadienone. The PIMS results corroborate the thermal decomposition steps of phenylene sulfite. {Ab initio} coupled-cluster anharmonic force field calculations are used to guide the vibrational assignments. A. M. Scheer, C. Murkarakate, D. J. Robichaud, M. R. Nimlos, and G. B. Ellison J. Phys. Chem. A 115, 13381 (2011)

  18. Classification of infrared spectra from skin tumors

    NASA Astrophysics Data System (ADS)

    McIntosh, Laura M.; Mansfield, James R.; Crowson, A. Neil; Toole, John W. P.; Mantsch, Henry H.; Jackson, Michael

    2000-05-01

    The clinical differential diagnosis of skin tumors is an often-challenging task, to which the probing of skin with mid- and near-infrared (IR) light may be contributory. The development of objective methods for the analysis of IR spectra remains a major hurdle to developing clinically useful applications. The authors highlight different processing methods for IR spectra from skin biopsies and in-vivo skin tumors. Spectroscopic maps of biopsies of basal cell, squamous cell and melanocytic neoplasms were objectively grouped into distinct clusters that corresponded with tumor, epidermis, dermis, follicle and fat. Normal and abnormal skin components were located within maps using a search engine based upon linear discriminant analysis (LDA). In all instances, areas of tumor were distinct from normal tissue in biopsies. In-vivo, near-IR spectroscopy and LDA allowed discrimination between benign and malignant skin lesions with a high degree of accuracy. We conclude that IR spectroscopy has significant diagnostic promise in the skin cancer arena. The analytical methods described can now be used to create a powerful classification scheme in which to detect skin tumor cells within biopsied and living skin.

  19. Optimized approach to retrieve information on the tropospheric and stratospheric carbonyl sulfide (OCS) vertical distributions above Jungfraujoch from high-resolution FTIR solar spectra.

    NASA Astrophysics Data System (ADS)

    Lejeune, Bernard; Mahieu, Emmanuel; Servais, Christian; Duchatelet, Pierre; Demoulin, Philippe

    2010-05-01

    Carbonyl sulfide (OCS), which is produced in the troposphere from both biogenic and anthropogenic sources, is the most abundant gaseous sulfur species in the unpolluted atmosphere. Due to its low chemical reactivity and water solubility, a significant fraction of OCS is able to reach the stratosphere where it is converted to SO2 and ultimately to H2SO4 aerosols (Junge layer). These aerosols have the potential to amplify stratospheric ozone destruction on a global scale and may influence Earth's radiation budget and climate through increasing solar scattering. The transport of OCS from troposphere to stratosphere is thought to be the primary mechanism by which the Junge layer is sustained during nonvolcanic periods. Because of this, long-term trends in atmospheric OCS concentration, not only in the troposphere but also in the stratosphere, are of great interest. A new approach has been developed and optimized to retrieve atmospheric abundance of OCS from high-resolution ground-based infrared solar spectra by using the SFIT-2 (v3.91) algorithm, including a new model for solar lines simulation (solar lines often produce significant interferences in the OCS microwindows). The strongest lines of the ν3 fundamental band of OCS at 2062 cm-1 have been systematically evaluated with objective criteria to select a new set of microwindows, assuming the HITRAN 2004 spectroscopic parameters with an increase in the OCS line intensities of the ν3band main isotopologue 16O12C32S by 15.79% as compared to HITRAN 2000 (Rothman et al., 2008, and references therein). Two regularization schemes have further been compared (deducted from ATMOS and ACE-FTS measurements or based on a Tikhonov approach), in order to select the one which optimizes the information content while minimizing the error budget. The selected approach has allowed us to determine updated OCS long-term trend from 1988 to 2009 in both the troposphere and the stratosphere, using spectra recorded on a regular basis with

  20. Ab initio infrared and Raman spectra

    NASA Astrophysics Data System (ADS)

    Fredkin, Donald R.; Komornicki, Andrew; White, Steven R.; Wilson, Kent R.

    1983-06-01

    We discuss several ways in which molecular absorption and scattering spectra can be computed ab initio, from the fundamental constants of nature. These methods can be divided into two general categories. In the first, or sequential, type of approach, one first solves the electronic part of the Schrödinger equation in the Born-Oppenheimer approximation, mapping out the potential energy, dipole moment vector (for infrared absorption) and polarizability tensor (for Raman scattering) as functions of nuclear coordinates. Having completed the electronic part of the calculation, one then solves the nuclear part of the problem either classically or quantum mechanically. As an example of the sequential ab initio approach, the infrared and Raman rotational and vibrational-rotational spectral band contours for the water molecule are computed in the simplest rigid rotor, normal mode approximation. Quantum techniques are used to calculate the necessary potential energy, dipole moment, and polarizability information at the equilibrium geometry. A new quick, accurate, and easy to program classical technique involving no reference to Euler angles or special functions is developed to compute the infrared and Raman band contours for any rigid rotor, including asymmetric tops. A second, or simultaneous, type of ab initio approach is suggested for large systems, particularly those for which normal mode analysis is inappropriate, such as liquids, clusters, or floppy molecules. Then the curse of dimensionality prevents mapping out in advance the complete potential, dipole moment, and polarizability functions over the whole space of nuclear positions of all atoms, and a solution in which the electronic and nuclear parts of the Born-Oppenheimer approximation are simultaneously solved is needed. A quantum force classical trajectory (QFCT) molecular dynamic method, based on linear response theory, is described, in which the forces, dipole moment, and polarizability are computed quantum

  1. High Resolution Infrared Spectroscopy of CH_3F-({ortho}-H_2){n} Cluster in Solid {para}-H_2

    NASA Astrophysics Data System (ADS)

    Kawasaki, Hiroyuki; Mizoguchi, Asao; Kanamori, Hideto

    2015-06-01

    The absorption spectrum of the ν3 (C-F stretching) mode of CH_3F in solid {para}-H_2 by FTIR showed a series of equal interval peaks. Their interpretation was that the {}-th peak of this series was due to CH_3F-({ortho}-H_2){n} clusters which were formed CH_3F and {n}'s {ortho}-H_2 in first nearest neighbor sites of the {para}-H_2 crystal with {hcp} structure. In order to understand this system in more detail, we have studied these peaks, especially {n} = 0 - 3 corresponding to 1037 - 1041 wn, by using high-resolution and high-sensitive infrared quantum cascade (QC) laser spectroscopy. Before now, we found many peaks around each {n}-th peak of the cluster, which we didn't know their origins. We observed photochromic phenomenon of these peaks by taking an advantage of the high brightness of the laser. In this study, we focus on satellite series consisting of six peaks which locate at the lower energy side of each main peak. All the peaks showed a common red shouldered line profile, which corresponds to partly resolved transitions of {ortho}- and {para}- CH_3F. The spectral pattern and time behavior of the peaks may suggest that these satellite series originate from a family of CH_3F clusters involving {ortho}-H_2 in second nearest neighbor sites. A model function assuming this idea is used to resolve the observed spectrum into each Lorentzian component, and then some common features of the satellite peaks are extracted and the physical meanings of them will be discussed. K. Yoshioka and D. T. Anderson, J. Chem. Phys. 119 (2003) 4731-4742 A. R. W. McKellar, A. Mizoguchi, and H. Kanamori, J. Chem. Phys. 135 (2011) 124511 A. R. W. McKellar, A. Mizoguchi, and H. Kanamori, Phys. Chem. Chem. Phys. 13 (2011) 11587-11589.

  2. High resolution interferometry of cool stars

    NASA Technical Reports Server (NTRS)

    Lambert, D. L.

    1974-01-01

    A description is given of results obtained in a program of infrared high resolution spectroscopy of cool stars. The nature of infrared stellar spectra is considered along with questions regarding astrophysics and stellar infrared spectroscopy. An abundance analysis for alpha Ori (Betelgeuse) is conducted. The C-12/C-13 abundance ratio is examined and attention is given to the O-16/O-18 and O-16/O-17 abundance ratios. M stars and SiO vibration-rotation bands are discussed and questions regarding the characteristics of the molecular hydrogen quadrupole vibration-rotation lines are explored.

  3. High resolution X-ray spectra of solar flares. V - Interpretation of inner-shell transitions in Fe XX-Fe XXIII

    NASA Technical Reports Server (NTRS)

    Doschek, G. A.; Feldman, U.; Cowan, R. D.

    1981-01-01

    The paper examines high-resolution solar flare iron line spectra recorded between 1.82 and 1.97 A by a spectrometer flown by the Naval Research Laboratory on an Air Force spacecraft launched on 1979 February 24. The emission line spectrum is due to inner-shell transitions in the ions Fe XX-Fe XXV. Using theoretical spectra and calculations of line intensities obtained by methods discussed by Merts, Cowan, and Magee (1976), electron temperatures as a function of time for two large class X flares are derived. These temperatures are deduced from intensities of lines of Fe XXII, Fe XXIII, and Fe XXIV. The determination of the differential emission measure between about 12-million and 20-million K using these temperatures is considered. The possibility of determining electron densities in flare and tokamak plasmas using the inner-shell spectra of Fe XXI and Fe XX is discussed.

  4. Characterization of REE-Bearing Minerals and Synthetic Materials Using High Resolution Ultraviolet to Near-Infrared Reflectance Spectroscopy

    NASA Astrophysics Data System (ADS)

    Hoefen, T. M.; Livo, K. E.; Giles, S. A.; Lowers, H. A.; Swayze, G. A.; Taylor, C. D.; Verplanck, P. L.; Emsbo, P.; Koenig, A.; Mccafferty, A. E.

    2014-12-01

    Diagnostic crystal field 4fn-4fn transition features in the ultraviolet (UV) to near-infrared (NIR) region of the electromagnetic spectrum have been observed in many common rare earth element (REE)-bearing minerals. The partial filling of the 4f electron shell combined with a shielding effect caused by the fully filled 5s25p6-electron shells, which weaken any effects from external magnetic or electric fields on the electrons, makes rare earth ions unique. The narrow absorption features occur as a result of parity forbidden transitions and crystal field splitting of the trivalent REEs, and since they are well shielded, only subtle wavelengths shifts are seen in their spectral features. Synthetic single REE phosphates, carbonates, oxides, hydroxides and glasses have been measured in the lab to help identify absorption band positions that are characteristic of each REE as they occur in different minerals. Because spectral resolution is critical to identifying shifts in the absorption band positions, these materials have been measured on several different high resolution spectrometers. Using a combination of Ocean Optics USB 2000+ UV-VIS, USB2000+ VIS-NIR and ASD FS 4 spectrometers we have characterized REE-bearing materials from 0.2 to 2.5 microns with a spectral resolution of ~2 nm between 0.2 and 1.0 microns and 11 to 12 nm between 1.0 and 2.5 microns. Results to date suggest that wavelength shifts and variations in the degree of crystal field splitting allow spectral differentiation between REE-bearing minerals. To support these results, a comprehensive suite of marine phosphates, paleo-beach placers, IOCG deposits, alkaline to peralkaline igneous complexes, pegmatites associated with alkaline magmas and carbonatite intrusives, have been measured and included in our database. Core, rock chips, billets, sediment samples and grab samples were manually scanned to identify the most intense or spectrally different REE features. While REE-bearing minerals have been

  5. Infrared spectra of lunar soil analogs. [spectral reflectance of minerals

    NASA Technical Reports Server (NTRS)

    Aronson, J. R.

    1977-01-01

    The infrared spectra of analogs of lunar soils were investigated to further the development of methodology for interpretation of remotely measured infrared spectra of the lunar surface. The optical constants of dunite, bytownite, augite, ilmenite, and a mare glass analog were obtained. The infrared emittance spectra of powdered minerals were measured and compared with spectra calculated by the reflectance theory using a catalog of optical constants. The results indicate that the predictions of the theory closely simulate the experimental measurements if the optical constants are properly derived.

  6. High resolution observed in 800 MHz DNP spectra of extremely rigid type III secretion needles.

    PubMed

    Fricke, Pascal; Mance, Deni; Chevelkov, Veniamin; Giller, Karin; Becker, Stefan; Baldus, Marc; Lange, Adam

    2016-08-01

    The cryogenic temperatures at which dynamic nuclear polarization (DNP) solid-state NMR experiments need to be carried out cause line-broadening, an effect that is especially detrimental for crowded protein spectra. By increasing the magnetic field strength from 600 to 800 MHz, the resolution of DNP spectra of type III secretion needles (T3SS) could be improved by 22 %, indicating that inhomogeneous broadening is not the dominant effect that limits the resolution of T3SS needles under DNP conditions. The outstanding spectral resolution of this system under DNP conditions can be attributed to its low overall flexibility. PMID:27351550

  7. A Simple Approach for Obtaining High Resolution, High Sensitivity ¹H NMR Metabolite Spectra of Biofluids with Limited Mass Supply

    SciTech Connect

    Hu, Jian Zhi; Rommereim, Donald N.; Wind, Robert A.; Minard, Kevin R.; Sears, Jesse A.

    2006-11-01

    A simple approach is reported that yields high resolution, high sensitivity ¹H NMR spectra of biofluids with limited mass supply. This is achieved by spinning a capillary sample tube containing a biofluid at the magic angle at a frequency of about 80Hz. A 2D pulse sequence called ¹H PASS is then used to produce a high-resolution ¹H NMR spectrum that is free from magnetic susceptibility induced line broadening. With this new approach a high resolution ¹H NMR spectrum of biofluids with a volume less than 1.0 µl can be easily achieved at a magnetic field strength as low as 7.05T. Furthermore, the methodology facilitates easy sample handling, i.e., the samples can be directly collected into inexpensive and disposable capillary tubes at the site of collection and subsequently used for NMR measurements. In addition, slow magic angle spinning improves magnetic field shimming and is especially suitable for high throughput investigations. In this paper first results are shown obtained in a magnetic field of 7.05T on urine samples collected from mice using a modified commercial NMR probe.

  8. High-Resolution Infrared Spectroscopy Slit-Jet Cooled Hydroxymethyl Radical (CH_2OH): CH Symmetric Stretching Mode

    NASA Astrophysics Data System (ADS)

    Wang, Fang; Chang, Chih-Hsuan; Nesbitt, David

    2014-06-01

    Hydroxymethyl radical (CH_2OH) plays an important role in combustion and environmental chemistry as a reactive intermediate. Reisler's group published the first rotationally resolved spectroscopy of CH_2OH with determined band origins for fundamental CH symmetric stretch state, CH asymmetric stretch state and OH stretch state, respectively. Here CH_2OH was first studied via sub-Doppler infrared spectroscopy in a slit-jet supersonic discharge expansion source. Rotationally resolved direct absorption spectra in the CH symmetric stretching mode were recorded. As a result of the low rotational temperature and sub-Doppler linewidths, the tunneling splittings due to the large amplitude of COH torsion slightly complicate the spectra. Each of the ground vibration state and the CH symmetric stretch state includes two levels. One level, with a 3:1 nuclear spin statistic ratio for Ka=0+/Ka=1+, is labeled as ``+". The other tunneling level, labeled as ``-", has Ka=0-/Ka=1- states with 1:3 nuclear spin statistics. Except for the Ka=0+ ← 0+ band published before, more bands (Ka=1+ ← 1+, Ka=0- ← 0- and Ka=1- ← 1-) were identified. The assigned transitions were fit to a Watson A-reduced symmetric top Hamiltonian to improve the accuracy of the band origin of CH symmetric state. The rotational parameters for both ground and CH symmetric stretch state were well determined. L. Feng, J. Wei and H. Reisler, J. Phys. Chem. A, Vol. 108. M. A. Roberts, E. N. Sharp-Williams and D. J. Nesbitt, J. Phys. Chem. A 2013, 117, 7042-7049

  9. Kea: A New Tool to Obtain Stellar Parameters from Low to Moderate Signal-to-noise and High-resolution Echelle Spectra

    NASA Astrophysics Data System (ADS)

    Endl, Michael; Cochran, William D.

    2016-09-01

    In this paper, we describe Kea a new spectroscopic fitting method to derive stellar parameters from moderate to low signal-to-noise, high-resolution spectra. We developed this new tool to analyze the massive data set of the Kepler mission reconnaissance spectra that we have obtained at McDonald Observatory. We use Kea to determine effective temperatures (T eff), metallicity ([Fe/H]), surface gravity (log g), and projected rotational velocity (v{sin}i). Kea compares the observations to a large library of synthetic spectra that covers a wide range of different T eff, [Fe/H], and log g values. We calibrated Kea on observations of well-characterized standard stars (the Kepler field “platinum” sample) that range in T eff from 5000 to 6500 K, in [Fe/H] from ‑0.5 to +0.4 dex, and in log g from 3.2 to 4.6 dex. We then compared the Kea results from reconnaissance spectra of 45 Kepler objects of interest (KOIs) to stellar parameters derived from higher signal-to-noise spectra obtained with Keck/HIRES. We find typical uncertainties of 100 K in T eff, 0.12 dex in [Fe/H], and 0.18 dex in log g. Named after Nestor notabilis an alpine parrot native to New Zealand.

  10. First retrievals of HCFC-142b from ground-based high-resolution FTIR solar observations: application to high-altitude Jungfraujoch spectra

    NASA Astrophysics Data System (ADS)

    Mahieu, Emmanuel; O'Doherty, Simon; Reimann, Stefan; Vollmer, Martin; Bader, Whitney; Bovy, Benoît; Lejeune, Bernard; Demoulin, Philippe; Roland, Ginette; Servais, Christian; Zander, Rodolphe

    2013-04-01

    Hydrofluorocarbons (HCFCs) are the first substitutes to the long-lived ozone depleting halocarbons, in particular the chlorofluorocarbons (CFCs). Given the complete ban of the CFCs by the Montreal Protocol, its Amendments and Adjustments, HCFCs are on the rise, with current rates of increase substantially larger than at the beginning of the 21st century. HCFC-142b (CH3CClF2) is presently the second most abundant HCFCs, after HCFC-22 (CHClF2). It is used in a wide range of applications, including as a blowing foam agent, in refrigeration and air-conditioning. Its concentration will soon reach 25 ppt in the northern hemisphere, with mixing ratios increasing at about 1.1 ppt/yr [Montzka et al., 2011]. The HCFC-142b lifetime is estimated at 18 years. With a global warming potential of 2310 on a 100-yr horizon, this species is also a potent greenhouse gas [Forster et al., 2007]. First space-based retrievals of HCFC-142b have been reported by Dufour et al. [2005]. 17 occultations recorded in 2004 by the Canadian ACE-FTS instrument (Atmospheric Chemistry Experiment - Fourier Transform Spectrometer, onboard SCISAT-1) were analyzed, using two microwindows (1132.5-1135.5 and 1191.5-1195.5 cm-1). In 2009, Rinsland et al. determined the HCFC-142b trend near the tropopause, from the analysis of ACE-FTS observations recorded over the 2004-2008 time period. The spectral region used in this study extended from 903 to 905.5 cm-1. In this contribution, we will present the first HCFC-142b measurements from ground-based high-resolution Fourier Transform Infrared (FTIR) solar spectra. We use observations recorded at the high altitude station of the Jungfraujoch (46.5°N, 8°E, 3580 m asl), with a Bruker 120HR instrument, in the framework of the Network for the Detection of Atmospheric Composition Change (NDACC, visit http://www.ndacc.org). The retrieval of HCFC-142b is very challenging, with simulations indicating only weak absorptions, lower than 1% for low sun spectra and current

  11. HIGH-RESOLUTION LABORATORY SPECTRA ON THE λ131 CHANNEL OF THE AIA INSTRUMENT ON BOARD THE SOLAR DYNAMICS OBSERVATORY

    SciTech Connect

    Träbert, Elmar; Beiersdorfer, Peter; Brickhouse, Nancy S.; Golub, Leon

    2014-03-01

    Extreme ultraviolet spectra of C, O, F, Ne, Si, S, Ar, Ca, Fe, and Ni have been excited in an electron beam ion trap and studied with much higher resolution than available on Solar Dynamics Observatory (SDO) in order to ascertain the spectral composition of the SDO observations. We presently show our findings in the wavelength range 124-134 Å, which encompasses the λ131 observation channel of the Atmospheric Imaging Assembly (AIA). While the general interpretation of the spectral composition of the λ131 Fe channel is being corroborated, a number of new lines have been observed that might help to improve the diagnostic value of the SDO/AIA data.

  12. IMAPS - A high-resolution, echelle spectrograph to record far-ultraviolet spectra of stars from sounding rockets

    NASA Technical Reports Server (NTRS)

    Jenkins, E. B.; Joseph, C. L.; Long, D.; Zucchino, P. M.; Carruthers, G. R.

    1988-01-01

    A novel sounding rocket payload consisting of a slitless objective grating spectrograph with no transmission elements in the optical train (or detector) is described. This instrument, called the interstellar medium absorption profile spectrograph (IMAPS), is designed to provide continuous coverage over the wavelength range of 950-1150 A; it has an effective collecting area of about 4 sq cm and can record spectra of pointlike sources at a wavelength resolution of 0.004 A and with a sample interval of 0.002 A. The successful use of this instrument aboard a Black Brant rocket is described.

  13. Infrared reflectance spectra (4-12 micron) of lunar samples

    NASA Technical Reports Server (NTRS)

    Nash, Douglas B.

    1991-01-01

    Presented here are infrared reflectance spectra of a typical set of Apollo samples to illustrate spectral character in the mid-infrared (4 to 12 microns) of lunar materials and how the spectra varies among three main forms: soil, breccia, and igneous rocks. Reflectance data, to a close approximation, are the inverse of emission spectra; thus, for a given material the spectral reflectance (R) at any given wavelength is related to emission (E) by 1 - R equals E. Therefore, one can use reflectance spectra of lunar samples to predict how emission spectra of material on the lunar surface will appear to spectrometers on orbiting spacecraft or earthbound telescopes. Spectra were measured in the lab in dry air using a Fourier Transform Infrared spectrometer. Shown here is only the key portion (4 to 12 microns) of each spectrum relating to the principal spectral emission region for sunlit lunar materials and to where the most diagnostic spectral features occur.

  14. Phase-modulated electronic wave packet interferometry reveals high resolution spectra of free Rb atoms and Rb*He molecules.

    PubMed

    Bruder, Lukas; Mudrich, Marcel; Stienkemeier, Frank

    2015-10-01

    Phase-modulated wave packet interferometry is combined with mass-resolved photoion detection to investigate rubidium atoms attached to helium nanodroplets in a molecular beam experiment. The spectra of atomic Rb electronic states show a vastly enhanced sensitivity and spectral resolution when compared to conventional pump-probe wave packet interferometry. Furthermore, the formation of Rb*He exciplex molecules is probed and for the first time a fully resolved vibrational spectrum for transitions between the lowest excited 5Π3/2 and the high-lying electronic states 2(2)Π, 4(2)Δ, 6(2)Σ is obtained and compared to theory. The feasibility of applying coherent multidimensional spectroscopy to dilute cold gas phase samples is demonstrated in these experiments. PMID:26309123

  15. Inter-pulse high-resolution gamma-ray spectra using a 14 MeV pulsed neutron generator

    USGS Publications Warehouse

    Evans, L.G.; Trombka, J.I.; Jensen, D.H.; Stephenson, W.A.; Hoover, R.A.; Mikesell, J.L.; Tanner, A.B.; Senftle, F.E.

    1984-01-01

    A neutron generator pulsed at 100 s-1 was suspended in an artificial borehole containing a 7.7 metric ton mixture of sand, aragonite, magnetite, sulfur, and salt. Two Ge(HP) gamma-ray detectors were used: one in a borehole sonde, and one at the outside wall of the sample tank opposite the neutron generator target. Gamma-ray spectra were collected by the outside detector during each of 10 discrete time windows during the 10 ms period following the onset of gamma-ray build-up after each neutron burst. The sample was measured first when dry and then when saturated with water. In the dry sample, gamma rays due to inelastic neutron scattering, neutron capture, and decay were counted during the first (150 ??s) time window. Subsequently only capture and decay gamma rays were observed. In the wet sample, only neutron capture and decay gamma rays were observed. Neutron capture gamma rays dominated the spectrum during the period from 150 to 400 ??s after the neutron burst in both samples, but decreased with time much more rapidly in the wet sample. A signal-to-noise-ratio (S/N) analysis indicates that optimum conditions for neutron capture analysis occurred in the 350-800 ??s window. A poor S/N in the first 100-150 ??s is due to a large background continuum during the first time interval. Time gating can be used to enhance gamma-ray spectra, depending on the nuclides in the target material and the reactions needed to produce them, and should improve the sensitivity of in situ well logging. ?? 1984.

  16. Infrared spectra of natural and synthetic malachites

    NASA Astrophysics Data System (ADS)

    Schuiskii, A. V.; Zorina, M. L.

    2013-09-01

    IR absorption and reflection spectra of dark and light samples of natural and synthetic malachite over 400-4000 cm-1 are studied for the purpose of improving the synthesis technique and in order to distinguish between natural malachite and malachite grown from ammonia solutions. Nitrogen was not detected in the IR spectra or in microprobe analyses of the synthetic material. The differences found in the IR spectra were insignificant and cannot be regarded as distinctive indicators of these materials.

  17. Measurements of Saharan Dust Extinction Spectra in the Infrared

    NASA Astrophysics Data System (ADS)

    Thomas, M.; Gautier, C.; Ricchiazzi, P.; Peterson, P.; Salustro, C.

    2006-12-01

    The infrared extinction spectra of Saharan dust obtained by the Portable Infrared Aerosol Transmission Experiment (PIRATE) are reported in this paper. Saharan dust extinction (optical thickness) spectra from 8 to 13 mm were obtained using solar occultation measurements at Mbour, Senegal in January and March 2006 using a Fourier Transform Infrared (FTIR) spectrometer. The FTIR measured the solar flux in the infrared in the presence of Saharan dust, and the optical thickness was determined by comparing the measured spectra to the modeled spectra without dust for the same solar zenith angle, water vapor concentration and ozone concentration. The modeled spectra were generated using the Santa Barbara Disort Atmospheric Radiative Transfer (SBDART) program. . The infrared optical thickness spectra is compared with modeled optical thickness spectra obtained using Mie theory and dust index of refraction from various sources with assumed log-normal size distributions. Results from these measurements may provide information for improving the remote detection of Saharan dust from space in the infrared using MODIS or AIRS.

  18. High-Resolution Ultraviolet Spectra of the Dwarf Seyfert 1 Galaxy NGC 4395: Evidence for Intrinsic Absorption

    NASA Astrophysics Data System (ADS)

    Crenshaw, D. M.; Kraemer, S. B.; Gabel, J. R.; Schmitt, H. R.; Filippenko, A. V.; Ho, L. C.; Shields, J. C.; Turner, T. J.

    2004-09-01

    We present ultraviolet spectra of the dwarf Seyfert 1 nucleus of NGC 4395, obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope Space Telescope Imaging Spectrograph at velocity resolutions of 7-15 km s-1. We confirm our earlier claim of C IV absorption in low-resolution UV spectra and detect a number of other absorption lines with lower ionization potentials. In addition to the Galactic lines, we identify two kinematic components of absorption that are likely to be intrinsic to NGC 4395. We consider possible origins of the absorption, including the interstellar medium (ISM) of NGC 4395, the narrow-line region, the outflowing UV absorbers, and the X-ray ``warm absorbers.'' Component 1, at a radial velocity of -770 km s-1 with respect to the nucleus, is only identified in the C IV λ1548.2 line. It most likely represents an outflowing UV absorber, similar to those seen in a majority of Seyfert 1 galaxies, although additional observations are needed to confirm the reality of this feature. Component 2, at -114 km s-1, most likely arises in the ISM of NGC 4395; its ionic column densities cannot be matched by photoionization models with a power-law continuum. Our models of the highly ionized X-ray absorbers claimed for this active galactic nucleus indicate that they would have undetectable C IV absorption, but large O VI and H I columns should be present. We attribute our lack of detection of the O VI and Lyβ absorption from the X-ray absorbers to a combination of noise and dilution of the nuclear spectrum by hot stars in the large FUSE aperture. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555 these observations are associated with proposal GO-9362. Also based on observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer

  19. A census of quasar-intrinsic absorption in the Hubble Space Telescope archive: systems from high-resolution echelle spectra

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib; Lynch, Ryan S.; Charlton, Jane C.; Eracleous, Michael; Tripp, Todd M.; Palma, Christopher; Sembach, Kenneth R.; Misawa, Toru; Masiero, Joseph R.; Milutinovic, Nikola; Lackey, Benjamin D.; Jones, Therese M.

    2013-10-01

    We present a census of zabs ≲ 2 intrinsic (those showing partial coverage) and associated (zabs ˜ zem) quasar absorption-line systems detected in the Hubble Space Telescope archive of Space Telescope Imaging Spectrograph echelle spectra. This work complements the Misawa et al. survey of 2 < zem < 4 quasars that selects systems using similar techniques. We confirm the existence of so-called strong N V intrinsic systems (where the equivalent width of H I Lyα is small compared to N V λ1238) presented in that work, but find no convincing cases of `strong C IV' intrinsic systems at low redshift/luminosity. Moreover, we also report on the existence of `strong O VI' systems. From a comparison of partial coverage results as a function of ion, we conclude that systems selected by the N V ion have the highest probability of being intrinsic. By contrast, the C IV and O VI ions are poor selectors. Of the 30 O VI systems tested, only two of the systems in the spectrum on 3C 351 show convincing evidence for partial coverage. However, there is an ˜3σ excess in the number of absorbers near the quasar redshift (|Δv| ≤ 5000 km s-1) over absorbers at large redshift differences. In at least two cases, the associated O VI systems are known not to arise close to the accretion disc of the quasar.

  20. The weakly bound He-HCCCN complex: High-resolution microwave spectra and intermolecular potential-energy surface

    NASA Astrophysics Data System (ADS)

    Topic, Wendy C.; Jäger, Wolfgang

    2005-08-01

    Rotational spectra of the weakly bound He-HCCCN and He-DCCCN van der Waals complexes were observed using a pulsed-nozzle Fourier-transform microwave spectrometer in the 7-26-GHz frequency region. Nuclear quadrupole hyperfine structures due to the N14 and D nuclei (both with nuclear-spin quantum number I =1) were resolved and assigned. Both strong a and weaker b-type transitions were observed and the assigned transitions were used to fit the parameters of a distortable asymmetric rotor model. The dimers are floppy, near T-shaped complexes. Three intermolecular potential-energy surfaces were calculated using the coupled-cluster method with single and double excitations and noniterative inclusion of triple excitations. Bound-state rotational energy levels supported by these surfaces were determined. The quality of the potential-energy surfaces was assessed by comparing the experimental and calculated transition frequencies and also the corresponding spectroscopic parameters. Simple scaling of the surfaces improved both the transition frequencies and spectroscopic constants. Five other recently reported surfaces [O. Akin-Ojo, R. Bukowski, and K. Szalewicz, J. Chem. Phys. 119, 8379 (2003)], calculated using a variety of methods, and their agreement with spectroscopic properties of He-HCCCN are discussed.

  1. Stratospheric N2O mixing ratio profile from high-resolution balloon-borne solar absorption spectra and laboratory spectra near 1880/cm

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Goldman, A.; Murcray, F. J.; Murcray, D. G.; Smith, M. A. H.; Seals, R. K., Jr.; Larsen, J. C.; Rinsland, P. L.

    1982-01-01

    A nonlinear least-squares fitting procedure is used to derive the stratospheric N2O mixing ratio profile from balloon-borne solar absorption spectra and laboratory spectra near 1880/cm. The atmospheric spectra analyzed here were recorded during sunset from a float altitude of 33 km with the University of Denver's 0.02/cm resolution interferometer near Alamogordo, N.M. (33 deg N) on Oct. 10, 1979. The laboratory data are used to determine the N2O line intensities. The measurements suggest an N2O mixing ratio of 264 ppbv near 15 km, decreasing to 155 ppbv near 28 km.

  2. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Venkataraman, Malathy Devi

    2003-01-01

    Spectroscopic parameters (such as line position, intensity, broadening and shifting coefficients and their temperature dependences, line mixing coefficients etc.) for various molecular species of atmospheric interest are determined. In order to achieve these results, infrared spectra of several molecular bands are obtained using high-resolution recording instruments such as tunable diode laser spectrometer and Fourier transform spectrometers. Using sophisticated analysis routines (Multispectrum nonlinear least squares technique) these high-resolution infrared spectra are processed to determine the various spectral line parameters that are cited above. Spectra were taken using the McMath-Pierce Fourier transform spectrometer (FTS) at the National Solar Observatory on Kitt Peak, Arizona as well as the Bruker FTS at the Pacific Northwest National Laboratory (PNNL) at Richland, Washington. Most of the spectra are acquired not only at room temperature, but also at several different cold temperatures. This procedure is necessary to study the variation of the spectral line parameters as a function of temperature in order to simulate the Earth's and other planetary atmospheric environments. Depending upon the strength or weakness of the various bands recorded and analyzed, the length(s) of the absorption cells in which the gas samples under study are kept varied from a few centimeters up to several meters and the sample temperatures varied from approximately +30 C to -63 C. Research on several infrared bands of various molecular species and their isotopomers are undertaken. Those studies are briefly described.

  3. A Sounding Rocket Mission Concept to Acquire High-Resolution Radiometric Spectra Spanning the 9 nm - 31 nm Wavelength Range

    NASA Technical Reports Server (NTRS)

    Krause, L. Habash; Cirtain, Jonathan; McGuirck, Michael; Pavelitz, Steven; Weber, Ed.; Winebarger, Amy

    2012-01-01

    When studying Solar Extreme Ultraviolet (EUV) emissions, both single-wavelength, two- dimensional (2D) spectroheliograms and multi-wavelength, one-dimensional (1D) line spectra are important, especially for a thorough understanding of the complex processes in the solar magnetized plasma from the base of the chromosphere through the corona. 2D image data are required for a detailed study of spatial structures, whereas radiometric (i.e., spectral) data provide information on relevant atomic excitation/ionization state densities (and thus temperature). Using both imaging and radiometric techniques, several satellite missions presently study solar dynamics in the EUV, including the Solar Dynamics Observatory (SDO), Hinode, and the Solar-Terrestrial Relations Observatory (STEREO). The EUV wavelengths of interest typically span 9 nm to 31 nm, with the shorter wavelengths being associated with the hottest features (e.g., intense flares and bright points) and the longer wavelengths associated with cooler features (e.g., coronal holes and filaments). Because the optical components of satellite instruments degrade over time, it is not uncommon to conduct sounding rocket underflights for calibration purposes. The authors have designed a radiometric sounding rocket payload that could serve as both a calibration underflight for and a complementary scientific mission to the upcoming Solar Ultraviolet Imager (SUVI) mission aboard the GOES-R satellite (scheduled for a 2015 launch). The challenge to provide quality radiometric line spectra over the 9-31 nm range covered by SUVI was driven by the multilayer coatings required to make the optical components, including mirrors and gratings, reflective over the entire range. Typically, these multilayers provide useful EUV reflectances over bandwidths of a few nm. Our solution to this problem was to employ a three-telescope system in which the optical components were coated with multilayers that spanned three wavelength ranges to cover

  4. High resolution CCD spectra of stars in globular clusters. Part 2: Metals and CNO in M71

    NASA Technical Reports Server (NTRS)

    Leep, E. M.; Oke, J. B.; Wallerstein, G.

    1986-01-01

    Palomar coude CCD spectra of resolution 0.3 and 0.6 has been used to redetermine abundances in five stars of the relatively metal rich globular cluster M71. The (Fe/H) value is restricted to the limits of -0.6 to -1.0. The largest source of uncertainty is a systematic difference in f-values between those derived via the Holweger-Muller (1974) solar model and the Bell et al. (1976) solar model. If we use absolute f-values measured by the Oxford group (Blackwell et al. 1982) we find Fe/H to lie in the range of -0.6 to -0.75, i.e., as given by using the Bell et al. solar model. The relative abundances of the light elements, i.e., Na through Ca and probably including Ti show an average excess relative to iron of 0.4 dex. The effect of this difference on metal indices derived from broad- and narrow- band photometry is discussed. For three stars we find O/H = -0.6 using absolute f-values. For CN an analysis of individual rotational lines of the 2-0 band of the red system yields lines in the (C/H,N/H) plane that are consistent with either an original C/Fe = N/Fe = 0 or a modest increase in N relative to C due to CN burning and mixing. A search for C-13N was not successful and an uncertain lower limit of C-12/C-13 near 10 was obtained.

  5. High-Resolution Synchrotron Infrared Spectroscopy of Thiophosgene: the νb{1}, νb{5}, 2νb{4}, and νb{2} + 2νb{6} bands

    NASA Astrophysics Data System (ADS)

    McKellar, Bob; Billinghurst, Brant E.

    2015-06-01

    Thiophosgene (Cl_2CS) is a favorite model system for studies of photophysics, vibrational dynamics, and intersystem interactions. But at high resolution its infrared spectrum is very congested due to hot bands and multiple isotopic species. Previously, we reported the first high resolution IR study of this molecule, analyzing the νb{2} (504 wn) and νb{4} (471 wn) fundamental bands. Here we continue, with analysis of the νb{1} (1139 wn) and νb{5} (820 wn) fundamentals for the two most abundant isotopologues, 35Cl2CS and 35Cl37ClCS, based on spectra with a resolution of about 0.001 wn obtained at the Canadian Light Source far-infrared beamline using synchrotron radiation and a Bruker IFS125 Fourier transform spectrometer. The νb{2} + νb{4} (942 wn) and νb{2} + 2νb{6} (1104 wn) bands are also studied here. But so far the νb{2} + νb{6} combination band (795 wn) resists analysis, as do the weak νb{3} (292.9 wn) and νb{6} (≈300? wn) fundamentals. A.R.W. McKellar, B.E.Billinghurst, J. Mol. Spectrosc. 260, 66 (2010).

  6. High resolution FTIR spectra and analysis of the ν 4 hot band of CH 2 35 Cl 2

    NASA Astrophysics Data System (ADS)

    Snels, Marcel; D'Amico, Giuseppe

    The infrared spectrum of isotopically pure CH235Cl2 has been recorded at a resolution of 0.0032 cm-Cl2 has been recorded at a resolution of 0.0032 cm-1 (FWHM) in the range 1400-1600 cm--1 (FWHM) in the range 1400-1600 cm-11 with a Bruker IFS 120 HR Fourier transform spectrometer in Wuppertal. Here we report the full rotational analysis of the ν4 + ν8 combination band and the ν4 + ν8- ν4 hot band, which are essentially unperturbed. Excited state constants up to quartic terms have been obtained for both bands and anharmonicity constants involving ν4 and ν8 have been determined. An accurate value for the ν4 band origin has been determined from the ν4 + ν8 combination band and the ν4 + ν8 - ν4 hot band, and successively the anharmonicity constants χ48 , χ34 , χ49 and χ44 were calculated from hot bands observed in this and previous works. For the CH23-11 with a Bruker IFS 120 HR Fourier transform spectrometer in Wuppertal. Here we report the full rotational analysis of the ν4 + ν8 combination band and the ν4 + ν8- ν4 hot band, which are essentially unperturbed. Excited state constants up to quartic terms have been obtained for both bands and anharmonicity constants involving ν4 and ν8 have been determined. An accurate value for the ν4 band origin has been determined from the ν4 + ν8 combination band and the ν4 + ν8 - ν4 hot band, and successively the anharmonicity constants χ48 , χ34 , χ49 and χ44 were calculated from hot bands observed in this and previous works. For the CH235 Cl335 Cl37 Cl isotopic species, band origins for ν4 , &ngr4 + ν8 and 2ν4 + ν8 have been obtained, by assuming the same anharmonicity constants as for CH2337 Cl isotopic species, band origins for ν4 , &ngr4 + ν8 and 2ν4 + ν8 have been obtained, by assuming the same anharmonicity constants as for CH235 Cl2 .

  7. A high resolution far-infrared survey of a section of the galactic plane. I - The nature of the sources

    NASA Technical Reports Server (NTRS)

    Jaffe, D. T.; Stier, M. T.; Fazio, G. G.

    1982-01-01

    Far-infrared, radio continuum and (C-12)O and (C-13)O line observations are presented of 42 far-infrared sources. The sources range in luminosity from 4000 to 3,000,000 solar luminosities. Most of them are associated with (C-12)O peaks. More than half the sources have associated H2O maser emission, and half possess associated radio continuum emission at a limit of 100 mJy. Eight have radio emission at weaker levels. In many cases, the far-infrared source is smaller than its associated radio source. The difference can be explained in the context of the 'blister' picture of H II regions. One group of sources emits many fewer Lyman continuum photons than expected, considering the far-infrared luminosities. A number of possible reasons for this are examined; the explanation holding that clusters of early type stars rather than single stars excite the far-infrared sources is considered the most reasonable.

  8. Multivariate classification of infrared spectra of cell and tissue samples

    DOEpatents

    Haaland, David M.; Jones, Howland D. T.; Thomas, Edward V.

    1997-01-01

    Multivariate classification techniques are applied to spectra from cell and tissue samples irradiated with infrared radiation to determine if the samples are normal or abnormal (cancerous). Mid and near infrared radiation can be used for in vivo and in vitro classifications using at least different wavelengths.

  9. Applications and limitations of constrained high-resolution peak fitting on low resolving power mass spectra from the ToF-ACSM

    NASA Astrophysics Data System (ADS)

    Timonen, Hilkka; Cubison, Mike; Aurela, Minna; Brus, David; Lihavainen, Heikki; Hillamo, Risto; Canagaratna, Manjula; Nekat, Bettina; Weller, Rolf; Worsnop, Douglas; Saarikoski, Sanna

    2016-07-01

    The applicability, methods and limitations of constrained peak fitting on mass spectra of low mass resolving power (m/Δm50 ˜ 500) recorded with a time-of-flight aerosol chemical speciation monitor (ToF-ACSM) are explored. Calibration measurements as well as ambient data are used to exemplify the methods that should be applied to maximise data quality and assess confidence in peak-fitting results. Sensitivity analyses and basic peak fit metrics such as normalised ion separation are employed to demonstrate which peak-fitting analyses commonly performed in high-resolution aerosol mass spectrometry are appropriate to perform on spectra of this resolving power. Information on aerosol sulfate, nitrate, sodium chloride, methanesulfonic acid as well as semi-volatile metal species retrieved from these methods is evaluated. The constants in a commonly used formula for the estimation of the mass concentration of hydrocarbon-like organic aerosol may be refined based on peak-fitting results. Finally, application of a recently published parameterisation for the estimation of carbon oxidation state to ToF-ACSM spectra is validated for a range of organic standards and its use demonstrated for ambient urban data.

  10. High-resolution UVES/VLT spectra of white dwarfs observed for the ESO SN Ia Progenitor Survey. III. DA white dwarfs

    NASA Astrophysics Data System (ADS)

    Koester, D.; Voss, B.; Napiwotzki, R.; Christlieb, N.; Homeier, D.; Lisker, T.; Reimers, D.; Heber, U.

    2009-10-01

    Context: The ESO Supernova Ia Progenitor Survey (SPY) took high-resolution spectra of more than 1000 white dwarfs and pre-white dwarfs. About two thirds of the stars observed are hydrogen-dominated DA white dwarfs. Here we present a catalog and detailed spectroscopic analysis of the DA stars in the SPY. Aims: Atmospheric parameters effective temperature and surface gravity are determined for normal DAs. Double-degenerate binaries, DAs with magnetic fields or dM companions, are classified and discussed. Methods: The spectra are compared with theoretical model atmospheres using a χ2 fitting technique. Results: Our final sample contains 615 DAs, which show only hydrogen features in their spectra, although some are double-degenerate binaries. 187 are new detections or classifications. We also find 10 magnetic DAs (4 new) and 46 DA+dM pairs (10 new). Based on data obtained at the Paranal Observatory of the European Southern Observatory for programmes 165.H-0588 and 167.D-0407.

  11. A Cryogenic, Insulating Suspension System for the High Resolution Airborne Wideband Camera (HAWC)and Submillemeter And Far Infrared Experiment (SAFIRE) Adiabatic Demagnetization Refrigerators (ADRs)

    NASA Technical Reports Server (NTRS)

    Voellmer, George M.; Jackson, Michael L.; Shirron, Peter J.; Tuttle, James G.

    2002-01-01

    The High Resolution Airborne Wideband Camera (HAWC) and the Submillimeter And Far Infrared Experiment (SAFIRE) will use identical Adiabatic Demagnetization Refrigerators (ADR) to cool their detectors to 200mK and 100mK, respectively. In order to minimize thermal loads on the salt pill, a Kevlar suspension system is used to hold it in place. An innovative, kinematic suspension system is presented. The suspension system is unique in that it consists of two parts that can be assembled and tensioned offline, and later bolted onto the salt pill.

  12. Effects of Forsterite Grain Shape on Infrared Spectra

    NASA Astrophysics Data System (ADS)

    Koike, C.; Imai, Y.; Chihara, H.; Suto, H.; Murata, K.; Tsuchiyama, A.; Tachibana, S.; Ohara, S.

    2010-02-01

    The Infrared Space Observatory (ISO) detected several sharp infrared features around young stars, comets, and evolved stars. These sharp features were identified as Mg-rich crystalline silicates of forsterite and enstatite by comparison with spectra from laboratory data. However, certain infrared emission bands in the observed spectra cannot be identified because they appear at slightly shorter wavelengths than the peaks in forsterite laboratory spectra, where the shapes of forsterite particles are irregular. To solve this problem, we measured infrared spectra of forsterite grains of various shapes (irregular, plate-like with no sharp edges, elliptical, cauliflower, and spherical) in the infrared spectral region between 5 and 100 μm. The spectra depend on particle shape. The spectra of the 11, 19, 23, and 33 μm bands, in particular, are extremely sensitive to particle shape, whereas some peaks such as the 11.9, 49, and 69 μm bands remained almost unchanged despite different particle shapes. This becomes most evident from the spectra of near-spherical particles produced by annealing an originally amorphous silicate sample at temperature from 600 to 1150°C. The spectra of these samples differ strongly from those of other ones, showing peaks at much shorter wavelengths. At a higher annealing temperature of 1200°C, the particle shapes changed drastically from spherical to irregular and the spectra became similar to those of forsterite particles with irregular shapes. Based on ISO data and other observational data, the spectra of outflow sources and disk sources may correspond to differences in forsterite shape, and further some unidentified peaks, such as those at 32.8 or 32.5 μm, may be due to spherical or spherical-like forsterite.

  13. EFFECTS OF FORSTERITE GRAIN SHAPE ON INFRARED SPECTRA

    SciTech Connect

    Koike, C.; Imai, Y.; Chihara, H.; Murata, K.; Tsuchiyama, A.; Suto, H.; Tachibana, S.; Ohara, S.

    2010-02-01

    The Infrared Space Observatory (ISO) detected several sharp infrared features around young stars, comets, and evolved stars. These sharp features were identified as Mg-rich crystalline silicates of forsterite and enstatite by comparison with spectra from laboratory data. However, certain infrared emission bands in the observed spectra cannot be identified because they appear at slightly shorter wavelengths than the peaks in forsterite laboratory spectra, where the shapes of forsterite particles are irregular. To solve this problem, we measured infrared spectra of forsterite grains of various shapes (irregular, plate-like with no sharp edges, elliptical, cauliflower, and spherical) in the infrared spectral region between 5 and 100 mum. The spectra depend on particle shape. The spectra of the 11, 19, 23, and 33 mum bands, in particular, are extremely sensitive to particle shape, whereas some peaks such as the 11.9, 49, and 69 mum bands remained almost unchanged despite different particle shapes. This becomes most evident from the spectra of near-spherical particles produced by annealing an originally amorphous silicate sample at temperature from 600 to 1150 deg. C. The spectra of these samples differ strongly from those of other ones, showing peaks at much shorter wavelengths. At a higher annealing temperature of 1200 deg. C, the particle shapes changed drastically from spherical to irregular and the spectra became similar to those of forsterite particles with irregular shapes. Based on ISO data and other observational data, the spectra of outflow sources and disk sources may correspond to differences in forsterite shape, and further some unidentified peaks, such as those at 32.8 or 32.5 mum, may be due to spherical or spherical-like forsterite.

  14. Mid-infrared high-resolution absorption spectroscopy by use of a semimonolithic entangled-cavity optical parametric oscillator.

    PubMed

    Desormeaux, A; Lefebvre, M; Rosencher, E; Huignard, J P

    2004-12-15

    By recording low-pressure absorption lines of N2O around 3.9 microm, we fully qualify a pulsed entangled-cavity doubly resonant optical parametric oscillator as a power tool for high-resolution spectroscopy. This compact source runs at a high repetition rate (>10 kHz) with a low threshold of oscillation (<8 microJ), is mode-hop-free tunable over 5 cm(-1), and displays single-frequency Fourier-transformed-limited operation (linewidth <0.005 cm(-1)). A high potential for nonlinear spectroscopy is also expected given the high peak power (70 W) and the good quality (M2 < 2) of the output beam. PMID:15645813

  15. High Resolution Far Infrared Study of Antiferromagnetic Resonance Transitions in α-Fe2O3 (hematite)

    NASA Astrophysics Data System (ADS)

    Chou, Shin Grace; Plusquellic, David F.; Stutzman, Paul E.; Wang, Shuangzhen; Garboczi, Edward J.; Egelhoff, William F.

    2012-02-01

    In this study, we report high resolution optical measurements of the temperature dependence of the antiferromagnetic (AFM) transition in α-Fe2O3 (hematite) between (0.5 and 10) cm-1. The absorption peak position, over a large temperature range, is found to be in agreement with a modified spin-wave model at both the high and low temperature phases, where the temperature is above and below the Morin transition temperature, respectively. The high spectral resolution optical measurements as demonstrated in this study allow unprecedented zero-field spectral analysis of the zone center AFM magnon in a previously challenging spectral region, giving insights into the role of temperature and strain on the exchange and anisotropy interactions in the system. The results also suggest that the frequency-resolved measurement platform could be extended for room-temperature non-destructive examination and imaging applications for antiferromagnetic materials and devices.

  16. Effects of atmosphere and view and illumination geometry on visible and near infrared radiance data from the advanced very high resolution radiometer (AVHR)

    NASA Technical Reports Server (NTRS)

    Holben, B. N.; Fraser, R. S.

    1984-01-01

    The use of Dave's models to evaluate satellite off-nadir remote sensing of green vegetation cover types by simulating the visible and near-infrared advanced very high resolution radiometer (AVHRR) NOAA-6 and NOAA-7 radiances for three green-leaf biomass levels and bare soil. Ground measurements of surface reflectances were used. The simulations were done along a scan line at 30 deg latitude during the summer solstice, equinox, and winter solstice. The simulation models are described and the effect of atmosphere over moderately vegetated surfaces is discussed. The results show that sensor response to atmospheric path length can be substantial for the AVHRR visible and near-infrared channels and normalized difference values, but they can be minimized by high sun and clear atmospheric viewing. The results indicate that AVHRR data would be most useful for monitoring low green leaf biomas canopies.

  17. HIGH-RESOLUTION FOURIER TRANSFORM INFRARED SPECTRUM OF THE ν2 + ν12 BAND OF ETHYLENE (12C2H4)

    NASA Astrophysics Data System (ADS)

    Lebron, G. B.; Tan, T. L.

    2013-09-01

    The high-resolution Fourier transform infrared absorption spectrum of the ν2 + ν12 combination band of normal ethylene (12C2H4) in the 3050-3105 cm-1 region was recorded at a resolution of 0.0063 cm-1 and at an ambient temperature of 296 K. Upper state rovibrational analysis was carried out using a standard Watson's Hamiltonian in asymmetric reduction in Ir representation. The band center, rotational constants and centrifugal distortion constants up to quartic terms of the upper ν2 + ν12 = 1 state were determined from the final fit that included 102 infrared transitions. The root-mean-square deviation of the fit was 0.000729 cm-1.

  18. A high-resolution mid-infrared spectral survey of H2O in the circumstellar envelope of VY CMa with EXES on SOFIA

    NASA Astrophysics Data System (ADS)

    DeWitt, Curtis N.; Richter, Matthew; Fonfría, José; Cernicharo, Jose; Neufeld, David A.; Boogert, Adwin

    2015-08-01

    During March 2015 commissioning observations, the EXES instrument on the Stratospheric Observatory for Infrared Astronomy (SOFIA), observed the O-rich evolved star VY Cyg in the range of 5.57 to 6.67 μm with a resolution (R=λ/Δλ) approaching 100,000.We detect many H2O vapor lines with P Cygni structure- blueshifted absorption with redshifted emission, as expected from outflowing material in this system. The analysis and identification of other chemical species within this rich data set are ongoing.The wavelength region of these observations is impossible to observe from ground-based observatories due to atmospheric absorption; past space-based missions such as ISO/SWS were limited to R~1000. EXES on SOFIA opens a new frontier for high-resolution spectroscopy at difficult-to-access mid-infrared wavelengths.

  19. High-resolution X-ray spectra of solar flares. III - General spectral properties of X1-X5 type flares

    NASA Technical Reports Server (NTRS)

    Doschek, G. A.; Feldman, U.; Kreplin, R. W.; Cohen, L.

    1980-01-01

    High-resolution X-ray spectra of six class X1-X5 solar flares are discussed. The spectra were recorded by spaceborne Bragg crystal spectrometers in the ranges 1.82-1.97, 2.98-3.07 and 3.14-3.24 A. Electron temperatures derived from dielectronic satellite line to resonance line ratios for Fe XXV and Ca XIX are found to remain fairly constant around 22,000,000 and 16,000,000 K respectively during the rise phase of the flares, then decrease by approximately 6,000,000 K during the decay phase. Nonthermal motions derived from line widths for the April 27, 1979 event are found to be greatest during the rise phase (approximately 130 km/sec) and decrease to about 60 km/sec during decay. Volume emission measures for Fe XXV, Ca XIX and Ca XX are derived from photon fluxes as a function of temperature, and examination of the intensity behavior of the Fe K alpha emission as a function of time indicates that it is a result of fluorescence. Differences between the present and previous observations of temperature variation are discussed, and it is concluded that the flare plasmas are close to ionization equilibrium for the flares investigated.

  20. Feature Point Descriptors: Infrared and Visible Spectra

    PubMed Central

    Ricaurte, Pablo; Chilán, Carmen; Aguilera-Carrasco, Cristhian A.; Vintimilla, Boris X.; Sappa, Angel D.

    2014-01-01

    This manuscript evaluates the behavior of classical feature point descriptors when they are used in images from long-wave infrared spectral band and compare them with the results obtained in the visible spectrum. Robustness to changes in rotation, scaling, blur, and additive noise are analyzed using a state of the art framework. Experimental results using a cross-spectral outdoor image data set are presented and conclusions from these experiments are given. PMID:24566634

  1. Infrared spectra of substituted polycylic aromatic hydrocarbons

    NASA Technical Reports Server (NTRS)

    Langhoff, S. R.; Bauschlicher, C. W. Jr; Hudgins, D. M.; Sandford, S. A.; Allamandola, L. J.

    1998-01-01

    Calculations are carried out using density functional theory (DFT) to determine the harmonic frequencies and intensities of 1-methylanthracene, 9-methylanthracene, 9-cyanoanthracene, 2-aminoanthracene, acridine, and their positive ions. The theoretical data are compared with matrix-isolation spectra for these species also reported in this work. The theoretical and experimental frequencies and relative intensities for the neutral species are in generally good agreement, whereas the positive ion spectra are only in qualitative agreement. Relative to anthracene, we find that substitution of a methyl or CN for a hydrogen does not significantly affect the spectrum other than to add the characteristic methyl C-H and C triple bond N stretches near 2900 and 2200 cm-1, respectively. However, addition of NH2 dramatically affects the spectrum of the neutral. Not only are the NH2 modes themselves strong, but this electron-withdrawing group induces sufficient partial charge on the ring to give the neutral molecule spectra characteristics of the anthracene cation. The sum of the absolute intensities is about four times larger for 2-aminoanthracene than those for 9-cyanoanthracene. Substituting nitrogen in the ring at the nine position (acridine) does not greatly alter the spectrum compared with anthracene.

  2. Analysis of the high-resolution infrared spectrum of the ν2 bending mode of HOCl at 1238 cm -1

    NASA Astrophysics Data System (ADS)

    Sams, R. L.; Olson, W. B.

    1980-11-01

    The infrared spectrum of hypochlorous acid (HOCl) is investigated in the 1238-cm -1 ( ν2) region with a recently completed 3.81-m Ebert Spectrometer. A description of this instrument is included. Spectroscopic constants for ν2 are obtained.

  3. Experimental Transmission Spectra of Hot Ammonia in the Infrared

    NASA Astrophysics Data System (ADS)

    Beale, Christopher A.; Hargreaves, Robert J.; Dulick, Michael; Bernath, Peter F.

    2015-06-01

    High resolution absorption spectra of hot ammonia have been recorded in the 2400--5500 cm-1 region and the line lists are presented. This extends our previous work on ammonia in the 740--4000 cm-1 region and utilizes our improved cell design that has been successfully applied to methane in a similar spectral region. Transmission spectra were acquired for seven temperatures up to 700°C using a Bruker IFS 125HR Fourier transform spectrometer and empirical lower state energies are obtained from the temperature dependence of intensities. Applications of our spectra and line lists include modeling of brown dwarfs and (exo)planetary atmospheres. R.J. Hargreaves, G. Li and P.F. Bernath. 2011, ApJ, 735, 111 R.J. Hargreaves, G. Li and P.F. Bernath. 2011, JQSRT, 113, 670

  4. The High Resolution Infrared Spectrum of CH 3D in the Region 900-1700 cm -1

    NASA Astrophysics Data System (ADS)

    Nikitin, A.; Champion, J. P.; Tyuterev, Vl. G.; Brown, L. R.

    1997-07-01

    The high resolution absorption spectrum of CH3D in the region 900-1700 cm-1has been reexamined on the basis of new long path experimental data recorded with the Fourier transform spectrometer at Kitt Peak. A theoretical model used previously for spherical rotors has been adapted for symmetric top molecules in order to analyze the vibrational polyads of CH3D simultaneously. Both triad and nonad-triad band systems have been investigated. The hot band intensities were estimated through direct extrapolation of the triad dipole moments. Six hundred lines from the hot bands have been assigned and combined with other data for the triad. The main hot bands contributions are due to 2ν6- ν6, 2ν3- ν3, ν3+ ν6- ν3and ν3+ ν6- ν6bands. The standard deviation achieved for 3377 line positions of the triad was 0.56 10-3cm-1, representing an improvement of one order of magnitude with respect to the most recent analysis.

  5. A high-resolution infrared spectrum of IRC +10216. [carbon star immersed in expanding gas/dust shell

    NASA Technical Reports Server (NTRS)

    Barnes, T. G.; Hinkle, K. H.; Lambert, D. L.; Beer, R.

    1977-01-01

    The IR-emitting core and shell of IRC +10216 are investigated using a high-resolution spectrum covering the wavelength interval between 3 and 5 microns. Line identifications made or confirmed include those due to (C-12)(O-16), (C-13)(O-16), (C-12)(O-17), and (C-12)(O-18). A mean heliocentric velocity of about -32 km/s is obtained from the 42 least blended (C-12)O and (C-13)O lines, and the following isotopic abundance ratios are derived by comparing equivalent widths of the observed lines: C-12/C-13, C-12/C-14, O-16/O-17, and O-17/O-18. The structure of the expanding gas shell is examined, an explanation is offered for the lack of P Cygni profiles in the spectrum, and an unsuccessful search for other molecules is briefly discussed. It is concluded that a low C-12/C-13 ratio is not necessarily a signature of a carbon star.

  6. ATIRS package: A program suite for the rovibrational analysis of infrared spectra of asymmetric top molecules

    NASA Astrophysics Data System (ADS)

    Tasinato, N.; Pietropolli Charmet, A.; Stoppa, P.

    2007-06-01

    Nowadays high-resolution infrared spectra can be recorded quite easily and therefore it has become important to assist the rovibrational analysis, especially the assignment step, that is still fraught with many problems in the presence of perturbation effects. In this article we provide a description of ATIRS, a complete software suite developed for assisting in the rotational investigation of vibrational bands of asymmetric top molecules. This package uses the Pickett's CALPGM suite for fitting transitions and predicting line positions and is composed by three stand-alone applications: (1) Visual Loomis-Wood for the assignment of spectral lines based on Loomis-Wood type diagrams; (2) Visual CALPGM, a new graphical interface to Pickett's programs SPFIT and SPCAT; (3) Visual Spectra Simulator for the simulation of spectra. The graphical interface to the CALPGM suite is developed for asymmetric rotors. The main feature of this application is to avoid the use of the parameter codes that are here replaced employing the well known parameter names or symbols. Highlighting the regular transition sequences, Visual Loomis-Wood assists in the assignment of the spectral lines. It visualizes the description of a transition and the assignment can be simply done by mouse-clicking on the diagram; moreover its display mode feature lets to check the experimental spectrum in which all the assigned lines together with their description are reported. Visual Spectra Simulator provides a simple and functionally application that, using the calculated frequencies and intensities given by SPCAT, simulates the high-resolution infrared spectrum and compare it to the experimental one. ATIRS, freely available to the spectroscopic community, is designed to be easy to use and presents a standard graphical interface; being based on the CALPGM package it can handle forbidden transitions and perturbations among many states.

  7. Variability of SO2 and HDO at the cloudtop of Venus from high-resolution infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Encrenaz, T.; Greathouse, T.; Richter, M.; DeWitt, C.; Lacy, J.; Widemann, T.; Bézard, B.; Fouchet, T.; Atreya, S.; Sagawa, H.

    2015-10-01

    Since January 2012, we have mapped the SO2 and HDO mixing ratios at the cloudtop of Venus using the Texas Echelon Cross Echelle Spectrograph (TEXES) at the Infrared Telescope Fac ility (IRTF). The HDO maps appear homogeneous over the Venus disk. In contrast, the SO2 maps show strong variations over the disk and within a time scale of two hours. Both molecules show longterm variations with no apparent correlation between the two species.

  8. Applying 'Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra' (SWATH) for systematic toxicological analysis with liquid chromatography-high-resolution tandem mass spectrometry.

    PubMed

    Arnhard, Kathrin; Gottschall, Anna; Pitterl, Florian; Oberacher, Herbert

    2015-01-01

    Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become an indispensable analytical technique in clinical and forensic toxicology for detection and identification of potentially toxic or harmful compounds. Particularly, non-target LC-MS/MS assays enable extensive and universal screening requested in systematic toxicological analysis. An integral part of the identification process is the generation of information-rich product ion spectra which can be searched against libraries of reference mass spectra. Usually, 'data-dependent acquisition' (DDA) strategies are applied for automated data acquisition. In this study, the 'data-independent acquisition' (DIA) method 'Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra' (SWATH) was combined with LC-MS/MS on a quadrupole-quadrupole-time-of-flight (QqTOF) instrument for acquiring informative high-resolution tandem mass spectra. SWATH performs data-independent fragmentation of all precursor ions entering the mass spectrometer in 21m/z isolation windows. The whole m/z range of interest is covered by continuous stepping of the isolation window. This allows numerous repeat analyses of each window during the elution of a single chromatographic peak and results in a complete fragment ion map of the sample. Compounds and samples typically encountered in forensic casework were used to assess performance characteristics of LC-MS/MS with SWATH. Our experiments clearly revealed that SWATH is a sensitive and specific identification technique. SWATH is capable of identifying more compounds at lower concentration levels than DDA does. The dynamic range of SWATH was estimated to be three orders of magnitude. Furthermore, the >600,000 SWATH spectra matched led to only 408 incorrect calls (false positive rate = 0.06 %). Deconvolution of generated ion maps was found to be essential for unravelling the full identification power of LC-MS/MS with SWATH. With the available software, however, only semi

  9. INFRARED SPECTRA OF AMMONIA-WATER ICES

    SciTech Connect

    Zheng Weijun; Jewitt, David; Kaiser, Ralf I. E-mail: ralfk@hawaii.edu

    2009-03-15

    We conducted a systematic study of the near-IR and mid-IR spectra of ammonia-water ices at various NH{sub 3}/H{sub 2}O ratios. The differences between the spectra of amorphous and crystalline ammonia-water ices were also investigated. The 2.0 {mu}m ammonia band central wavelength is a function of the ammonia/water ratio. It shifts from 2.006 {+-} 0.003 {mu}m (4985 {+-} 5 cm{sup -1}) to 1.993 {+-} 0.003 {mu}m (5018 {+-} 5 cm{sup -1}) as the percentage of ammonia decreases from 100% to 1%. The 2.2 {mu}m ammonia band center shifts from 2.229 {+-} 0.003 {mu}m (4486 {+-} 5 cm{sup -1}) to 2.208 {+-} 0.003 {mu}m (4528 {+-} 5 cm{sup -1}) over the same range. Temperature-dependent shifts of those bands are below the uncertainty of the measurement, and therefore are not detectable. These results are important for comparison with astronomical observations as well as for estimating the concentration of ammonia in outer solar system ices.

  10. Infrared Spectra of Substituted Polycyclic Aromatic Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Hudgins, Douglas M.; Sandford, Scott A.; Allamandola, Louis J.; Arnold, James O. (Technical Monitor)

    1997-01-01

    Calculations are carried out using density functional theory (DFT) to determine the harmonic frequencies and intensities of 1-methylanthracene, 9-methylanthracene, 9-cyanoanthracene, 2-aminoanthracene, acridine, and their positive ions. The theoretical data are compared with matrix-isolation spectra for these species also reported in this work. The theoretical and experimental frequencies and relative intensities for the neutral species are in generally good agreement, whereas the positive ion spectra are only in qualitative agreement. Relative to anthracene, we find that substitution of amethyl or CN for a hydrogen does not significantly affect the spectrum other than to add the characteristic methyl C-H stretch and C-N stretch (near 2200/cm), respectively. However, addition of NH2 dramatically affects the spectrum of the neutral. Not only are the NH2 modes themselves strong, but this electron withdrawing group induces sufficient partial charge on the ring to give the neutral molecule characteristics of the anthracene cation spectrum. The sum of the absolute intensities is about four times larger for 2-aminoanthracene than for 9-cyanoanthracene. Substituting nitrogen in the ring at the nine position (acridine) does not greatly alter the spectrum compared with anthracene.

  11. Analysis of fingerprints features of infrared spectra of various processed products of Radix Aconiti kusnezoffii

    NASA Astrophysics Data System (ADS)

    Tu-ya; Yang, Ping; Sun, Su-qin; Zhou, Qun; Bao, Xiao-hua; Noda, Isao

    2010-06-01

    Fourier-transform infrared spectroscopy (FTIR) and two-dimensional correlation infrared spectroscopy (2D-IR)) are employed to analyze various processed products and ether extracts of Radix Aconiti kusnezoffii. There is a resemblance among the spectra of different processed products. The major difference lies in the absorption peak at 1641 cm -1 in the IR spectra, which reflects the transformation of raw aconite to the processed products. There are distinctive differences in the absorption peaks in the range of 1800-1500 cm -1 in the second derivative spectra, which has better resolution, of different processed products. 2D-IR spectra, which elevate the resolution further, can present even more differences among the products in the range of 1800-800 cm -1. Analysis of ether extracts of various processed products proves that there are alcohols, esters, carboxylic acids or ketones in all of them. However, their contents in different samples have obvious differences. With the advantages of high resolution, high-speed and convenience, IR can quickly and precisely distinguish various processed products of Radix A. kusnezoffii, and can be applied to predict the tendency of transformation of the complicated chemical mixture systems under heat perturbation.

  12. High-resolution synchrotron infrared spectroscopy of acrolein: The vibrational levels between 850 and 1020 cm-1

    NASA Astrophysics Data System (ADS)

    McKellar, A. R. W.; Billinghurst, B. E.; Xu, Li-Hong; Lees, R. M.

    2015-11-01

    Using spectra obtained at the Canadian Light Source synchrotron radiation facility, a previously unobserved out-of-plane vibration of trans-acrolein (propenal) is reliably assigned for the first time. Its origin is at 1002.01 cm-1, which is about 20 cm-1 higher than usually quoted in the past. This mode is thus labelled as v14, leaving the label v15 for the known vibration at 992.66 cm-1. Weak combination bands 171182 ← 182, 171131 ← 131, 121182 ← 181, and 171182 ← 181 are studied for the first time, and assignments in the known v11, v16, and v15 fundamental bands are also extended. The seven excited vibrations involved in these bands are analyzed, together with five more unobserved vibrations in the same region (850-1020 cm-1), in a large 12-state simultaneous fit which accounts for most of the many observed perturbations in the spectra.

  13. First results from IRENI - Rapid diffraction-limited high resolution imaging across the mid-infrared bandwidth

    SciTech Connect

    Nasse, Michael J.; Mattson, Eric; Hirschmugl, Carol

    2010-02-03

    First results from IRENI, a new beamline at the Synchrotron Radiation Center, demonstrate that synchrotron chemical imaging, which combines the characteristics of bright, stable, broadband synchrotron source with a multi-element detector, produces diffraction-limited images at all wavelengths simultaneously. A single cell of Micrasterias maintained in a flow cell has been measured, and results show high quality spectra and images demonstrating diffraction limited, and therefore wavelength-dependent, spatial resolution.

  14. Effect of pressure on infrared-spectra of ice VII

    NASA Technical Reports Server (NTRS)

    Holzapfel, W. B.; Seiler, B.; Nicol, M.

    1984-01-01

    The effect of pressure on the infrared spectra of H20 and D20 ice VII was studied at room temperature and at pressures between 2 and 15 GPa with a Fourier transform infrared spectrometer and a diamond anvil high pressure cell. Two librational modes, one bending mode, and various overtone bands are well resolved. The stretching modes, nu sub 1 and nu sub 3, are poorly resolved due to overlap with diamond window absorption. Differences between the spectra of H20 and D20 are discussed. Previously announced in STAR as N83-23671

  15. Effect of pressure on infrared spectra of ice 7

    NASA Technical Reports Server (NTRS)

    Holzapfel, W. B.; Seiler, B.; Nicol, M.

    1983-01-01

    The effect of pressure on the infrared spectra of H2O and D2O ice VII was studied at room temperature and pressures between 2 and 15 GPa with a Fourier transform infrared spectrometer and a diamond anvil high pressure cell. Two librational modes, one bending mode, and various overtone bands are well resolved. The stretching modes, nu sub 1 and nu sub 3 are poorly resolved due to overlap with diamond window absorption. Differences between the spectra of H2O and D2O are discussed.

  16. Evolution and infrared spectra of brown dwarfs

    NASA Technical Reports Server (NTRS)

    Lunine, Jonathan I.; Hubbard, William B.; Marley, Mark S.

    1986-01-01

    Self-consistent models are constructed for the structure, evolution, and observable properties of degenerately cooling objects, or 'brown dwarfs'. Model atmospheres composed of a range of likely gaseous and particulate opacity sources are calculated in order to provide a boundary condition for interior temperature-pressure profiles and to determine the emergent spectra for such objects. The radius derived from the interior models is combined with the emergent fluxes calculated from the atmosphere model to fit the data of McCarthy, Probst, and Low (1985) and to derive the luminosity and mass of VB 8B. The latter is found to be most probably an 0.05 solar mass object with effective temperature in the 1200-1500 K range and an atmosphere which very likely contains particulate absorbers. Key changes in chemical oxidation state and condensation of major constituents during the evolution of brown dwarfs are presented.

  17. Infrared spectra of jennite and tobermorite from first-principles

    SciTech Connect

    Vidmer, Alexandre Sclauzero, Gabriele; Pasquarello, Alfredo

    2014-06-01

    The infrared absorption spectra of jennite, tobermorite 14 Å, anomalous tobermorite 11 Å, and normal tobermorite 11 Å are simulated within a density-functional-theory scheme. The atomic coordinates and the cell parameters are optimized resulting in structures which agree with previous studies. The vibrational frequencies and modes are obtained for each mineral. The vibrational density of states is analyzed through extensive projections on silicon tetrahedra, oxygen atoms, OH groups, and water molecules. The coupling with the electric field is achieved through the use of density functional perturbation theory, which yields Born effective charges and dielectric constants. The simulated absorption spectra reproduce well the experimental spectra, thereby allowing for a detailed interpretation of the spectral features in terms of the underlying vibrational modes. In the far-infrared part of the absorption spectra, the interplay between Ca and Si related vibrations leads to differences which are sensitive to the calcium/silicon ratio of the mineral.

  18. High resolution infrared spectroscopy of [1.1.1]propellane: the region of the v9 band

    SciTech Connect

    Maki, Arthur; Weber, Alfons; Nibler, Joseph W.; Masiello, Tony; Blake, Thomas A.; Kirkpatrick, Robynne W.

    2010-11-01

    The region of the infrared-active ν9 CH2 bending band of [1.1.1] propellane has been recorded at resolution (0.0025 cm-1) sufficient to distinguish individual rovibrational lines. This region includes the partially overlapping bands ν9 (e′) = 1459 cm-1, 2ν18 (l = 2, E′) = 1430 cm-1, ν6 + ν12 (E′) = 1489 cm-1, and ν4 + ν15 (A2″) = 1518 cm-1. In addition, the difference band ν4 - ν15 (A2″) was observed in the far infrared near 295 cm-1 and analyzed to give good constants for the upper ν4 state. The close proximities of the four bands in the ν9 region suggest that Coriolis and Fermi resonance couplings could be significant and theoretical band parameters obtained from Gaussian ab initio calculations were helpful in guiding the band analyses. The analyses of all four bands were accomplished, based on our earlier report of ground state constants determined from combination differences involving more than 4000 pairs of transitions from five fundamental and four combination bands. This paper presents the analyses and the determination of the upper state constants of all four bands in the region of the ν9 band. Complications were most evident in the 2ν18 (l = 2, E′) band, which showed significant perturbations due to mixing with the nearby 2ν18 (l = 0, A1′) and ν6+ν12 (E') levels which are either infrared inactive as transitions from the ground state, or, in the latter case, too weak to observe. These complications are discussed and a comparison of all molecular constants with those available from the ab initio calculations at the anharmonic level is presented. 2

  19. Retrieving dust aerosols properties (optical depth and altitude) from very high resolution infrared sounders : from AIRS to IASI.

    NASA Astrophysics Data System (ADS)

    Peyridieu, S.; Chédin, A.; Capelle, V.; Pierangelo, C.; Lamquin, N.; Armante, R.

    2009-04-01

    Observation from space, being global and quasi-continuous, is a first importance tool for aerosol studies. Remote sensing in the visible domain has been widely used to obtain better characterization of these particles and their effect on solar radiation. On the opposite, remote sensing of aerosols in the thermal infrared domain still remains marginal. However, knowledge of the effect of aerosols on terrestrial radiation is needed for the evaluation of their total radiative forcing. Infrared remote sensing provides a way to retrieve other aerosol characteristics, including their mean altitude. Moreover, observations are possible at night and day, over ocean and over land. In this context, six years (2003-2008) of the 2nd generation vertical sounder AIRS observations have been processed over the tropical belt (30°N-30°S). Aerosol properties (10 µm infrared optical depth and mean layer altitude) are retrieved using a Look-Up Table (LUT) approach. The forward radiative transfer model 4A (Automatized Atmospheric Absorption Atlas) coupled with the DISORT algorithm accounting for atmospheric diffusion is used to feed the LUTs with simulations of the brightness temperatures of AIRS channels selected for their sensitivity to dust aerosols. LUTs degrees of freedom are : instrument viewing angle, surface pressure and surface emissivity, a parameter particularly important for dust retrieval over bright surfaces, such as deserts. AODs (resp. altitude) are sampled over the range 0.0-0.8 (resp. 0-5800 m). The retrieval algorithm follows two main steps : (i) retrieval of the atmospheric situation observed (temperature and water vapour profiles) ; (ii) retrieval of aerosol properties. Results have been compared to instruments commonly used in aerosol studies and also part of the Aqua Train : MODIS/Aqua and CALIOP/CALIPSO. The agreement obtained from these comparisons is quite satisfactory, demonstrating that our algorithm effectively allows the simultaneous retrieval of dust AOD

  20. Improving atmospheric CO2 retrievals using line mixing and speed-dependence when fitting high-resolution ground-based solar spectra

    NASA Astrophysics Data System (ADS)

    Mendonca, J.; Strong, K.; Toon, G. C.; Wunch, D.; Sung, K.; Deutscher, N. M.; Griffith, D. W. T.; Franklin, J. E.

    2016-05-01

    A quadratic speed-dependent Voigt spectral line shape with line mixing (qSDV + LM) has been included in atmospheric trace-gas retrievals to improve the accuracy of the calculated CO2 absorption coefficients. CO2 laboratory spectra were used to validate absorption coefficient calculations for three bands: the strong 20013 ← 00001 band centered at 4850 cm-1, and the weak 30013 ← 00001 and 30012 ← 00001 bands centered at 6220 cm-1 and 6340 cm-1 respectively, and referred to below as bands 1 and 2. Several different line lists were tested. Laboratory spectra were best reproduced for the strong CO2 band when using HITRAN 2008 spectroscopic data with air-broadened widths divided by 0.985, self-broadened widths divided by 0.978, line mixing coefficients calculated using the exponential power gap (EPG) law, and a speed-dependent parameter of 0.11 used for all lines. For the weak CO2 bands, laboratory spectra were best reproduced using spectroscopic parameters from the studies by Devi et al. in 2007 coupled with line mixing coefficients calculated using the EPG law. A total of 132,598 high-resolution ground-based solar absorption spectra were fitted using qSDV + LM to calculate CO2 absorption coefficients and compared to fits that used the Voigt line shape. For the strong CO2 band, the average root mean square (RMS) residual is 0.49 ± 0.22% when using qSDV + LM to calculate the absorption coefficients. This is an improvement over the results with the Voigt line shape, which had an average RMS residual of 0.60 ± 0.21%. When using the qSDV + LM to fit the two weak CO2 bands, the average RMS residual is 0.47 ± 0.19% and 0.51 ± 0.20% for bands 1 and 2, respectively. These values are identical to those obtained with the Voigt line shape. Finally, we find that using the qSDV + LM decreases the airmass dependence of the column averaged dry air mole fraction of CO2 retrieved from the strong and both weak CO2 bands when compared to the retrievals obtained using the Voigt

  1. High-resolution X-ray spectra of solar flares. VII - A long-duration X-ray flare associated with a coronal mass ejection

    NASA Technical Reports Server (NTRS)

    Kreplin, R. W.; Doschek, G. A.; Feldman, U.; Sheeley, N. R., Jr.; Seely, J. F.

    1985-01-01

    It has been recognized that very long duration X-ray events (lasting several hours) are frequently associated with coronal mass ejection. Thus, Sheeley et al. (1983) found that the probability of the occurrence of a coronal mass ejection (CME) increases monotonically with the X-ray event duration time. It is pointed out that the association of long-duration, or long-decay, X-ray events (LDEs) with CMEs was first recognized from analysis of solar images obtained by the X-ray telescopes on Skylab and the Naval Research Laboratory (NRL) slitless spectroheliograph. Recently high-resolution Bragg crystal X-ray spectrometers have been flown on three spacecraft, including the Department of Defense P78-1 spacecraft, the NASA Solar Maximum Mission (SMM), and the Japanese Hinotori spacecraft. In the present paper, P78-1 X-ray spectra of an LDE which had its origin behind the solar west limb on November 14, 1980 is presented. The obtained data make it possible to estimate temperatures of the hottest portion of the magnetic loops in which the emission arises.

  2. Application of high-resolution photoelectron spectroscopy: Vibrational resolved C 1s and O 1s spectra of CO adsorbed on Ni(100)

    SciTech Connect

    Foehlisch, A.; Nilsson, A.; Martensson, N.

    1997-04-01

    There are various effects which determine the line shape of a core-level electron spectrum. These are due to the finite life-time of the core hole, inelastic scattering of the outgoing photoelectron, electronic shake-up and shake-off processes and vibrational excitations. For free atoms and molecules the different contributions to the observed line shapes can often be well separated. For solids, surfaces and adsorbates the line shapes are in general much broader and it has in the past been assumed that no separation of the various contributions can be made. In the present report the authors will show that this is indeed not the case. Surprisingly, the vibrational fine structure of CO adsorbed on Ni(100) can be resolved in the C 1s and O 1s electron spectra. This was achieved by the combination of highly monochromatized soft X-rays from B18.0 with a high resolution Scienta 200 mm photoelectron spectrometer. X-ray photoelectron spectroscopy (XPS) with tunable excitation energy yields as a core level spectroscopy atomic and site-specific information. The presented measurements allow for a determination of internuclear distances and potential energy curves in corehole ionized adsorbed molecules. The authors analysis of the c(2x2) phase CO/Ni(100) on {open_quotes}top{close_quotes} yielded a vibrational splitting of 217 +/- 2 meV for C 1s ionization. For O 1s ionization a splitting of 173 +/- 8 meV was found.

  3. Tunneling Splittings in Vibronic Structure of CH_3F^+ ( X^2E): Studied by High Resolution Photoelectron Spectra and AB Initio Theoretical Method

    NASA Astrophysics Data System (ADS)

    Mo, Yuxiang; Gao, Shuming; Dai, Zuyang; Li, Hua

    2013-06-01

    We report a combined experimental and theoretical study on the vibronic structure of CH_3F^+. The results show that the tunneling splittings of vibrational energy levels occur in CH_3F^+ due to the Jahn-Teller effect. Experimentally, we have measured a high resolution ZEKE spectrum of CH_3F up to 3500 cm^-^1 above the ground state. Theoretically, we performed an ab initio calculation based on the diabatic model. The adiabatic potential energy surfaces (APES) of CH_3F^+ have been calculated at the MRCI/CAS/avq(t)z level and expressed by Taylor expansions with normal coordinates as variables. The energy gradients for the lower and upper APES, the derivative couplings between them and also the energies of the APES have been used to determine the coefficients in the Taylor expansion. The spin-vibronic energy levels have been calculated by accounting all six vibrational modes and their couplings. The experimental ZEKE spectra were assigned based on the theoretical calculations. W. Domcke, D. R. Yarkony, and H. Köpple (Eds.), Conical Intersections: Eletronic Structure, Dynamics and Spectroscopy (World Scientific, Singapore, 2004). M. S. Schuurman, D. E. Weinberg, and D. R. Yarkony, J. Chem. Phys. 127, 104309 (2007).

  4. Characteristics of the Fe II and C II emission in high-resolution IUE spectra (2300-3000 A) of Alpha Orionis

    NASA Technical Reports Server (NTRS)

    Carpenter, K. G.

    1984-01-01

    A study is presented of Fe II and C II emission features in the 2300-3000 A region of four high-resolution IUE spectra of Alpha Ori obtained during the period 1978 April-1982 November. A set of 42 unmutilated, unblended Fe II lines of multiplets UV 1-3, 32-33, 35-36, and 60-64 and the C II (UV 0.01) intercombination lines have been identified and measured to determine their velocities, fluxes, and asymmetries. A correlation of Fe II line asymmetry with intrinsic line strength indicates a velocity field which is initially constant, then algebraically increases with radius to a maximum value and then decreases significantly before reaching an asymptotic flow speed far from the star. The mean velocity of the chromospheric regions emitting Fe II does not appear to differ substantially from the time-average of the photospheric velocity, but there is evidence that the two regions are not strongly coupled and thus that the chromosphere does not strictly follow the semiperiodic 6 year pulsations of the photosphere. An analysis of the C II line fluxes produces estimates of the electron density in the chromosphere in the range 3.2 x 10 to the 7th-1.3 x 10 to the 8th per sq cm and indicates that the region emitting C II is geometrically thick, extending at least one-tenth, and perhaps as far as 1.2, photospheric radii from the base of the chromosphere.

  5. High-resolution infrared spectrum of jet-cooled methyl acetate in the C=O stretching region: internal rotations of two inequivalent methyl tops.

    PubMed

    Sunahori, Fumie X; Borho, Nicole; Liu, Xunchen; Xu, Yunjie

    2011-12-21

    The jet-cooled high resolution infrared (IR) spectrum of methyl acetate (MA), CH(3)-C(=O)-O-CH(3), in the C=O fundamental band region was recorded by using a rapid scan IR laser spectrometer equipped with an astigmatic multipass cell. No high resolution IR analyses of the ro-vibrational transitions between the ground and non-torsionally excited vibrational states have hitherto been reported for molecules with two inequivalent methyl rotors. Because of the two chemically different methyl tops in MA, i.e., the acetyl -CH(3) and methoxy -CH(3), each rotational energy level is split into more than two torsional sublevels by internal rotations of these methyl groups. We were able to assign ro-vibrational transitions of four torsional species by using the ground state combination differences calculated from the molecular constants of the vibrational ground state recently determined by a global fit of the microwave and millimeter wave lines [M. Tudorie, I. Kleiner, J. T. Hougen, S. Melandri, L. W. Sutikdja, and W. Stahl, J. Mol. Spectrosc. 269, 211 (2011)]. The assigned lines were successfully fitted using the BELGI-Cs-IR program to an overall standard deviation which is comparable to the measurement accuracy. This study is also of interest in understanding the role of methyl rotors in the intramolecular vibrational-energy redistribution processes in mid-size organic molecules. PMID:22191878

  6. High-resolution infrared spectrum of jet-cooled methyl acetate in the C=O stretching region: Internal rotations of two inequivalent methyl tops

    NASA Astrophysics Data System (ADS)

    Sunahori, Fumie X.; Borho, Nicole; Liu, Xunchen; Xu, Yunjie

    2011-12-01

    The jet-cooled high resolution infrared (IR) spectrum of methyl acetate (MA), CH3-C(=O)-O-CH3, in the C=O fundamental band region was recorded by using a rapid scan IR laser spectrometer equipped with an astigmatic multipass cell. No high resolution IR analyses of the ro-vibrational transitions between the ground and non-torsionally excited vibrational states have hitherto been reported for molecules with two inequivalent methyl rotors. Because of the two chemically different methyl tops in MA, i.e., the acetyl -CH3 and methoxy -CH3, each rotational energy level is split into more than two torsional sublevels by internal rotations of these methyl groups. We were able to assign ro-vibrational transitions of four torsional species by using the ground state combination differences calculated from the molecular constants of the vibrational ground state recently determined by a global fit of the microwave and millimeter wave lines [M. Tudorie, I. Kleiner, J. T. Hougen, S. Melandri, L. W. Sutikdja, and W. Stahl, J. Mol. Spectrosc. 269, 211 (2011)]. The assigned lines were successfully fitted using the BELGI-Cs-IR program to an overall standard deviation which is comparable to the measurement accuracy. This study is also of interest in understanding the role of methyl rotors in the intramolecular vibrational-energy redistribution processes in mid-size organic molecules.

  7. Infrared Extinction Spectra of Mineral Dust Aerosol

    NASA Astrophysics Data System (ADS)

    Kleiber, P.; Laskina, O.; Alexander, J. M.; Young, M.; Grassian, V. H.

    2012-12-01

    Mineral dust aerosol affects the atmosphere by absorbing and scattering radiation and plays an important role in the Earth's radiative budget. The effect of atmospheric dust on climate is studied by various remote sensing techniques that use measurements from narrow band IR channels of satellites to determine key atmospheric properties. Therefore, it is essential to take radiative effects of mineral dust aerosol into account to correctly process remote sensing data. As aerosols are transported through the atmosphere they undergo aging and heterogeneous chemistry. This leads to changes in their optical properties and their effects on climate. In this study we carried out spectral simulations using both Mie theory and solutions derived in the Rayleigh regime for authentic dust samples and several processed components of mineral dust. Simulations of the extinction based on Mie theory shows that it does not accurately reproduce the peak position and band shape of the prominent IR resonance features. Errors in the simulated peak position and the line shape associated with Mie theory can adversely affect determination of mineral composition based on IR satellite data. Analytic solutions for various shapes derived from Rayleigh theory offer a better fit to the major band features of the spectra, therefore the accuracy of modeling atmospheric dust properties can be improved by using these analytic solutions. It is also important to take aging of mineral dust into account. We investigated the effect of chemical processing on the optical properties. It was shown that interactions of components of mineral dust (calcite, quartz and kaolinite) with humic and organic acids cause a shift of the IR resonance bands of these minerals. It may indicate changes in shape of the particles as well as changes in hygroscopicity and, as the result, the water content in these samples. Therefore, care should be taken when modeling optical properties of aged mineral dust.

  8. HIRS-AMTS satellite sounding system test - Theoretical and empirical vertical resolving power. [High resolution Infrared Radiation Sounder - Advanced Moisture and Temperature Sounder

    NASA Technical Reports Server (NTRS)

    Thompson, O. E.

    1982-01-01

    The present investigation is concerned with the vertical resolving power of satellite-borne temperature sounding instruments. Information is presented on the capabilities of the High Resolution Infrared Radiation Sounder (HIRS) and a proposed sounding instrument called the Advanced Moisture and Temperature Sounder (AMTS). Two quite different methods for assessing the vertical resolving power of satellite sounders are discussed. The first is the theoretical method of Conrath (1972) which was patterned after the work of Backus and Gilbert (1968) The Backus-Gilbert-Conrath (BGC) approach includes a formalism for deriving a retrieval algorithm for optimizing the vertical resolving power. However, a retrieval algorithm constructed in the BGC optimal fashion is not necessarily optimal as far as actual temperature retrievals are concerned. Thus, an independent criterion for vertical resolving power is discussed. The criterion is based on actual retrievals of signal structure in the temperature field.

  9. Infrared spectra of interstellar deuteronated PAHs

    NASA Astrophysics Data System (ADS)

    Buragohain, Mridusmita; Pathak, Amit; Sarre, Peter

    2015-08-01

    Polycyclic Aromatic Hydrocarbon (PAH) molecules have emerged as a potential constituent of the ISM that emit strong features at 3.3, 6.2, 7.7, 8.6, 11.2 and 12.7 μm with weaker and blended features in the 3-20μm region. These features are proposed to arise from the vibrational relaxation of PAH molecules on absorption of background UV photons (Tielens 2008). These IR features have been observed towards almost all types of astronomical objects; say H II regions, photodissociation regions, reflection nebulae, planetary nebulae, young star forming regions, external galaxies, etc. A recent observation has proposed that interstellar PAHs are major reservoir for interstellar deuterium (D) (Peeters et al. 2004). According to the `deuterium depletion model' as suggested by Draine (2006), some of the Ds formed in the big bang are depleted in PAHs, which can account for the present value of D/H in the ISM. Hence, study of deuterated PAHs (PADs) is essential in order to measure D/H in the ISM.In this work, we consider another probable category of the large PAH family, i.e. Deuteronated PAHs (DPAH+). Onaka et al. have proposed a D/H ratio which is an order of magnitude smaller than the proposed value of D/H by Draine suggesting that if Ds are depleted in PAHs, they might be accommodated in large PAHs (Onaka et al. 2014). This work reports a `Density Functional Theory' calculation of large deuteronated PAHs (coronene, ovalene, circumcoronene and circumcircumcoronene) to determine the expected region of emission features and to find a D/H ratio that is comparable to the observational results. We present a detailed analysis of the IR spectra of these molecules and discuss the possible astrophysical implications.ReferencesDraine B. T. 2006, in ASP Conf. Ser. 348, Proc. Astrophysics in the Far Ultraviolet: Five Years of Discovery with FUSE, ed. G. Sonneborn, H. Moos, B-G Andersson (San Francisco, CA:ASP) 58Onaka T., Mori T. I., Sakon I., Ohsawa R., Kaneda H., Okada Y., Tanaka M

  10. Observation of infrared emission spectra from silicon combustion products

    NASA Astrophysics Data System (ADS)

    Smit, Kenneth J.; De Yong, Leo V.; Gray, Rodney

    1996-05-01

    The combustion of silicon based pyrotechnic compositions is observed with time resolved infrared spectrometry. This revealed the build up of strong emission at 9.1 ± 0.1 μm, which is associated with condensed silicon dioxide particulates. Time averaged spectra for compositions containing different oxidants or binders illustrate the dependence of SiO 2 emission intensity on composition.

  11. A Simulation Program for Dynamic Infrared (IR) Spectra

    ERIC Educational Resources Information Center

    Zoerb, Matthew C.; Harris, Charles B.

    2013-01-01

    A free program for the simulation of dynamic infrared (IR) spectra is presented. The program simulates the spectrum of two exchanging IR peaks based on simple input parameters. Larger systems can be simulated with minor modifications. The program is available as an executable program for PCs or can be run in MATLAB on any operating system. Source…

  12. FOURIER ENCODED DATA SEARCHING OF INFRARED SPECTRA (FEDS/IRS)

    EPA Science Inventory

    A new library searching technique is reported that relies on Fourier transforms of infrared (IR) absorbance spectra. Searching in the time domain is shown to be more tolerant to noise than searches in the spectral domain and fewer points are required to encode the unique characte...

  13. High resolution solar flare X-ray spectra - The temporal behavior of electron density, temperature, and emission measure for two class M flares

    NASA Astrophysics Data System (ADS)

    Doschek, G. A.; Feldman, U.; Landecker, P. B.; McKenzie, D. L.

    1981-10-01

    High resolution soft X-ray flare spectra recorded by Naval Research Laboratory (NRL) and Aerospace Corporation Bragg crystal spectrometers flown on an orbiting spacecraft (P78-1) are combined and analyzed. The instruments were launched on t979 February 24 by the U.S. Air Force, and the data discussed in this paper cover the wavelength ranges, 1.82-1.97 Å, 3.143.24 Å, and 18.423.0 Å. The NRL experiment (SOLFLEX) covers the two short wavelength ranges (highly ionized Fe and Ca lines) and the Aerospace experiment (SOLEX) covers the t8.4-23.O Å range, which includes the Lyα O VIII line and the resonance, intercombination, and forbidden lines of O VII. We analyze the spectra of two flares which occurred on 1980 April 8 and May 9. Temporal coverage is fairly complete for both flares, including the rise and decay phases. Measurements of electron density Ne with rather high time resolution (about 1 minute) have been obtained throughout most of the lifetimes of the two flares. These measurements were obtained from the O VII lines and pertain to flare plasma at temperatures near 2 × 106 K. Peak density seems to occur slightly before the times of peak X-ray flux in the resonance lines of Fe XXV, Ca XIX, and O VII, and for both flares the peak density is about 1012 cm-3. Electron temperature Te as a function of time is determined from the Fe and Ca spectra. Peak temperature for both flares is about 18 × 106 K. Differential emission measures and volume emission measures are determined from the resonance lines of O VII, Ca XIX, and Fe XXV. The number of electrons NeΔV and the volume ΔV over which the O VII lines are formed are determined from the O VII volume emission measure Ne2ΔV and the density Ne. These quantities are determined as a function of time. The relationship of the low and high temperature regions is discussed.

  14. W.M. Keck Telescope High Resolution Near-Infrared Imaging of FSC 10214+4724: Evidence for Gravitational Lensing

    NASA Astrophysics Data System (ADS)

    Liu, Michael C.; Graham, James R.

    1995-05-01

    We present near--infrared observations of the ultraluminous high--redshift (z=2.286) IRAS source FSC 10214+4724 obtained in 0.''4 seeing at the W. M. Keck Telescope. These new observations show that FSC 10214+4724 consists of a highly symmetric circular arc centered on a second weaker source. The arc has an angular extent of about 140(deg) and is probably unresolved in the transverse direction. This morphology constitutes compelling prima facie evidence for a gravitationally lensed system. Our images also contain evidence for the faint counter image predicted by the lens hypothesis. The morphology of FSC 10214+4724 can be explained in terms of a gravitationally lensed background source if the object located close to the center of the arc is an L(*) galaxy located at z~ 0.4 . The origin of the luminosity of FSC 10214+4724 is unclear -- it may be a protogalaxy undergoing its initial burst of star formation or a highly obscured quasar. If FSC 10214+4724 is lensed then there is significant magnification and its luminosity has been overestimated by a large factor. Our results suggest FSC 10214+4724 is not a uniquely luminous object but ranks among the most powerful quasars and ultraluminous IRAS galaxies.

  15. Analytic calculations of anharmonic infrared and Raman vibrational spectra.

    PubMed

    Cornaton, Yann; Ringholm, Magnus; Louant, Orian; Ruud, Kenneth

    2016-02-01

    Using a recently developed recursive scheme for the calculation of high-order geometric derivatives of frequency-dependent molecular properties [Ringholm et al., J. Comp. Chem., 2014, 35, 622], we present the first analytic calculations of anharmonic infrared (IR) and Raman spectra including anharmonicity both in the vibrational frequencies and in the IR and Raman intensities. In the case of anharmonic corrections to the Raman intensities, this involves the calculation of fifth-order energy derivatives-that is, the third-order geometric derivatives of the frequency-dependent polarizability. The approach is applicable to both Hartree-Fock and Kohn-Sham density functional theory. Using generalized vibrational perturbation theory to second order, we have calculated the anharmonic infrared and Raman spectra of the non- and partially deuterated isotopomers of nitromethane, where the inclusion of anharmonic effects introduces combination and overtone bands that are observed in the experimental spectra. For the major features of the spectra, the inclusion of anharmonicities in the calculation of the vibrational frequencies is more important than anharmonic effects in the calculated infrared and Raman intensities. Using methanimine as a trial system, we demonstrate that the analytic approach avoids errors in the calculated spectra that may arise if numerical differentiation schemes are used. PMID:26784673

  16. Far-infrared spectra of mesoporous ZnS nanoparticles

    NASA Astrophysics Data System (ADS)

    Trajić, J.; Romčević, M.; Romčević, N.; Babić, B.; Matović, B.; Baláž, P.

    2016-07-01

    ZnS nanoparticles were synthesized mechanochemically by high-energy milling, with three different milling times (5 min, 10 min and 20 min). Nitrogen adsorption method was used for examining specific surface area and texture of obtained powders. It was found that all samples are completely mesoporous. The optical properties were studied by far-infrared spectroscopy at room temperature in spectral region of 50-600 cm-1. The analysis of the far-infrared reflectivity spectra was made by the fitting procedure. The dielectric function of ZnS nanoparticles is modeled as a mixture of homogenous spherical inclusions in air by the Maxwell-Garnet formula. In the analysis of the far-infrared reflection spectra, appearance of combined plasmon-LO phonon modes (CPPMs) with high phonon damping are observed, which causes decrease of coupled plasmon-phonon frequencies.

  17. Visible/Near-Infrared Spectra of Experimentally Shocked Plagioclase Feldspars

    NASA Technical Reports Server (NTRS)

    Johnson, J. R.

    2003-01-01

    Minerals subjected to high shock pressures exhibit structural changes with increasing pressure (e.g., fractures, deformations, formation of diaplectic glass, and complete melting [1-6]). Petrologic and thermal infrared spectroscopic studies have shown that diaplectic glass (maskelynite) formation in feldspars occurs between 25-45 GPa, while significant melting occurs above 45 GPa [7- 12]. Past studies of visible/near-infrared spectra of shocked plagioclase feldspars demonstrated few variations in spectral features with pressure except for a decrease in the absorption feature near 1250 nm and an overall decrease in albedo [13-17]. We report new visible/near-infrared spectra of albite- and anorthiterich rocks experimentally shocked from 17-56 GPa.

  18. Infrared refractive index dispersion of polymethyl methacrylate spheres from Mie ripples in Fourier-transform infrared microscopy extinction spectra.

    PubMed

    Blümel, R; Bağcioğlu, M; Lukacs, R; Kohler, A

    2016-09-01

    We performed high-resolution Fourier-transform infrared (FTIR) spectroscopy of a polymethyl methacrylate (PMMA) sphere of unknown size in the Mie scattering region. Apart from a slow, oscillatory structure (wiggles), which is due to an interference effect, the measured FTIR extinction spectrum exhibits a ripple structure, which is due to electromagnetic resonances. We fully characterize the underlying electromagnetic mode structure of the spectrum by assigning mode numbers to each of the ripples in the measured spectrum. We show that analyzing the ripple structure in the spectrum in the wavenumber region from about 3000  cm-1 to 8000  cm-1 allows us to determine both the unknown radius of the sphere and the PMMA index of refraction, which shows a strong frequency dependence in this infrared spectral region. While in this paper we focus on examining a PMMA sphere as an example, our method of determining the refractive index and its dispersion from infrared extinction spectra is generally applicable for the determination of the index of refraction of any transparent substance that can be shaped into micron-sized spheres. PMID:27607489

  19. Close infrared thermography using an intensified CCD camera: application in nondestructive high resolution evaluation of electrothermally actuated MEMS

    NASA Astrophysics Data System (ADS)

    Serio, B.; Hunsinger, J. J.; Conseil, F.; Derderian, P.; Collard, D.; Buchaillot, L.; Ravat, M. F.

    2005-06-01

    This communication proposes the description of an optical method for thermal characterization of MEMS devices. The method is based on the use of an intensified CCD camera to record the thermal radiation emitted by the studied device in the spectral domain from 600 nm to about 850 nm. The camera consists of an intensifier associated to a CCD sensor. The intensification allows for very low signal levels to be amplified and detected. We used a standard optical microscope to image the device with sub-micron resolution. Since, in close infrared, at very small scale and low temperature, typically 250°C for thermal MEMS (Micro-Electro-Mechanical Systems), the thermal radiation is very weak, we used image integration in order to increase the signal to noise ratio. Knowing the imaged materials emissivity, the temperature is given by using Planck"s law. In order to evaluate the system performances we have made micro-thermographies of a micro-relay thermal actuator. This device is an "U-shape" Al/SiO2 bimorph cantilever micro-relay with a gold-to-gold electrical contact, designed for secured harsh environment applications. The initial beam curvature resulting from residual stresses ensures a large gap between the contacts of the micro-relay. The current flow through the metallic layer heats the bimorph by Joule effect, and the differential expansion provides the vertical displacement for contact. The experimental results are confronted to FEM and analytical simulations. A good agreement was obtained between experimental results and simulations.

  20. HIGH-RESOLUTION MID-INFRARED IMAGING OF THE CIRCUMSTELLAR DISKS OF HERBIG Ae/Be STARS

    SciTech Connect

    Marinas, N.; Telesco, C. M.; Packham, C.; Fisher, R. S.

    2011-08-20

    We have imaged the circumstellar environments of 17 Herbig Ae/Be stars at 12 and 18 {mu}m using MICHELLE on Gemini North and T-ReCS on Gemini South. Our sample contained eight Group I sources, those having large rising near- to far-infrared (IR) fluxes, and nine Group II sources, those having more modest mid-IR fluxes relative to their near-IR flux (in the classification of Meeus et al.). We have resolved extended emission from all Group I sources in our target list. The majority of these sources have radially symmetric mid-IR emission extending from a radius of 10 AU to hundreds of AU. Only one of the nine Group II sources is resolved at the FWHM level, with another two Group II sources resolved at fainter levels. Models by Dullemond et al. explain the observed spectral energy distribution of Group II sources using self-shadowed cold disks. If this is the case for all the Group II sources, we do not expect to detect extended emission with this study, since the IR emission measured should arise from a region only a few AU in size, which is smaller than our resolution. The fact that we do resolve some of the Group II sources implies that their disks are not completely flat, and might represent an intermediate stage. We also find that none of the more massive (>3 M{sub sun}) Herbig Ae/Be stars in our sample belongs to Group I, which may point to a relationship between stellar mass and circumstellar dust evolution. Disks around more massive stars might evolve faster so that stars are surrounded by a more evolved flat disk by the time they become optically visible, or they might follow a different evolutionary path altogether.

  1. Development of Fiber Fabry-Perot Interferometers as Stable Near-infrared Calibration Sources for High Resolution Spectrographs

    NASA Astrophysics Data System (ADS)

    Halverson, Samuel; Mahadevan, Suvrath; Ramsey, Lawrence; Hearty, Fred; Wilson, John; Holtzman, Jon; Redman, Stephen; Nave, Gillian; Nidever, David; Nelson, Matt; Venditti, Nick; Bizyaev, Dmitry; Fleming, Scott

    2014-05-01

    We discuss the ongoing development of single-mode fiber Fabry-Perot (FFP) Interferometers as precise astrophotonic calibration sources for high precision radial velocity (RV) spectrographs. FFPs are simple, inexpensive, monolithic units that can yield a stable and repeatable output spectrum. An FFP is a unique alternative to a traditional etalon, as the interferometric cavity is made of single-mode fiber rather than an air-gap spacer. This design allows for excellent collimation, high spectral finesse, rigid mechanical stability, insensitivity to vibrations, and no need for vacuum operation. The device we have tested is a commercially available product from Micron Optics.10 Our development path is targeted toward a calibration source for the Habitable-Zone Planet Finder (HPF), a near-infrared spectrograph designed to detect terrestrial-mass planets around low-mass stars, but this reference could also be used in many existing and planned fiber-fed spectrographs as we illustrate using the Apache Point Observatory Galactic Evolution Experiment (APOGEE) instrument. With precise temperature control of the fiber etalon, we achieve a thermal stability of 100 μK and associated velocity uncertainty of 22 cm s-1. We achieve a precision of ≈2 m s-1 in a single APOGEE fiber over 12 hr using this new photonic reference after removal of systematic correlations. This high precision (close to the expected photon-limited floor) is a testament to both the excellent intrinsic wavelength stability of the fiber interferometer and the stability of the APOGEE instrument design. Overall instrument velocity precision is 80 cm s-1 over 12 hr when averaged over all 300 APOGEE fibers and after removal of known trends and pressure correlations, implying the fiber etalon is intrinsically stable to significantly higher precision.

  2. High-resolution synchrotron infrared spectroscopy of thiophosgene: The ν1, ν5, 2ν4, and ν2 + 2ν6 bands

    NASA Astrophysics Data System (ADS)

    McKellar, A. R. W.; Billinghurst, B. E.

    2015-09-01

    Thiophosgene (Cl2CS) is a favorite model system for studies of photophysics, vibrational dynamics, and intersystem interactions. But its infrared spectra tend to be very congested due to hot bands and multiple isotopic species. This paper reports the first detailed study of the ν1 (∼1139 cm-1) and ν5 (∼820 cm-1) fundamental bands for the two most abundant isotopologues, 35Cl2CS and 35Cl37ClCS, based on spectra with a resolution of about 0.001 cm-1 obtained at the Canadian Light Source far-infrared beamline using synchrotron radiation and a Bruker IFS125 Fourier transform spectrometer. The 2ν4 (∼942 cm-1) and ν2 + 2ν6 (∼1104 cm-1) bands are also studied here, but the ν2 + ν6 band (∼795 cm-1) resisted full analysis.

  3. TESTING THE HYPOTHESIS THAT METHANOL MASER RINGS TRACE CIRCUMSTELLAR DISKS: HIGH-RESOLUTION NEAR-INFRARED AND MID-INFRARED IMAGING

    SciTech Connect

    De Buizer, James M.; Bartkiewicz, Anna; Szymczak, Marian

    2012-08-01

    Milliarcsecond very long baseline interferometry maps of regions containing 6.7 GHz methanol maser emission have lead to the recent discovery of ring-like distributions of maser spots and the plausible hypothesis that they may be tracing circumstellar disks around forming high-mass stars. We aimed to test this hypothesis by imaging these regions in the near- and mid-infrared at high spatial resolution and compare the observed emission to the expected infrared morphologies as inferred from the geometries of the maser rings. In the near-infrared we used the Gemini North adaptive optics system of ALTAIR/NIRI, while in the mid-infrared we used the combination of the Gemini South instrument T-ReCS and super-resolution techniques. Resultant images had a resolution of {approx}150 mas in both the near-infrared and mid-infrared. We discuss the expected distribution of circumstellar material around young and massive accreting (proto)stars and what infrared emission geometries would be expected for the different maser ring orientations under the assumption that the masers are coming from within circumstellar disks. Based upon the observed infrared emission geometries for the four targets in our sample and the results of spectral energy distribution modeling of the massive young stellar objects associated with the maser rings, we do not find compelling evidence in support of the hypothesis that methanol masers rings reside in circumstellar disks.

  4. High-resolution Mid-infrared Imaging of the Circumstellar Disks of Herbig Ae/Be Stars

    NASA Astrophysics Data System (ADS)

    Mariñas, N.; Telesco, C. M.; Fisher, R. S.; Packham, C.

    2011-08-01

    We have imaged the circumstellar environments of 17 Herbig Ae/Be stars at 12 and 18 μm using MICHELLE on Gemini North and T-ReCS on Gemini South. Our sample contained eight Group I sources, those having large rising near- to far-infrared (IR) fluxes, and nine Group II sources, those having more modest mid-IR fluxes relative to their near-IR flux (in the classification of Meeus et al.). We have resolved extended emission from all Group I sources in our target list. The majority of these sources have radially symmetric mid-IR emission extending from a radius of 10 AU to hundreds of AU. Only one of the nine Group II sources is resolved at the FWHM level, with another two Group II sources resolved at fainter levels. Models by Dullemond et al. explain the observed spectral energy distribution of Group II sources using self-shadowed cold disks. If this is the case for all the Group II sources, we do not expect to detect extended emission with this study, since the IR emission measured should arise from a region only a few AU in size, which is smaller than our resolution. The fact that we do resolve some of the Group II sources implies that their disks are not completely flat, and might represent an intermediate stage. We also find that none of the more massive (>3 M sun) Herbig Ae/Be stars in our sample belongs to Group I, which may point to a relationship between stellar mass and circumstellar dust evolution. Disks around more massive stars might evolve faster so that stars are surrounded by a more evolved flat disk by the time they become optically visible, or they might follow a different evolutionary path altogether. 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 NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National

  5. Survey of the high resolution infrared spectrum of methane ({sup 12}CH{sub 4} and {sup 13}CH{sub 4}): Partial vibrational assignment extended towards 12 000 cm{sup −1}

    SciTech Connect

    Ulenikov, O. N.; Bekhtereva, E. S.; Albert, S.; Bauerecker, S.; Niederer, H. M.; Quack, M.

    2014-12-21

    We have recorded the complete infrared spectrum of methane {sup 12}CH{sub 4} and its second most abundant isotopomer {sup 13}CH{sub 4} extending from the fundamental range starting at 1000 cm{sup −1} up to the overtone region near 12 000 cm{sup −1} in the near infrared at the limit towards the visible range, at temperatures of about 80 K and also at 298 K with Doppler limited resolution in the gas phase by means of interferometric Fourier transform spectroscopy using the Bruker IFS 125 HR prototype (ZP 2001) of the ETH Zürich laboratory. This provides the so far most complete data set on methane spectra in this range at high resolution. In the present work we report in particular those results, where the partial rovibrational analysis allows for the direct assignment of pure (J = 0) vibrational levels including high excitation. These results substantially extend the accurate knowledge of vibrational band centers to higher energies and provide a benchmark for both the comparison with theoretical results on the one hand and atmospheric spectroscopy on the other hand. We also present a simple effective Hamiltonian analysis, which is discussed in terms of vibrational level assignments and {sup 13}C isotope effects.

  6. Multivariate calibration applied to the quantitative analysis of infrared spectra

    NASA Astrophysics Data System (ADS)

    Haaland, David M.

    1992-03-01

    Multivariate calibration methods are very useful for improving the precision, accuracy, and reliability of quantitative spectral analyses. Spectroscopists can more effectively use these sophisticated statistical tools if they have a qualitative understanding of the techniques involved. A qualitative picture of the factor analysis multivariate calibration methods of partial least squares (PLS) and principal component regression (PCR) is presented using infrared calibrations based upon spectra of phosphosilicate glass thin films on silicon wafers. Comparisons of the relative prediction abilities of four different multivariate calibration methods are given based on Monte Carlo simulations of spectral calibration and prediction data. The success of multivariate spectral calibrations is demonstrated for several quantitative infrared studies. The infrared absorption and emission spectra of thin-film dielectrics used in the manufacture of microelectronic devices demonstrate rapid, nondestructive at-line and in- situ analyses using PLS calibrations. Finally, the application of multivariate spectral calibrations to reagentless analysis of blood is presented. We have found that the determination of glucose in whole blood taken from diabetics can be precisely monitored from the PLS calibration of either mid- or near-infrared spectra of the blood. Progress toward the noninvasive determination of glucose levels in diabetics is an ultimate goal of this research.

  7. Multivariate calibration applied to the quantitative analysis of infrared spectra

    SciTech Connect

    Haaland, D.M.

    1991-01-01

    Multivariate calibration methods are very useful for improving the precision, accuracy, and reliability of quantitative spectral analyses. Spectroscopists can more effectively use these sophisticated statistical tools if they have a qualitative understanding of the techniques involved. A qualitative picture of the factor analysis multivariate calibration methods of partial least squares (PLS) and principal component regression (PCR) is presented using infrared calibrations based upon spectra of phosphosilicate glass thin films on silicon wafers. Comparisons of the relative prediction abilities of four different multivariate calibration methods are given based on Monte Carlo simulations of spectral calibration and prediction data. The success of multivariate spectral calibrations is demonstrated for several quantitative infrared studies. The infrared absorption and emission spectra of thin-film dielectrics used in the manufacture of microelectronic devices demonstrate rapid, nondestructive at-line and in-situ analyses using PLS calibrations. Finally, the application of multivariate spectral calibrations to reagentless analysis of blood is presented. We have found that the determination of glucose in whole blood taken from diabetics can be precisely monitored from the PLS calibration of either mind- or near-infrared spectra of the blood. Progress toward the non-invasive determination of glucose levels in diabetics is an ultimate goal of this research. 13 refs., 4 figs.

  8. Contradictions about Fine Structures in Meson Spectra and Proposed High-Resolution Hadron Spectrometer Using ``Interactive'' Solid-State Hydrogen Target

    NASA Astrophysics Data System (ADS)

    Maglich, Bogdan C.

    2004-08-01

    High resolution has been discouraged in meson spectrometry for 4 decades by the Doctrine of Experiments Incompatible with Theory (DEIT). DEIT a priori rejects narrow hadron resonances on the paradigm that only broad hadron peaks, Γ⩾ 100 MeV, can exist — in spite of the accumulated evidence to the contrary. The facts are: Mesons 2 orders of magnitude narrower than `allowed' for hadrons, have been confirmed; a new one was announced at this conference. Narrow meson structures have been repeatedly reported at high momentum transfer, |t| >0.2, while they are absent at the low transfer, |t| ˜0.01, where 99% of the experiments are performed. Modification of meson mass and width as a function of the density of nuclear matter in which they are produced, have been recently reported. We postulate for meson spectra: (1) Intrinsic (`true') width, Γ, is different from the observable (`apparent') width, Γ': Γ< Γ' (2) Γ of all meson states are narrow and can be observed only at or near the maximum |t| reachable in the reaction, and (3) Γ of all meson resonances are subject to broadening as |t| decreases. Since both Γ' and the production σ are inversely proportional to |t|, most of the observed spectra are produced at the lowest |t| <0.01 and thus the peaks appear broad. We have conceptually designed a novel type hadron spectrometer with an order of magnitude better resolution (0.1 MeV). It would operate at 2 orders of magnitude higher |t| (0.3< |t| <1 (GeV/c)2, than most experiments to date (|t| <0.01). Mesons in the mass region 0.5

  9. Non-destructive testing for combined stresses using high-resolution thermal infrared remote sensing and ''three-temperature model'': A case study on mangrove plant Kandelia obovata

    NASA Astrophysics Data System (ADS)

    Shen, X.; LI, R.; Li, Y. H.; Chai, M. W.; Qiu, G. Y.

    2015-12-01

    Mangrove forests are currently facing serious heavy metal pollution and eutrophication problems. Remote sensing of vegetation is a non-invasive methodology to monitor physiological characteristics of plants. The potential of high-resolution thermal infrared remote sensing and the three-temperature model (3T model) for monitoring the effects of combined stresses on mangrove plant Kandelia obovata was assessed. The experiment consists of four levels of CdCl2 stress (0, 1, 5 and 10 mg·L-1) in each of four NH4Cl stress levels: 0, 10, 50 and 100 mg·L-1, respectively. The non-destructive testing indices, including plant transpiration transfer coefficient (hat) and estimated instant transpiration rate, were calculated from thermal images and the 3T model. The photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) were also tested to validate the results of non-destructive testing. The results showed that: (1) The plant transpiration transfer coefficients (hat) were changed from 0.246 to 0.928 and the estimated instant transpiration rates ranged from 0.590 to 6.119 mmol H2O m-2s-1 among different combined stresses. With increasing stress, there were significant decreases for estimated instant transpiration rate and increases for hat (P < 0.05). (2) The photosynthetic characteristics, including Pn, Gs and Tr, were significantly decreased with the increasing combined stresses (P < 0.05). (3) The effects of Cd, N, and their interaction on non-destructive indices and photosynthetic parameters were significant (P < 0.05). (4) The hat was significantly negatively correlated with photosynthetic parameters and the T-3T was significantly positively correlated with photosynthetic parameters (P < 0.05). Therefore, the transpiration transfer coefficient (hat) andestimated instant transpiration rate detecting by infrared thermography device could be indicators to reflect the stress conditions. Based on high-resolution thermal infrared remote sensing, we

  10. Infrared transmission spectra of Sea of Fertility regolith

    NASA Technical Reports Server (NTRS)

    Akhmanova, M. V.; Karyakin, A. V.; Tartasov, L. S.

    1974-01-01

    Transmission spectra in the 2-25 micrometer region were obtained for samples of lunar regolith returned by the Luna 16 automatic station. A comparison of the Luna 16, Apollo 11, and Apollo 12 samples showed that the infrared transmission spectra of regolith samples from the mare regions are similar and characteristic of basic basaltic rocks. The absorption bands show up in the vibration region of the SiO4 groups. No water and OH groups were found in the samples based on the spectrum. Spectra of regolith samples calcined at 1000C showed changes that can be interpreted as changes in the spectra of irradiated crystals (especially distinctly for the Luna 16 samples).

  11. INFRARED SPECTRA OF ISOLATED PROTONATED POLYCYCLIC AROMATIC HYDROCARBON MOLECULES

    SciTech Connect

    Knorke, Harald; Langer, Judith; Dopfer, Otto; Oomens, Jos

    2009-11-20

    Gas-phase infrared (IR) spectra of larger protonated polycyclic aromatic hydrocarbon molecules, H{sup +}PAH, have been recorded for the first time. The ions are generated by electrospray ionization and spectroscopically assayed by IR multiple-photon dissociation (IRMPD) spectroscopy in a Fourier transform ion cyclotron resonance mass spectrometer using a free electron laser. IRMPD spectra of protonated anthracene, tetracene, pentacene, and coronene are presented and compared to calculated IR spectra. Comparison of the laboratory IR spectra to an astronomical spectrum of the unidentified IR emission (UIR) bands obtained in a highly ionized region of the interstellar medium provides for the first time compelling spectroscopic support for the recent hypothesis that H{sup +}PAHs contribute as carriers of the UIR bands.

  12. Far-infrared reflectance spectra of optical black coatings

    NASA Technical Reports Server (NTRS)

    Smith, S. M.

    1983-01-01

    Far-infrared specular reflectance spectra of six optically black coatings near normal incidence are presented. The spectra were obtained using nine bandpass transmission filters in the wavelength range between 12 and 300 microns. Data on the construction, thickness, and rms surface roughness of the coatings are also presented. The chemical composition of two coatings can be distinguished from that of the others by a strong absorption feature between 20 and 40 microns which is attributed to amorphous silicate material. Inverse relationships between these spectra and coating roughness and thickness are noted and lead to development of a reflecting-layer model for the measured reflectance. The model is applied to the spectra of several coatings whose construction falls within its constraints.

  13. Infrared spectra of olivine polymorphs - Alpha, beta phase and spinel

    NASA Technical Reports Server (NTRS)

    Jeanloz, R.

    1980-01-01

    The infrared absorption spectra of several olivines (alpha phase) and their corresponding beta phase (modified spinel) and spinel (gamma) high-pressure polymorphs are determined. Spectra were measured for ground and pressed samples of alpha and gamma A2SiO4, where A = Fe, Ni, Co; alpha and gamma Mg2GeO4; alpha Mg2SiO4; and beta Co2SiO4. The spectra are interpreted in terms of internal, tetrahedral and octagonal, and lattice vibration modes, and the spinel results are used to predict the spectrum of gamma Mg2SiO4. Analysis of spectra obtained from samples of gamma Mg2GeO4 heated to 730 and 1000 C provides evidence that partial inversion could occur in silicate spinels at elevated temperatures and pressures.

  14. First Infrared Predissociation Spectra of He-TAGGED Protonated Primary Alcohols at 4 K

    NASA Astrophysics Data System (ADS)

    Stoffels, Alexander; Redlich, Britta; Oomens, J.; Asvany, Oskar; Brünken, Sandra; Jusko, Pavol; Thorwirth, Sven; Schlemmer, Stephan

    2015-06-01

    Cryogenic multipole ion traps have become popular devices in the development of sensitive action-spectroscopic techniques. The low ion temperature leads to enhanced spectral resolution, and less congested spectra. In the early 2000s, a 22-pole ion trap was coupled to the Free-Electron Laser for Infrared eXperiments (FELIX), yielding infrared Laser Induced Reaction (LIR) spectra of the molecular ions C_2H_2+ and CH_5+. This pioneering work showed the great opportunities combining cold mass-selected molecular ions with widely tunable broadband IR radiation. In the past year a cryogenic (T>3.9 K) 22-pole ion trap designed and built in Cologne (FELion) has been successfully coupled to FELIX, which in its current configuration provides continuously tunable infrared radiation from 3 μm to 150 μm, hence allowing to probe characteristic vibrational spectra in the so-called "fingerprint region" with a sufficient spectral energy density also allowing for multiple photon processes (IR-MPD). Here we present the first infrared predissociation spectra of He-tagged protonated methanol and ethanol (MeOH_2+/EtOH_2+) stored at 4 K. These vibrational spectra were recorded with both a commercial OPO and FELIX, covering a total spectral range from 3700 wn to 550 wn at a spectral resolution of a few wn. The H-O-H stretching and bending modes clearly distinguish the protonated alcohols from their neutral analoga. For EtOH_2+, also IR-MPD spectra of the bare ion could be recorded. The symmetric and antisymmetric H-O-H stretching bands at around 3 μm show no significant shift within the given spectral resolution in comparison to those recorded with He predissociation, indicating a rather small perturbation caused by the attached He. The vibrational bands were assigned using quantum-chemical calculations on different levels of theory. The computed frequencies correspond favorably to the experimental spectra. Subsequent high resolution measurements could lead to a better structural

  15. High Resolution Spectra and Rotational Analysis of the 2ν 8, ν 2+ ν 8, and 2ν 2Bands in Methylene Chloride

    NASA Astrophysics Data System (ADS)

    Snels, Marcel

    1997-03-01

    The infrared spectra of the 2ν8, ν2+ ν8, and 2ν2bands of methylene chloride have been recorded both for isotopically pure CH235Cl2and for a natural mixture with a resolution of 0.0044 cm-1in the range 2450-2900 cm-1using a Bruker IFS 120 HR Fourier transform interferometer. The 2ν8overtone band was shown to be unperturbed. Weak global perturbations were observed, however, in the ν2+ ν8combination band, probably due to Fermi or Coriolis interaction with a distant perturber. The 2ν2overtone was found to be locally perturbed, and a crossing aroundK‧a= 10 with a perturbing level was evident from a line-by-line analysis. A satisfactory analysis of 2ν2has been obtained by including anx-Coriolis interaction with a vibrational level ofA2symmetry, presumably the ν2+ ν4+ ν5combination band. A full rotational analysis for all bands has been carried out, yielding accurate effective rotational and distortion constants up to quartic terms for the excited states using Watson'sA-reduction Hamiltonian in theIrrepresentation. In addition a hot-band starting from the lowest lying vibrational level, ν4, the 2ν8+ ν4- ν4band, has been partially analyzed. Vibrational shifts of the CH372Cl35Cl isotopic species have been obtained from difference spectra (i.e., spectra of natural abundant CH2Cl2minus those of isotopically pure CH352Cl2). In particular a full rotational analysis of the 2ν8band of the CH372Cl35Cl isotopomer has been performed. Unfortunately, the spectral features due to the CH372Cl2isotopomer were too weak (about 6 times weaker than those of CH372Cl35Cl) to be observed.

  16. MISTiC Winds, a Micro-Satellite Constellation Approach to High Resolution Observations of the Atmosphere using Infrared Sounding and 3D Winds Measurements

    NASA Astrophysics Data System (ADS)

    Maschhoff, K. R.; Polizotti, J. J.; Susskind, J.; Aumann, H. H.

    2015-12-01

    MISTiCTM Winds is an approach to improve short-term weather forecasting based on a miniature high resolution, wide field, thermal emission spectrometry instrument that will provide global tropospheric vertical profiles of atmospheric temperature and humidity at high (3-4 km) horizontal and vertical ( 1 km) spatial resolution. MISTiC's extraordinarily small size, payload mass of less than 15 kg, and minimal cooling requirements can be accommodated aboard a 27U-class CubeSat or an ESPA-Class micro-satellite. Low fabrication and launch costs enable a LEO sun-synchronous sounding constellation that would collectively provide frequent IR vertical profiles and vertically resolved atmospheric motion vector wind observations in the troposphere. These observations are highly complementary to present and emerging environmental observing systems, and would provide a combination of high vertical and horizontal resolution not provided by any other environmental observing system currently in operation. The spectral measurements that would be provided by MISTiC Winds are similar to those of NASA's Atmospheric Infrared Sounder that was built by BAE Systems and operates aboard the AQUA satellite. These new observations, when assimilated into high resolution numerical weather models, would revolutionize short-term and severe weather forecasting, save lives, and support key economic decisions in the energy, air transport, and agriculture arenas-at much lower cost than providing these observations from geostationary orbit. In addition, this observation capability would be a critical tool for the study of transport processes for water vapor, clouds, pollution, and aerosols. Key technical risks are being reduced through laboratory and airborne testing under NASA's Instrument Incubator Program.

  17. Very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    Aronson, A. I.

    1974-01-01

    A primary sensor used in environmental and earth-resource observation, the Very High Resolution Radiometer (VHRR) was designed for use on the ITOS D series spacecraft. The VHRR provides a 0.47 mile resolution made possible with a mercury-cadmium-telluride detector cooled to approximately 105 K by a passive radiator cooler. The components of this system are described. The optical subsystem of the VHRR consists of a scanning mirror, a Dall-Kirkham telescope, a dichroic beam splitter, relay lenses, spectral filters, and an IR detector. Signal electronics amplify and condition the signals from the infrared and visible light detector. Sync generator electronics provides the necessary time signals. Scan-drive electronics is used for commutation of the motor winding, velocity, and phase control. A table lists the performance parameters of the VHRR.

  18. Infrared absorption spectra of metal carbides, nitrides and sulfides

    NASA Technical Reports Server (NTRS)

    Kammori, O.; Sato, K.; Kurosawa, F.

    1981-01-01

    The infrared absorption spectra of 12 kinds of metal carbides, 11 kinds of nitrides, and 7 kinds of sulfides, a total of 30 materials, were measured and the application of the infrared spectra of these materials to analytical chemistry was discussed. The measurements were done in the frequency (wave length) range of (1400 to 400/cm (7 to 25 mu). The carbides Al4C3, B4C, the nitrides AlN, BN, Si3N4, WB, and the sulfides Al2S3, FeS2, MnS, NiS and PbS were noted to have specific absorptions in the measured region. The sensitivity of Boron nitride was especially good and could be detected at 2 to 3 micrograms in 300 mg of potassium bromide.

  19. Nondestructive evaluation of aircraft coatings with infrared diffuse reflectance spectra

    NASA Astrophysics Data System (ADS)

    Korth, Hans G.; Wilson, Kody A.; Gross, Kevin C.; Hawks, Michael R.; Zens, Timothy W. C.

    2015-05-01

    Aircraft coatings degrade over time, but aging can be difficult to detect before failure and delamination. We present a method to evaluate aircraft coatings in situ using infrared diffuse reflectance spectra. This method can detect and classify coating degradation much earlier than visual inspection. The method has been tested on two different types of coatings that were artificially aged in an autoclave. Spectra were measured using a hand-held diffuse reflectance infrared Fourier transform spectrometer (DRIFTS). One set of 72 samples can be classified as either aged or unaged with 100% accuracy. A second sample set contained samples that had been artificially aged for 0, 24, 48 or 96 hours. Several classification methods are compared, with accuracy better than 98% possible.

  20. Suomi NPP/JPSS Cross-track Infrared Sounder (CrIS): Calibration Validation With The Aircraft Based Scanning High-resolution Interferometer Sounder (S-HIS)

    NASA Astrophysics Data System (ADS)

    Taylor, J. K.; Revercomb, H. E.; Tobin, D.; Knuteson, R. O.; Best, F. A.; Adler, D. A.; Pettersen, C.; Garcia, R. K.; Gero, P.

    2013-12-01

    To better accommodate climate change monitoring and improved weather forecasting, there is an established need for higher accuracy and more refined error characterization of radiance measurements from space and the corresponding geophysical products. This need has led to emphasizing direct tests of on-orbit performance, referred to as validation. Currently, validation typically involves (1) collecting high quality reference data from airborne and/or ground-based instruments during the satellite overpass, and (2) a detailed comparison between the satellite-based radiance measurements and the corresponding high quality reference data. Additionally, for future missions technology advancements at the University of Wisconsin Space Science and Engineering Center (UW-SSEC) have led to the development of an on-orbit absolute radiance reference utilizing miniature phase change cells to provide direct on-orbit traceability to International Standards (SI). The detailed comparison between the satellite-based radiance measurements and the corresponding measurements made from a high-altitude aircraft must account for instrument noise and scene variations, as well as differences in instrument observation altitudes, view angles, spatial footprints, and spectral response. Most importantly, for the calibration validation process to be both accurate and repeatable the reference data instrument must be extremely well characterized and understood, carefully maintained, and accurately calibrated, with traceability to absolute standards. The Scanning High-resolution Interferometer Sounder (S-HIS) meets and exceeds these requirements and has proven to do so on multiple airborne platforms, each with significantly different instrument operating environments. The Cross-track Infrared Sounder (CrIS) on Suomi NPP, launched 28 October 2011, is designed to give scientists more refined information about Earth's atmosphere and improve weather forecasts and our understanding of climate. CrIS is an

  1. Visible/near-infrared spectra of experimentally shocked plagioclase feldspars

    USGS Publications Warehouse

    Johnson, J. R.; Horz, F.

    2003-01-01

    High shock pressures cause structural changes in plagioclase feldspars such as mechanical fracturing and disaggregation of the crystal lattice at submicron scales, the formation of diaplectic glass (maskelynite), and genuine melting. Past studies of visible/ near-infrared spectra of shocked feldspars demonstrated few spectral variations with pressure except for a decrease in the depth of the absorption feature near 1250-1300 nm and an overall decrease in reflectance. New visible/near-infrared spectra (400-2500 nm) of experimentally shocked (17-56 GPa) albite- and anorthite-rich rock powders demonstrate similar trends, including the loss of minor hydrated mineral bands near 1410, 1930, 2250, and 2350 nm. However, the most interesting new observations are increases in reflectance at intermediate pressures, followed by subsequent decreases in reflectance at higher pressures. The amount of internal scattering and overall sample reflectance is controlled by the relative proportions of micro-fractures, submicron grains, diaplectic glass, and melts formed during shock metamorphism. We interpret the observed reflectance increases at intermediate pressures to result from progressively larger proportions of submicron feldspar grains and diaplectic glass. The ensuing decreases in reflectance occur after diaplectic glass formation is complete and the proportion of genuine melt inclusions increases. The pressure regimes over which these reflectance variations occur differ between albite and anorthite, consistent with thermal infrared spectra of these samples and previous studies of shocked feldspars. These types of spectral variations associated with different peak shock pressures should be considered during interpretation and modeling of visible/near-infrared remotely sensed spectra of planetary and asteroidal surfaces.

  2. Infrared spectra of CO adsorbed at low temperatures on Ni

    SciTech Connect

    Levinson, H.J.; Tobin, R.G.; Richards, P.L.

    1982-09-01

    At low temperatures (1.5 to 40/sup 0/K), CO has been found to chemisorb into terminal, bridge, and three-fold sites on evaporated Ni films. The chemisorption takes place directly, rather than through a precursor state. At least two distinct terminal sites are occupied at high coverages. After the sample is warmed from 1.5 to 40/sup 0/K the infrared spectra change dramatically, showing substantial surface diffusion even at these low temperatures. 4 figures.

  3. Visible/near-infrared spectra of experimentally shocked plagioclase feldspars

    NASA Astrophysics Data System (ADS)

    Johnson, Jeffrey R.; Hörz, Friedrich

    2003-11-01

    High shock pressures cause structural changes in plagioclase feldspars such as mechanical fracturing and disaggregation of the crystal lattice at submicron scales, the formation of diaplectic glass (maskelynite), and genuine melting. Past studies of visible/near-infrared spectra of shocked feldspars demonstrated few spectral variations with pressure except for a decrease in the depth of the absorption feature near 1250-1300 nm and an overall decrease in reflectance. New visible/near-infrared spectra (400-2500 nm) of experimentally shocked (17-56 GPa) albite- and anorthite-rich rock powders demonstrate similar trends, including the loss of minor hydrated mineral bands near 1410, 1930, 2250, and 2350 nm. However, the most interesting new observations are increases in reflectance at intermediate pressures, followed by subsequent decreases in reflectance at higher pressures. The amount of internal scattering and overall sample reflectance is controlled by the relative proportions of micro-fractures, submicron grains, diaplectic glass, and melts formed during shock metamorphism. We interpret the observed reflectance increases at intermediate pressures to result from progressively larger proportions of submicron feldspar grains and diaplectic glass. The ensuing decreases in reflectance occur after diaplectic glass formation is complete and the proportion of genuine melt inclusions increases. The pressure regimes over which these reflectance variations occur differ between albite and anorthite, consistent with thermal infrared spectra of these samples and previous studies of shocked feldspars. These types of spectral variations associated with different peak shock pressures should be considered during interpretation and modeling of visible/near-infrared remotely sensed spectra of planetary and asteroidal surfaces.

  4. Infrared absorption spectra of human malignant tumor tissues

    NASA Astrophysics Data System (ADS)

    Skornyakov, I. V.; Tolstorozhev, G. B.; Butra, V. A.

    2008-05-01

    We used infrared spectroscopy methods to study the molecular structure of tissues from human organs removed during surgery. The IR spectra of the surgical material from breast, thyroid, and lung are compared with data from histological examination. We show that in malignant neoplasms, a change occurs in the hydrogen bonds of protein macromolecules found in the tissue of the studied organs. We identify the spectral signs of malignant pathology.

  5. Automatic classification of spectra from the Infrared Astronomical Satellite (IRAS)

    NASA Technical Reports Server (NTRS)

    Cheeseman, Peter; Stutz, John; Self, Matthew; Taylor, William; Goebel, John; Volk, Kevin; Walker, Helen

    1989-01-01

    A new classification of Infrared spectra collected by the Infrared Astronomical Satellite (IRAS) is presented. The spectral classes were discovered automatically by a program called Auto Class 2. This program is a method for discovering (inducing) classes from a data base, utilizing a Bayesian probability approach. These classes can be used to give insight into the patterns that occur in the particular domain, in this case, infrared astronomical spectroscopy. The classified spectra are the entire Low Resolution Spectra (LRS) Atlas of 5,425 sources. There are seventy-seven classes in this classification and these in turn were meta-classified to produce nine meta-classes. The classification is presented as spectral plots, IRAS color-color plots, galactic distribution plots and class commentaries. Cross-reference tables, listing the sources by IRAS name and by Auto Class class, are also given. These classes show some of the well known classes, such as the black-body class, and silicate emission classes, but many other classes were unsuspected, while others show important subtle differences within the well known classes.

  6. Mid-Infrared Silicate Dust Features in Seyfert 1 Spectra

    NASA Astrophysics Data System (ADS)

    Thompson, Grant D.; Levenson, N. A.; Sirocky, M. M.; Uddin, S.

    2007-12-01

    Silicate dust emission dominates the mid-infrared spectra of galaxies, and the dust produces two spectral features, at 10 and 18 μm. These features' strengths (in emission or absorption) and peak wavelengths reveal the geometry of the dust distribution, and they are sensitive to the dust composition. We examine mid-infrared spectra of 32 Seyfert 1 active galactic nuclei (AGN), observed with the Infrared Spectrograph aboard the Spitzer Space Telescope. In the spectra, we typically find the shorter-wavelength feature in emission, at an average peak wavelength of 10.0 μm, although it is known historically as the "9.7 μm" feature. In addition, peak wavelength increases with feature strength. The 10 and 18 μm feature strengths together are sensitive to the dust geometry surrounding the central heating engine. Numerical calculations of radiative transfer distinguish between clumpy and smooth distributions, and we find that the surroundings of these AGN (the obscuring "tori" of unified AGN schemes) are clumpy. Polycyclic aromatic hydrocarbon (PAH) features are associated with star formation, and we find strong PAH emission (luminosity ≥ 1042 erg/s) in only four sources, three of which show independent evidence for starbursts. We will explore the effects of luminosity on dust geometry and chemistry in a comparison sample of quasars. We acknowledge work supported by the NSF under grant number 0237291.

  7. The Mid-Infrared Transmission Spectra of Antarctic Ureilites

    NASA Technical Reports Server (NTRS)

    Sandford, Scott A.

    1993-01-01

    The mid-infrared (4000-450 1/cm; 2.5-22.2 micron) transmission spectra of seven Antarctic ureilites and 10 Antarctic H-5 ordinary chondrites are presented. The ureilite spectra show a number of absorption bands, the strongest of which is a wide, complex feature centered near 1000 1/cm (10 micron) due to Si-O stretching vibrations in silicates. The profiles and positions of the substructure in this feature indicate that Mg-rich olivines and pyroxenes are the main silicates responsible. The relative abundances of these two minerals, as inferred from the spectra, show substantial variation from meteorite to meteorite, but generally indicate olivine is the most abundant (olivine:pyroxene = 60:40 to 95:5). Both the predominance of olivine and the variable olivine-to-pyroxene ratio are consistent with the known composition and heterogeneity of ureilites. The H-5 ordinary chondrites spanned a range of weathering classes and were used to provide a means of addressing the extent to which the ureilite spectra may have been altered by weathering processes. It was found that, while weathering of these meteorites produces some weak bands due to the formation of small amounts of carbonates and hydrates, the profile of the main silicate feature has been little affected by Antarctic exposure in the meteorites studied here. The mid-infrared ureilite spectra provide an additional means of testing potential asteroidal parent bodies for the ureilites. At present, the best candidates include the subset of S-type asteroids having low albedos and weak absorption features in the near infrared.

  8. Iron in the Fire: Searching for Fire's Magnetic Fingerprint using Controlled Heating Experiments, High-Resolution FORCs, IRM Coercivity Spectra, and Low-Temperature Remanence Experiments

    NASA Astrophysics Data System (ADS)

    Lippert, P. C.; Reiners, P. W.

    2014-12-01

    Evidence for recent climate-wildfire linkages underscores the need for better understanding of relationships between wildfire and major climate shifts in Earth history, which in turn offers the potential for prognoses for wildfire and human adaptations to it. In particular, what are the links between seasonality and wildfire frequency and severity, and what are the feedbacks between wildfire, landscape evolution, and biogeochemical cycles, particularly the carbon and iron cycles? A key first step in addressing these questions is recovering well-described wildfire records from a variety of paleolandscapes and paleoclimate regimes. Although charcoal and organic biomarkers are commonly used indicators of fire, taphonomic processes and time-consuming analytical preparations often preclude their routine use in some environments and in high-stratigraphic resolution paleowildfire surveying. The phenomenological relationship between fire and magnetic susceptibility can make it a useful surveying tool, but increased magnetic susceptibility in sediments is not unique to fire, and thus limits its diagnostic power. Here we utilize component-specific rock magnetic methods and analytical techniques to identify the rock magnetic fingerprint of wildfire. We use a custom-designed air furnace, a series of iron-free laboratory soils, natural saprolites and soils, and fuels from Arizona Ponderosa pine forests and grasslands to simulate wildfire in a controlled and monitored environment. Soil-ash residues and soil and fuel controls were then characterized using First Order Reversal Curve (FORC) patterns, DC backfield IRM coercivity spectra, low-temperature SIRM demagnetization behavior, and low-temperature cycling of room-temperature SIRM behavior. We will complement these magnetic analyses with high-resolution TEM of magnetic extracts. Here we summarize the systematic changes to sediment magnetism as pyrolitized organic matter is incorporated into artificial and natural soils. These

  9. Multiwavelength optical observations of chromospherically active binary systems. III. High resolution echelle spectra from Ca II H & K to Ca II IRT

    NASA Astrophysics Data System (ADS)

    Montes, D.; Fernández-Figueroa, M. J.; De Castro, E.; Cornide, M.; Latorre, A.; Sanz-Forcada, J.

    2000-10-01

    This is the third paper of a series aimed at studying the chromosphere of active binary systems using the information provided for several optical spectroscopic features. High resolution echelle spectra including all the optical chromospheric activity indicators from the Ca II H & K to Ca II IRT lines are analysed here for 16 systems. The chromospheric contribution in these lines has been determined using the spectral subtraction technique. Very broad wings have been found in the subtracted Hα profile of the very active star HU Vir. These profiles are well matched using a two-component Gaussian fit (narrow and broad) and the broad component can be interpreted as arising from microflaring. Red-shifted absorption features in the Hα line have been detected in several systems and excess emission in the blue wing of FG UMa was also detected. These features indicate that several dynamical processes, or a combination of them, may be involved. Using the E_Hα /E_Hβ ratio as a diagnostic we have detected prominence-like extended material viewed off the limb in many stars of the sample, and prominences viewed against the disk at some orbital phases in the dwarfs OU Gem and BF Lyn. The He i D3 line has been detected as an absorption feature in mainly all the giants of the sample. Total filling-in of the He i D3, probably due to microflaring activity, is observed in HU Vir. Self-absorption with red asymmetry is detected in the Ca II H & K lines of the giants 12 Cam, FG UMa and BM CVn. All the stars analysed show clear filled-in Ca II IRT lines or even notable emission reversal. The small values of the E_8542/E_8498 ratio we have found indicate Ca II IRT emission arises from plage-like regions. Orbital phase modulation of the chromospheric emission has been detected in some systems, in the case of HU Vir evidence of an active longitude area has been found. Based on observations made with the Isaac Newton Telescope (INT) operated on the island of La Palma by the Isaac Newton

  10. Variability of visible and near-infrared spectra of rocks

    NASA Astrophysics Data System (ADS)

    Guo, Xiaofang; Wang, Runsheng; Cheng, Jicheng; Zhang, Zonnggui

    1998-08-01

    Although characteristics of visible and near-infrared spectra (0.4 - 2.5 micrometer) of rocks are dominated by electronic processes and molecular vibration processes that is related to chemical composition and structure of rocks, external behavior of spectra of rocks is adjusted by some factors, such as environmental conditions, physical structure of surface and viewing geometry, etc. The spectra of rocks can vary with the changes of these factors to a certain extent. It is obvious that variability of spectra of ground objects would degrade the interpretability of remote sensing images, and especially degrade the effectiveness of techniques of discriminating rocks based on remote sensing spectral features and spectral indexes to a large extent. To discriminate earth surface mineralogy and lithology more effectively and efficiently by remote sensing, especially by hyperspectral remote sensing, requires a good knowledge of variability of spectra of rocks. This paper describes and analyzes variability of reflectance spectra of rocks sampled in Zhangjiakou district of Hebei Province of China, under different light incident direction and incident angle, viewing direction and viewing angle, surface forms of rocks, grades of samples, and types and extents of weathering, etc.

  11. Infrared extinction spectra of some common liquid aerosols.

    PubMed

    Carlon, H R; Anderson, D H; Milham, M E; Tarnove, T L; Frickel, R H; Sindoni, I

    1977-06-01

    Infrared extinction spectra in the 3-5-microm and 7-13-microm atmospheric window regions have been obtained for smokes of petroleum oil, sulfuric acid, and phosphoric acid of varying droplet concentration and for water fogs. Spectra were also obtained at 0.36-2.35microm for petroleum oil and sulfuric acid smokes. Experimental results were compared, for sulfuric acid and water aerosols, to calculated values obtained from the Mie theory. Agreement was as good as +/-10%. When absorbing smoke droplets are small compared to wavelength, very useful approximations apply, and droplet clouds may be spectrally simulated by thin liquid films. In such cases, the imaginary component of refractive index may be approximated directly from aerosol spectra. At 12.5-microm wavelength, water fog extinction is nearly independent of droplet size distribution, suggesting a simple scheme for measurement of total liquid water content of an optical path. PMID:20168760

  12. Visible and Near Infrared Spectra of Five Near Earth Asteroids

    NASA Astrophysics Data System (ADS)

    Gietzen, Katherine M.; Lacy, C. H.; Rivkin, A. S.

    2006-06-01

    Reflectance spectra of five near earth asteroids (3908, 7753, 22771, 54509 and 66251) were obtained in the near infrared (.8 - 2.5 µm) using the NASA IRTF equipped with the SpEX infrared spectrometer at Mauna Kea in 2004 and 2005. The data obtained was coupled with spectral data in the visible wavelengths from the SMASS database [2, 3, 4, and 5] and analyzed using the Modified Gaussian Model (MGM). The expected absorption bands at 1 and 2 µm for olivines and pyroxenes were observed in a number of the asteroid spectra. However, we also found that there were asteroid reflectance spectra that were very featureless and the absorption bands that were present (if any) were very weak. Space weathering has been given by others [1} as a possible explanation for the lack of absorption features in the spectra of asteroids. This space weathering has been described to be the possible result of the processes of sputtering erosion as a result of the impacts and implantations, radiation and cosmic ray effects. Asteroid 1989 ML (10302) was also studied using SMASS observation data in the visible wavelengths. The reflectance spectra was compared to the spectra of various types of meteorites in an attempt find a match that would aid in the classification of 1989 MLReferences: [1] B. Hapke (2001) J. Geophys. Res. 106, 10039-10073; [2] J.T. Rayner et al. (2003) PASP 115, 362; [3] R.P. Binzel et al. (2004) Icarus 170, 259-294; [4] R.P. Binzel et al. (2004) Meteoritics and Planetary Science 39, 354-366; [5] T.H. Burbine et al. (2002) Icarus 159, 468-499

  13. The far-infrared spectrum of azulene and isoquinoline and supporting anharmonic density functional theory calculations to high resolution spectroscopy of polycyclic aromatic hydrocarbons and derivatives

    NASA Astrophysics Data System (ADS)

    Goubet, Manuel; Pirali, Olivier

    2014-01-01

    In the laboratory, the acquisition and analysis of the rotationally resolved spectra of large molecular systems remain challenging. We report in this paper the rotational analysis of the ν30-GS band of azulene and the ν41-GS band of isoquinoline recorded with synchrotron-based Fourier transform absorption spectroscopy in the far-IR. As a support to rotational analyses, we employed a method based on standard density functional theory calculations performed at the anharmonic level which accurately reproduced the rotational constants of 28 vibrational states of 16 Polycyclic Aromatic Hydrocarbons (PAHs) and aza-derivatives. This method appears as an invaluable support for the spectral assignment of the very congested rotational structures of the infrared bands of PAH species and should be very helpful in the active search of these molecules in space through their pure rotational or rovibrational spectra.

  14. Thermal signatures of urban land cover types: High-resolution thermal infrared remote sensing of urban heat island in Huntsville, AL

    NASA Technical Reports Server (NTRS)

    Lo, Chor Pang

    1996-01-01

    The main objective of this research is to apply airborne high-resolution thermal infrared imagery for urban heat island studies, using Huntsville, AL, a medium-sized American city, as the study area. The occurrence of urban heat islands represents human-induced urban/rural contrast, which is caused by deforestation and the replacement of the land surface by non-evaporating and non-porous materials such as asphalt and concrete. The result is reduced evapotranspiration and more rapid runoff of rain water. The urban landscape forms a canopy acting as a transitional zone between the atmosphere and the land surface. The composition and structure of this canopy have a significant impact on the thermal behavior of the urban environment. Research on the trends of surface temperature at rapidly growing urban sites in the United States during the last 30 to 50 years suggests that significant urban heat island effects have caused the temperatures at these sites to rise by 1 to 2 C. Urban heat islands have caused changes in urban precipitation and temperature that are at least similar to, if not greater than, those predicted to develop over the next 100 years by global change models. Satellite remote sensing, particularly NOAA AVHRR thermal data, has been used in the study of urban heat islands. Because of the low spatial resolution (1.1 km at nadir) of the AVHRR data, these studies can only examine and map the phenomenon at the macro-level. The present research provides the rare opportunity to utilize 5-meter thermal infrared data acquired from an airplane to characterize more accurately the thermal responses of different land cover types in the urban landscape as input to urban heat island studies.

  15. Mapping bare soil in South West Wales, UK, using high resolution colour infra-red aerial photography for water quality and flood risk management applications

    NASA Astrophysics Data System (ADS)

    Sykes, Helena; Neale, Simon; Coe, Sarah

    2016-04-01

    Natural Resources Wales is a UK government body responsible for environmental regulation, among other areas. River walks in Water Framework Directive (WFD) priority catchments in South West Wales, UK, identified soil entering water courses due to poaching and bank erosion, leading to deterioration in the water quality and jeopardising the water quality meeting legal minimum standards. Bare soil has also been shown to cause quicker and higher hydrograph peaks in rural catchments than if those areas were vegetated, which can lead to flooding of domestic properties during peak storm flows. The aim was to target farm visits by operational staff to advise on practices likely to improve water quality and to identify areas where soft engineering solutions such as revegetation could alleviate flood risk in rural areas. High resolution colour-infrared aerial photography, 25cm in the three colour bands and 50cm in the near infrared band, was used to map bare soil in seven catchments using supervised classification of a five band stack including the Normalised Difference Vegetation Index (NDVI). Mapping was combined with agricultural land use and field boundary data to filter out arable fields, which are supposed to bare soil for part of their cycle, and was very successful when compared to ground truthing, with the exception of silage fields which contained sparse, no or unproductive vegetation at the time the imagery was acquired leading to spectral similarity to bare soil. A raindrop trace model was used to show the path sediment from bare soil areas would take when moving through the catchment to a watercourse, with hedgerows inserted as barriers following our observations from ground truthing. The findings have been used to help farmers gain funding for improvements such as fencing to keep animals away from vulnerable river banks. These efficient and automated methods can be rolled out to more catchments in Wales and updated using aerial imagery acquired more recently to

  16. Trade-off study for high resolution spectroscopy in the near infrared with ELT telescopes: seeing-limited vs. diffraction limited instruments

    NASA Astrophysics Data System (ADS)

    Sanna, Nicoletta; Oliva, E.; Massi, Fabrizio; Cresci, G.; Origlia, L.

    2014-08-01

    HIRES, a high resolution spectrometer, is one of the first five instruments foreseen in the ESO roadmap for the E-ELT. This spectrograph should ideally provide full spectral coverage from the UV limit to 2.5 microns, with a resolving power from R˜10,000 to R˜100,000. At visual/blue wavelengths, where the adaptive optics (AO) cannot provide an efficient light-concentration, HIRES will necessarily be a bulky, seeing-limited instrument. The fundamental question, which we address in this paper, is whether the same approach should be adopted in the near-infrared range, or HIRES should only be equipped with compact infrared module(s) with a much smaller aperture, taking advantage of an AO-correction. The main drawbacks of a seeing-limited instrument at all wavelengths are: i) Lower sensitivities at wavelengths dominated by thermal background (red part of the K-band). ii) Much higher volumes and costs for the IR spectrograph module(s). The main drawbacks of using smaller, AO-fed IR module(s) are: i) Performances rapidly degrading towards shorter wavelengths (especially J e Y bands). ii) Different spatial sampling of extended objects (the optical module see a much larger area on the sky). In this paper we perform a trade-off analysis and quantify the various effects that contribute to improve or deteriorate the signal to noise ratio. In particular, we evaluate the position of the cross-over wavelength at which AO-fed instruments starts to outperform seeing-limited instruments. This parameter is of paramount importance for the design of the part of HIRES covering the K-band.

  17. Performance of the Apache Point Observatory Galactic Evolution Experiment (APOGEE) high-resolution near-infrared multi-object fiber spectrograph

    NASA Astrophysics Data System (ADS)

    Wilson, John C.; Hearty, F.; Skrutskie, M. F.; Majewski, S. R.; Schiavon, R.; Eisenstein, D.; Gunn, J.; Holtzman, J.; Nidever, D.; Gillespie, B.; Weinberg, D.; Blank, B.; Henderson, C.; Smee, S.; Barkhouser, R.; Harding, A.; Hope, S.; Fitzgerald, G.; Stolberg, T.; Arns, J.; Nelson, M.; Brunner, S.; Burton, A.; Walker, E.; Lam, C.; Maseman, P.; Barr, J.; Leger, F.; Carey, L.; MacDonald, N.; Ebelke, G.; Beland, S.; Horne, T.; Young, E.; Rieke, G.; Rieke, M.; O'Brien, T.; Crane, J.; Carr, M.; Harrison, C.; Stoll, R.; Vernieri, M.; Shetrone, M.; Allende-Prieto, C.; Johnson, J.; Frinchaboy, P.; Zasowski, G.; Garcia Perez, A.; Bizyaev, D.; Cunha, K.; Smith, V. V.; Meszaros, Sz.; Zhao, B.; Hayden, M.; Chojnowski, S. D.; Andrews, B.; Loomis, C.; Owen, R.; Klaene, M.; Brinkmann, J.; Stauffer, F.; Long, D.; Jordan, W.; Holder, D.; Cope, F.; Naugle, T.; Pfaffenberger, B.; Schlegel, D.; Blanton, M.; Muna, D.; Weaver, B.; Snedden, S.; Pan, K.; Brewington, H.; Malanushenko, E.; Malanushenko, V.; Simmons, A.; Oravetz, D.; Mahadevan, S.; Halverson, S.

    2012-09-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) uses a dedicated 300-fiber, narrow-band near-infrared (1.51-1.7 μm), high resolution (R~22,500) spectrograph to survey approximately 100,000 giant stars across the Milky Way. This three-year survey, in operation since late-summer 2011 as part of the Sloan Digital Sky Survey III (SDSS III), will revolutionize our understanding of the kinematical and chemical enrichment histories of all Galactic stellar populations. We present the performance of the instrument from its first year in operation. The instrument is housed in a separate building adjacent to the 2.5-m SDSS telescope and fed light via approximately 45-meter fiber runs from the telescope. The instrument design includes numerous innovations including a gang connector that allows simultaneous connection of all fibers with a single plug to a telescope cartridge that positions the fibers on the sky, numerous places in the fiber train in which focal ratio degradation had to be minimized, a large mosaic-VPH (290 mm x 475 mm elliptically-shaped recorded area), an f/1.4 six-element refractive camera featuring silicon and fused silica elements with diameters as large as 393 mm, three near-infrared detectors mounted in a 1 x 3 mosaic with sub-pixel translation capability, and all of these components housed within a custom, LN2-cooled, stainless steel vacuum cryostat with dimensions 1.4-m x 2.3-m x 1.3-m.

  18. High resolution infrared synchrotron study of CH2D81Br: ground state constants and analysis of the ν5, ν6 and ν9 fundamentals

    NASA Astrophysics Data System (ADS)

    Baldacci, A.; Stoppa, P.; Visinoni, R.; Wugt Larsen, R.

    2012-09-01

    The high resolution infrared absorption spectrum of CH2D81Br has been recorded by Fourier transform spectroscopy in the range 550-1075 cm-1, with an unapodized resolution of 0.0025 cm-1, employing a synchrotron radiation source. This spectral region is characterized by the ν6 (593.872 cm-1), ν5 (768.710 cm-1) and ν9 (930.295 cm-1) fundamental bands. The ground state constants up to sextic centrifugal distortion terms have been obtained for the first time by ground-state combination differences from the three bands and subsequently employed for the evaluation of the excited state parameters. Watson's A-reduced Hamiltonian in the Ir representation has been used in the calculations. The ν 6 = 1 level is essentially free from perturbation whereas the ν 5 = 1 and ν 9 = 1 states are mutually interacting through a-type Coriolis coupling. Accurate spectroscopic parameters of the three excited vibrational states and a high-order coupling constant which takes into account the interaction between ν5 and ν9 have been determined.

  19. The infrared spectrum of isothiazole in the range 600-1500 cm-1, including a high-resolution study of the ν studies of the full spectrum

    NASA Astrophysics Data System (ADS)

    Hegelund, F.; Wugt Larsen, R.; Aitken, R. A.; Kraus, H.; Nicolaisen, F. M.; Palmer, M. H.

    The gas-phase high-resolution infrared spectrum of isothiazole in the range 600-1500 cm-1 has been recorded, and revised band centres obtained for a number of vibrations. An analysis of the ν11(A') band at 818 cm-1 and the ν16(A'') band at 727 cm-1 has been performed, using the Watson Hamiltonian, A-reduction, IIIr representation. These were combined with previous microwave spectral data to provide combined analyses for rotational constants and quartic centrifugal distortion constants ΔJ, ΔJK, ΔK, δJ and δK. These extend the knowledge derived from previous microwave and IR spectral studies. The equilibrium structures and the derived harmonic frequencies were calculated by ab initio methods, using a variety of basis sets with MP2, MP4 and CCSD(T) methods, and a comparison of these with experimental data is discussed. At a pragmatic level, the closest correlation of the rotational constants with experiment is not obtained with the most sophisticated methodology. Similarly, the vibration frequencies and intensities also vary strongly with the procedure. In particular, we found that the cc-pVTZ+MP2 results probably provide the best numerical comparison with experimental IR data for this molecule.

  20. Feedback in the Antennae Galaxies (NGC 4038/9): I. High-Resolution Infrared Spectroscopy of Winds from Super Star Clusters

    SciTech Connect

    Gilbert, A; Graham, J

    2007-06-05

    We present high-resolution (R {approx} 24,600) near-IR spectroscopy of the youngest super star clusters (SSCs) in the prototypical starburst merger, the Antennae Galaxies. These SSCs are young (3-7 Myr old) and massive (10{sup 5}-10{sup 7} M{sub {circle_dot}} for a Kroupa IMF) and their spectra are characterized by broad, extended Brackett {gamma} emission, so we refer to them as emission-line clusters (ELCs) to distinguish them from older SSCs. The Br {gamma} lines of most ELCs have supersonic widths (60-110 km s{sup -1} FWHM) and non-Gaussian wings whose velocities exceed the clusters escape velocities. This high-velocity unbound gas is flowing out in winds that are powered by the clusters massive O and W-R stars over the course of at least several crossing times. The large sizes of some ELCs relative to those of older SSCs may be due to expansion caused by these outflows; many of the ELCs may not survive as bound stellar systems, but rather dissipate rapidly into the field population. The observed tendency of older ELCs to be more compact than young ones is consistent with the preferential survival of the most concentrated clusters at a given age.

  1. High-resolution solid-state 13C CP MAS NMR spectra of some β-cyclodextrin inclusion complexes with nitriles

    NASA Astrophysics Data System (ADS)

    Okazaki, M.; McDowell, C. A.

    1983-11-01

    β-cyclodextrin inclusion complexes of 3-aminobenzonitrile, 4-aminobenzonitrile, and adamantane-1-carbonitrile were studied by means of high-resolution solid-state CP MAS 13C NMR spectroscopy. The interactions between the host and guest molecules are discussed.

  2. Infrared reflectance spectra: Effects of particle size, provenance and preparation

    SciTech Connect

    Su, Yin-Fong; Myers, Tanya L.; Brauer, Carolyn S.; Blake, Thomas A.; Forland, Brenda M.; Szecsody, James E.; Johnson, Timothy J.

    2014-09-22

    We have recently developed methods for making more accurate infrared total and diffuse directional - hemispherical reflectance measurements using an integrating sphere. We have found that reflectance spectra of solids, especially powders, are influenced by a number of factors including the sample preparation method, the particle size and morphology, as well as the sample origin. On a quantitative basis we have investigated some of these parameters and the effects they have on reflectance spectra, particularly in the longwave infrared. In the IR the spectral features may be observed as either maxima or minima: In general, upward-going peaks in the reflectance spectrum result from strong surface scattering, i.e. rays that are reflected from the surface without bulk penetration, whereas downward-going peaks are due to either absorption or volume scattering, i.e. rays that have penetrated or refracted into the sample interior and are not reflected. The light signals reflected from solids usually encompass all such effects, but with strong dependencies on particle size and preparation. This paper measures the reflectance spectra in the 1.3 – 16 micron range for various bulk materials that have a combination of strong and weak absorption bands in order to observe the effects on the spectral features: Bulk materials were ground with a mortar and pestle and sieved to separate the samples into various size fractions between 5 and 500 microns. The median particle size is demonstrated to have large effects on the reflectance spectra. For certain minerals we also observe significant spectral change depending on the geologic origin of the sample. All three such effects (particle size, preparation and provenance) result in substantial change in the reflectance spectra for solid materials; successful identification algorithms will require sufficient flexibility to account for these parameters.

  3. IRAS high resolution studies and modeling of closely interacting galaxies. Galaxy collisions: Infrared observations and analysis of numerical models. UV spectroscopy of massive young stellar populations in interacting galaxies

    NASA Technical Reports Server (NTRS)

    Lamb, Susan A.

    1993-01-01

    The Final Technical Report covering the period from 15 Aug. 1989 to 14 Aug. 1991 is presented. Areas of research included Infrared Astronomy Satellite (IRAS) high resolution studies and modeling of closely interacting galaxies; galaxy collisions: infrared observations and analysis of numerical models; and UV spectroscopy of massive young stellar populations in interacting galaxies. Both observational studies and theoretical modelling of interacting galaxies are covered. As a consequence the report is divided into two parts, one on each aspect of the overall project.

  4. Infrared spectra of molecules and materials of astrophysical interest

    NASA Technical Reports Server (NTRS)

    Durig, J. R.

    1978-01-01

    The Raman spectra of gaseous, liquid and solid, and infrared spectra of gaseous and solid isopropylamine-d sub 0 and -d sub 2 was investigated between 4000 and 50 cm superscript -1. Differences between the spectrum of the solid phase and that of the fluid phases were interpreted in terms of an equilibrium between low energy s-trans and high energy gauche conformers, and a complete vibrational assignment was proposed for the s-trans conformer. The far infrared spectra of the gaseous compounds contained bands due to the asymmetric amino and coupled methyl torsions; the assignment of these bands was aided by observation of a number of two quantum transitions for each vibrational mode. The asymmetric potential functions were calculated, which resulted in values for the enthalpy differences between conformers in the gaseous phase of 446 and 523 callmole for the sub 0 -d and -d sub 2 compounds, respectively. The methyl torsional potential function of isopropylamine-d sub 0 was calculated which led to a value for the barrier height to internal rotation of the methyl rotors of 4.23 + or - 0.06 kcal/mole. Values for the ideal gas thermodynamic functions were calculated over a range of temperatures.

  5. Infrared spectra of meteoritic SiC grains

    NASA Astrophysics Data System (ADS)

    Andersen, A. C.; Jäger, C.; Mutschke, H.; Braatz, A.; Clément, D.; Henning, Th.; Jørgensen, U. G.; Ott, U.

    1999-03-01

    We present here the first infrared spectra of meteoritic SiC grains. The mid-infrared transmission spectra of meteoritic SiC grains isolated from the Murchison meteorite were measured in the wavelength range 2.5-16.5 mu m, in order to make available the optical properties of presolar SiC grains. These grains are most likely stellar condensates with an origin predominately in carbon stars. Measurements were performed on two different extractions of presolar SiC from the Murchison meteorite. The two samples show very different spectral appearance due to different grain size distributions. The spectral feature of the smaller meteoritic SiC grains is a relatively broad absorption band found between the longitudinal and transverse lattice vibration modes around 11.3 mu m, supporting the current interpretation about the presence of SiC grains in carbon stars. In contrast to this, the spectral feature of the large (> 5 mu m) grains has an extinction minimum around 10 mu m. The obtained spectra are compared with commercially available SiC grains and the differences are discussed. This comparison shows that the crystal structure (e.g., beta -SiC versus alpha -SiC) of SiC grains plays a minor role on the optical signature of SiC grains compared to e.g. grain size.

  6. Low-Temperature High-Resolution Infrared Spectrum of ETHANE-1D, C_2H_5D: Rotational Analysis of the νb{17} Band Near 805 wn using Erham.

    NASA Astrophysics Data System (ADS)

    Groner, Peter; Daly, Adam M.; Drouin, Brian; Pearson, John; Sung, Keeyoon; Brown, Linda; Mantz, Arlan; Smith, Mary Ann H.

    2015-06-01

    The high-resolution infrared spectrum of gaseous ethane-d1 at 130 K shows transitions that are split into A and E components due to the interaction of overall rotation with the internal rotation of the CH_3 group. An analysis of the spectrum from 680 to 900 wn with an expanded version of the program ERHAM is in progress to assign the bands at E(νb{17}) = 805 wn and E(νb{11}) = 715 wn. A discussion of the interactions among the fundamental levels of νb{17} and νb{11} with overtone levels of νb{18} and the(CH_3 torsion) will be given. ERHAM has been and continues to be very successful in the analysis of pure the rotational spectra of molecules containing internal rotation and the vibrational spectrum of C_2H_5D serves as an excellent system to test the extension of the program. P. Groner, J. Chem. Phys. 107 4483 (1997) P. Groner, J. Mol. Spectrosc. 278 52 (2012)

  7. A high resolution far-infrared survey of a section of the galactic plane. II - Far-infrared, CO, and radio continuum results

    NASA Technical Reports Server (NTRS)

    Stier, M. T.; Fazio, G. G.; Roberge, W. G.; Thum, C.; Wilson, T. L.; Jaffe, D. T.

    1982-01-01

    An area of 7.5 sq deg of the galactic plane at 70 microns have been surveyed with a 1-arcmin beam. The region lies between lII equals 10 deg and lII equals 16 deg and includes the M17 and W33 complexes. The weakest of the 42 sources detected had a flux density of 350 Jy at 70 microns. Detailed far-infrared, (C-12)O, (C-13)O, and radio continuum observations of the sources are presented. The derivation of the important physical parameters of the sources and their surrounding molecular clouds are discussed. The properties of the individual regions are also discussed and maps of selected sources are presented.

  8. High resolution far-infrared survey of a section of the galactic plane. II. Far-infrared, CO, and radio continuum results

    SciTech Connect

    Stier, M.T.; Jaffe, D.T.; Fazio, G.G.; Roberge, W.G.; Thum, C.; Wilson, T.L.

    1982-01-01

    We have surveyed 7.5 deg/sup 2/ of the galactic plane at 70 ..mu..m with a approx.1' beam (Jaffe, Stier, and Fazio). The region lies between l/sup i/I = 10/sup 0/ and l/sup i/I = 16/sup 0/ and includes the M17 and W33 complexes. The weakest of the 42 sources detected had a flux density of 350 Jy at 70 ..mu..m. We present detailed far-infrared, /sup 12/CO, /sup 13/CO, and radio continuum observations of these sources. We discuss the derivation of the important physical parameters of the sources and their surrounding molecular clouds. We also discuss the properties of the individual regions and present maps of selected sources.

  9. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Benner, D. Chris; Venkataraman, Malathy Devi

    2000-01-01

    The major research activities performed during the cooperative agreement enhanced our spectroscopic knowledge of molecules of atmospheric interest such as carbon dioxide, water vapor, ozone, methane, and carbon monoxide, to name a few. Measurements were made using the NASA Langley Tunable Diode Laser Spectrometer System (TDL) and several Fourier Transform Spectrometer Systems (FTS) around the globe. The results from these studies made remarkable improvements in the line positions and intensities for several molecules, particularly ozone and carbon dioxide in the 2 to 17-micrometer spectral region. Measurements of pressure broadening and pressure induced line shift coefficients and the temperature dependence of pressure broadening and pressure induced line shift coefficients for infrared transitions of ozone, methane, and water vapor were also performed. Results from these studies have been used for retrievals of stratospheric gas concentration profiles from data collected by several Upper Atmospheric Research satellite (UARS) infrared instruments as well as in the analysis of high resolution atmospheric spectra such as those acquired by space-based, ground-based, and various balloon- and aircraft-borne experiments. Our results made significant contributions in several updates of the HITRAN (HIgh resolution TRANsmission) spectral line parameters database. This database enjoys worldwide recognition in research involving diversified scientific fields.

  10. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Benner, D. Chris; Venkataraman, Malathy Devi

    2000-01-01

    The major research activities performed during the cooperative agreement enhanced our spectroscopic knowledge of molecules of atmospheric interest such as carbon dioxide, water vapor, ozone, methane, and carbon monoxide, to name a few. Measurements were made using the NASA Langley Tunable Diode Laser Spectrometer System (TDL) and several Fourier Transform Spectrometer Systems (FTS) around the globe. The results from these studies made remarkable improvements in the line positions and intensities for several molecules, particularly ozone and carbon dioxide in the 2 to 17-micrometer spectral region. Measurements of pressure broadening and pressure induced line shift coefficients and the temperature dependence of pressure broadening and pressure induced line shift coefficients for infrared transitions of ozone, methane, and water vapor were also performed. Results from these studies have been used for retrievals of stratospheric gas concentration profiles from data collected by several Upper Atmospheric Research satellite (UARS) infrared instruments as well as in the analysis of high resolution atmospheric spectra such as those acquired by space-based, ground-based, and various balloon-and aircraft-borne experiments. Our results made significant contributions in several updates of the HITRAN (HIgh resolution TRANsmission) spectral line parameters database. This database enjoys worldwide recognition in research involving diversified scientific fields.

  11. Mid-infrared spectra of Class I protostars in Taurus

    NASA Astrophysics Data System (ADS)

    Green, J. D.; Watson, D. M.; Furlan, E.; Forrest, W. J.; Chen, C. H.; Kemper, F.; Calvet, N.; Hartmann, L.; Uchida, K. I.; Keller, L. D.; Sargent, B.; Sloan, G. C.; Herter, T. L.; Brandl, B. R.; Houck, J. R.; Barry, D. J.; Hall, P.; Morris, P. W.; Jura, M.; Najita, J.; D'Alessio, P.; Myers, P. C.

    2004-05-01

    We present Spitzer Infrared Spectrograph (IRS)* observations in the 5.3-20 μ m range of five young stellar objects in Taurus that have Class I continuum spectral energy distributions, often taken to represent the younger stellar objects in this star-formation region. The spectra include a rich collection of broad absorption features that we identify with amorphous silicates and various ices, notably those of water, methanol, and carbon dioxide. This is apparently the first detection of such ice features in the disks of low-mass (below a solar mass) young stellar objects. We use these spectral features to estimate the relative contributions of disk and envelope to the absorption spectrum, and compare the spectra to detailed models to derive a view of the thermal structure of these components of circumstellar material. We conclude that the objects represent a range of envelope mass and line-of-sight orientation, and that objects can be classified in terms of these properties from mid-infrared spectra, even in the absence of supporting information from infrared images. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA through Contract Number 1257184 issued by JPL/Caltech, and through the Spitzer Fellowship Program, under award 011 808-001. * The IRS was a collaborative venture between Cornell University and Ball Aerospace Corporation funded by NASA through the Jet Propulsion Laboratory and the Ames Research Center.

  12. Infrared, Polarized Raman, and SERS Spectra of Borax

    NASA Astrophysics Data System (ADS)

    Devi, S. Arya; Philip, Daizy; Aruldhas, G.

    1994-11-01

    Infrared and polarized Raman spectra of Na2B4O7 · 10H2O are recorded and analyzed. The vibrational assignments are made on the basis of vibrations due to BO4 and BO3 groups, water molecules, and (B)OH bonds. Three types of water molecules exist in the crystal, and the BO4 groups are considerably distorted. Band assignments are confirmed by deuterium substitution. A SERS spectrum recorded in a silver colloid shows three enhanced bands at 800, 480, and 464 cm-1.

  13. Prognosis of chronic lymphocytic leukemia from infrared spectra of lymphocytes

    NASA Astrophysics Data System (ADS)

    Schultz, Christian P.; Liu, Kan-Zhi; Johnston, James B.; Mantsch, Henry H.

    1997-06-01

    Peripheral mononuclear cells obtained from blood of normal individuals and from patients with chronic lymphocytic leukemia (CLL) were investigated by infrared spectroscopy and multivariate statistical analysis. Not only are the spectra of CLL cells different from those of normal cells, but hierarchical clustering also separated the CLL cells into a number of subclusters, based on their different DNA content, a fact which may provide a useful diagnostic tool for staging (progression of the disease) and multiple clone detection. Moreover, there is evidence for a correlation between the increased amount of DNA in the CLL cells and the in-vivo doubling time of the lymphocytes in a given patient.

  14. Compositional stratigraphy of crustal material from near-infrared spectra

    NASA Technical Reports Server (NTRS)

    Pieters, Carle M.

    1987-01-01

    An Earth-based telescopic program to acquire near-infrared spectra of freshly exposed lunar material now contains data for 17 large impact craters with central peaks. Noritic, gabbroic, anorthositic and troctolitic rock types can be distinguished for areas within these large craters from characteristic absorptions in individual spectra of their walls and central peaks. Norites dominate the upper lunar crust while the deeper crustal zones also contain significant amounts of gabbros and anorthosites. Data for material associated with large craters indicate that not only is the lunar crust highly heterogeneous across the nearside, but that the compositional stratigraphy of the lunar crust is nonuniform. Crustal complexity should be expected for other planetary bodies, which should be studied using high spatial and spectral resolution data in and around large impact craters.

  15. Infrared emission spectra from operating elastohydrodynamic sliding contacts

    NASA Technical Reports Server (NTRS)

    Lauer, J. L.

    1976-01-01

    Infrared emission spectra from an operating EHD sliding contact were obtained through a diamond window for an aromatic polymer solute present in equal concentration in four different fluids. Three different temperature ranges, three different loads, and three different speeds for every load were examined. Very sensitive Fourier spectrophotometric (Interferometric) techniques were employed. Band Intensities and band intensity ratios found to depend both on the operating parameters and on the fluid. Fluid film and metal surface temperatures were calculated from the spectra and their dependence on the mechanical parameters plotted. The difference between these temperatures could be plotted against shear rate on one curve for all fluids. However, at the same shear rate the difference between bulk fluid temperature and diamond window temperature was much higher for one of the fluids, a traction fluid, than for the others.

  16. The Influence of Particle Size on Infrared Reflectance Spectra

    SciTech Connect

    Myers, Tanya L.; Brauer, Carolyn S.; Su, Yin-Fong; Blake, Thomas A.; Johnson, Timothy J.; Richardson, Robert L.

    2014-06-13

    Reflectance spectra of solids are influenced by the absorption coefficient as well as the particle size and morphology. In the infrared, spectral features may be observed as either maxima or minima: in general, the upward-going peaks in the reflectance spectrum result from surface scattering, which are rays that have reflected from the surface without penetration, whereas downward-going peaks result from either absorption or volume scattering, i.e. rays that have penetrated into the sample or refracted into the sample interior and are not reflected. The light signal reflected from solids usually encompasses all these effects which include dependencies on particle size, morphology and sample density. This paper measures the reflectance spectra in the 1.3 – 16 micron range for various bulk materials that have a combination of strong and weak absorption bands in order to understand the effects on the spectral features as a function of the mean grain size of the sample. The bulk materials were ground with a mortar and pestle and then sieved to separate the samples into various size fractions: 0-45, 45-90, 90-180, 180-250, 250-500, and >500 microns. The directional-hemispherical spectra were recorded using a Fourier transform infrared spectrometer equipped with an integrating sphere to measure the reflectance for all of the particle-size fractions. We have studied both organic and inorganic materials, but this paper focuses on inorganic salts, NaNO3 in particular. Our studies clearly show that particle size has an enormous influence on the measured reflectance spectra for bulk materials and that successful identification requires sufficient representative reflectance data so as to include the particle size(s) of interest. Origins of the effects are discussed.

  17. Simulation of transient infrared spectra of a photoswitchable peptide.

    PubMed

    Kobus, Maja; Lieder, Martin; Nguyen, Phuong H; Stock, Gerhard

    2011-12-14

    In transient infrared (IR) experiments, a molecular system may be photoexcited in a nonstationary conformational state, whose time evolution is monitored via IR spectroscopy with high temporal and structural resolution. As a theoretical formulation of these experiments, this work derives explicit expressions for transient one- and two-dimensional IR spectra and discusses various levels of approximation and sampling strategies. Adopting a photoswitchable octapeptide in water as a representative example, nonequilibrium molecular dynamics simulations are performed and the photoinduced conformational dynamics and associated IR spectra are discussed in detail. Interestingly, it is found that the time scales of dynamics and spectra may differ from residue to residue by up to an order of magnitude. Considering merely the cumulative spectrum of all residues, the contributions of the individual residues largely compensate each other, which may explain the surprisingly small frequency shifts and short photoproduct rise times found in experiment. Even when a localized amide I mode is probed (e.g., via isotope labeling), the vibrational frequency shift is shown to depend in a complicated way on the conformation of the entire peptide as well as on the interaction with the solvent. In this context, various issues concerning the interpretation of transient IR spectra and conformational dynamics in terms of a few exponential time scales are discussed. PMID:22168727

  18. Infrared-Vacuum Ultraviolet Pulsed Field Ionization-Photoelectron Study of C₂H₄ + Using a High-Resolution Infrared Laser

    SciTech Connect

    Xing, Xi; Reed, Beth; Bahng, Mi-Kyung; Ng, Cheuk-Yiu

    2008-02-20

    The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. The infrared (IR)-vacuum ultraviolet (VUV)-pulsed field ionization-photoelectron (IR-VUV-PFI-PE) spectrum for C₂H₄(X 1Ag, V11 = 1, N'Ka'Kc'=3₀₃) in the VUV range of 83 000-84 800 cm-1 obtained using a single mode infrared laser revealed 24 rotationally resolved vibrational bands for the ion C₂H₄ +(X 2B3u) ground state. The frequencies and symmetry of the vibrational bands thus determined, together with the anharmonic frequency predictions calculated at the CCSD(T)/aug-cc-pVQZ level, have allowed the unambiguous assignment of these vibrational bands. These bands are mostly combination bands. The measured frequencies of these bands yield the fundamental frequencies for V8 + ) 1103± ( 10 cm-1 and V10 + ) 813 ( 10 cm-1 of C₂H₄ +(X 2B3u), which have not been determined previously. The present IR-VUV-PFI-PE study also provides truly rovibrationally selected and resolved state-to-state cross sections for the photoionization transitions C₂H₄(X~1Ag; V11, N'Ka'Kc') → C₂H₄ +(X~ 2B3u; Vi +, N+ Ka +Kc +), where N'Ka'Kc' denotes the rotational level of C₂H₄(X~ 1Ag; V11), and Vi + and N+ Ka +Kc + represent the vibrational and rotational states of the cation.

  19. Validation of the GOSAT Thermal Infrared (TIR) Band using the University of Wisconsin airborne Scanning High-resolution Interferometer Sounder (S-HIS) and ground-based Atmospheric Emitted Radiance Interferometer (AERI) at Railroad Valley, Nevada

    NASA Astrophysics Data System (ADS)

    Knuteson, R.; kuze, A.; Shiomi, K.; Taylor, J. K.; Garms, E.; Roman, J.; Revercomb, H. E.; Tobin, D. C.; Gero, P.; Best, F. A.

    2011-12-01

    We provide a quantitative assessment of the calibration accuracy of the thermal infrared measurements from the Greenhouse Gases Observing SATellite (GOSAT), which was launched on January 23, 2009. Results will be presented comparing the observed emission spectra from the TANSO-FTS sensor onboard GOSAT to coincident observations from high altitude aircraft and ground-based spectrometers during the June 2011 Railroad Valley Vicarious Calibration and Validation campaign. The 2011 campaign was the third in a series of joint Japan/U.S. field measurements to assess the calibration of the GOSAT sensors and validate derived products of carbon dioxide and methane. As part of the 2011 campaign, the University of Wisconsin Scanning High-resolution Interferometer Sounder (S-HIS) successfully overflew Railroad Valley, Nevada onboard the high-altitude NASA ER-2 along with the Airborne Visible/InfraRed Imaging Spectrometer (AVIRIS) and the MODIS/ASTER Airborne Simulator (MASTER). The ER-2 overpass of Railroad Valley on June 20, 2011 was timed to coincide with an overpass of the GOSAT satellite at 21:19 UTC. A joint JPL/UWisc team provided coincident upper air observations of pressure, temperature, and water vapor using Vaisala radiosondes released from the center of the Railroad Valley dry lakebed (playa) for six GOSAT daytime overpasses and three nighttime overpasses between 19-26 June 2011. The University of Wisconsin also made ground-based measurements from the center of the playa during each GOSAT overpass with an Atmospheric Emitted Radiance Interferometer. The AERI was operated from a research vehicle with the capability to measure the upwelling surface radiance at three view angles and the downwelling atmospheric emission at two angles. The ground-based AERI provided accurate surface emissivity and surface temperature for use in forward model calculations of the satellite observed infrared emission between 6 and 17 microns.

  20. Emerging trends and a comet taxonomy based on the volatile chemistry measured in thirty comets with high-resolution infrared spectroscopy between 1997 and 2013

    NASA Astrophysics Data System (ADS)

    Dello Russo, Neil; Kawakita, Hideyo; Vervack, Ronald J.; Weaver, Harold A.

    2016-11-01

    A systematic analysis of the mixing ratios with respect to H2O for eight species (CH3OH, HCN, NH3, H2CO, C2H2, C2H6, CH4, and CO) measured with high-resolution infrared spectroscopy in thirty comets between 1997 and 2013 is presented. Some trends are beginning to emerge when mixing ratios in individual comets are compared to average mixing ratios obtained for all species within the population. The variation in mixing ratios for all measured species is at least an order of magnitude. Overall, Jupiter-family comets are depleted in volatile species with respect to H2O compared to long-period Oort cloud comets, with the most volatile species showing the greatest relative depletion. There is a high positive correlation between the mixing ratios of HCN, C2H6, and CH4, whereas NH3, H2CO, and C2H2 are moderately correlated with each other but generally uncorrelated or show only weak correlation with other species. CO is generally uncorrelated with the other measured species possibly because it has the highest volatility and is therefore more susceptible to thermal evolutionary effects. Most of these correlations appear to be independent of dynamical class with a few possible exceptions. Molecular mixing ratios for CH3OH, HCN, C2H6, and CH4 show an expected behavior with heliocentric distance suggesting a dominant ice source, whereas there is emerging evidence that the mixing ratios of NH3, H2CO, C2H2, NH2, and CN may increase at small heliocentric distances, suggesting the possibility of additional sources related to the thermal decomposition of organic dust. Although this provides information on the composition of the most volatile grains in comets, it presents an additional difficulty in classifying comet chemistry because most comets within this dataset were only observed over a limited range of heliocentric distance. Although there is remarkable compositional diversity resulting in a unique chemical fingerprint for each comet, a hierarchical tree cluster analysis is

  1. Infrared Spectra of Water Bending Bands of Propylene Oxide-Water Complexes: Sequential Solvation of a Chiral Molecule in Water

    NASA Astrophysics Data System (ADS)

    Liu, Xunchen; Xu, Yunjie

    2011-06-01

    Sequential solvation of propylene oxide (C3H6O), an prototypical chiral molecule, with water has been investigated using high resolution infrared spectroscopy and ab initio methods. In a number of low resolution studies, the vibrational and vibrational circular dichroism spectral features at the water bending vibration region had been shown to be highly sensitive to the water solvation structures around propylene oxide in aqueous solution. The current study aims to provide quantitative information about solvation of a chiral molecule with water molecules at the molecular level and to provide the experimental benchmarks for calculations of vibrational frequencies in these larger molecular complexes. The high resolution infrared spectra of the propylene oxide-water complexes have been measured using a pulsed jet infrared spectrometer equipped with a room temperature external cavity quantum cascade laser and an astigmatic multi-pass cell. At least 6 bands have been observed from 1650 to 1680 Cm-1. Based on the previous microwave spectroscopic studies, these bands have been assigned to the blue-shifted water bending (ν_2) vibration modes associated with both the syn- and anti- conformers of the binary (C3H6O-H2O) and ternary (C3H6O-(H2O)2) complexes. This report shows the power of high resolution infrared spectroscopy to study multi-conformers of relatively large organic molecule complexes produced in a jet expansion. M. Losada, P. Nguyen, and Y .Xu, J. Phys. Chem. A, 112, 5621, (2008) Z. Su, Q. Wen, and Y. Xu, J. Am. Chem. Soc., 128, 6755, (2006) Z. Su and Y. Xu, Angew. Chem. Int. Ed., 46, 6163, (2007)

  2. New temperature and pressure retrieval algorithm for high-resolution infrared solar occultation spectroscopy: analysis and validation against ACE-FTS and COSMIC

    NASA Astrophysics Data System (ADS)

    Olsen, K. S.; Toon, G. C.; Boone, C. D.; Strong, K.

    2015-10-01

    Motivated by the initial selection of a high-resolution solar occultation Fourier transform spectrometer (FTS) to fly to Mars on the ExoMars Trace Gas Orbiter, we have been developing algorithms for retrieving volume mixing ratio vertical profiles of trace gases, the primary component of which is a new algorithm and software for retrieving vertical profiles of temperature and pressure from the spectra. In contrast to Earth-observing instruments, which can rely on accurate meteorological models, a priori information, and spacecraft position, Mars retrievals require a method with minimal reliance on such data. The temperature and pressure retrieval algorithms developed for this work were evaluated using Earth-observing spectra from the Atmospheric Chemistry Experiment (ACE) FTS, a solar occultation instrument in orbit since 2003, and the basis for the instrument selected for a Mars mission. ACE-FTS makes multiple measurements during an occultation, separated in altitude by 1.5-5 km, and we analyze 10 CO2 vibration-rotation bands at each altitude, each with a different usable altitude range. We describe the algorithms and present results of their application and their comparison to the ACE-FTS data products. The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) provides vertical profiles of temperature up to 40 km with high vertical resolution. Using six satellites and GPS radio occultation, COSMIC's data product has excellent temporal and spatial coverage, allowing us to find coincident measurements with ACE with very tight criteria: less than 1.5 h and 150 km. We present an inter-comparison of temperature profiles retrieved from ACE-FTS using our algorithm, that of the ACE Science Team (v3.5), and from COSMIC. When our retrievals are compared to ACE-FTS v3.5, we find mean differences between -5 and +2 K, and that our retrieved profiles have no seasonal or zonal biases, but do have a warm bias in the stratosphere and a cold bias in the

  3. New temperature and pressure retrieval algorithm for high-resolution infrared solar occultation spectroscopy: analysis and validation against ACE-FTS and COSMIC

    NASA Astrophysics Data System (ADS)

    Olsen, Kevin S.; Toon, Geoffrey C.; Boone, Chris D.; Strong, Kimberly

    2016-03-01

    Motivated by the initial selection of a high-resolution solar occultation Fourier transform spectrometer (FTS) to fly to Mars on the ExoMars Trace Gas Orbiter, we have been developing algorithms for retrieving volume mixing ratio vertical profiles of trace gases, the primary component of which is a new algorithm and software for retrieving vertical profiles of temperature and pressure from the spectra. In contrast to Earth-observing instruments, which can rely on accurate meteorological models, a priori information, and spacecraft position, Mars retrievals require a method with minimal reliance on such data. The temperature and pressure retrieval algorithms developed for this work were evaluated using Earth-observing spectra from the Atmospheric Chemistry Experiment (ACE) FTS, a solar occultation instrument in orbit since 2003, and the basis for the instrument selected for a Mars mission. ACE-FTS makes multiple measurements during an occultation, separated in altitude by 1.5-5 km, and we analyse 10 CO2 vibration-rotation bands at each altitude, each with a different usable altitude range. We describe the algorithms and present results of their application and their comparison to the ACE-FTS data products. The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) provides vertical profiles of temperature up to 40 km with high vertical resolution. Using six satellites and GPS radio occultation, COSMIC's data product has excellent temporal and spatial coverage, allowing us to find coincident measurements with ACE with very tight criteria: less than 1.5 h and 150 km. We present an intercomparison of temperature profiles retrieved from ACE-FTS using our algorithm, that of the ACE Science Team (v3.5), and from COSMIC. When our retrievals are compared to ACE-FTS v3.5, we find mean differences between -5 and +2 K and that our retrieved profiles have no seasonal or zonal biases but do have a warm bias in the stratosphere and a cold bias in the

  4. High-Resolution Infrared Spectrum of BrCN in the ν 2 and ν 1/2ν 2 Regions

    NASA Astrophysics Data System (ADS)

    Bürger, H.; Ma, S.; Demaison, J.; Le Guennec, M.; Degli Esposti, C.; Bizzocchi, L.

    2000-01-01

    FT infrared spectra of BrCN have been recorded in the region of the ν2 band near 340 cm-1, the ν1 band near 580 cm-1, and the 2ν2 band near 690 cm-1 with a resolution between 2.9 and 4.7 × 10-3 cm-1. The vibrational levels (0110), (1000), (0200), (0220), (1110), and (2000) have been analyzed employing cold bands, hot bands, and new millimeter-wave transitions. Band-by-band polynomial analyses and a combined fit of all data relevant to the 2v1 + v2 = 2 polyad levels have been performed. The latter fit considered l-resonance interactions between the (0200), e and (0220), e levels and Fermi resonance between the two Σ states (1000) and (0200). Altogether about 1000 pieces of data up to J = 100 were fitted for each of the two isotopic species with rms of the residuals of 2-8 × 10-4 cm-1 for the infrared and 10-120 kHz for the pure rotational data.

  5. Laboratory Infrared Optical Constants and Reflectance Spectra of Silicon Carbide

    NASA Astrophysics Data System (ADS)

    Pitman, Karly M.; Hofmeister, A. M.; Speck, A. K.

    2006-12-01

    The observed SiC features in astronomical IR spectra of carbon stars (C-stars) correlate with thin-film IR absorption spectra of β-SiC, the polytype most commonly found as presolar grains in meteorites. Comparison between spectra of astronomical sources and laboratory compounds alone is also not sufficient to assess the relative contributions of different minerals to a given observed spectrum: radiative transfer modeling must be performed (cf. Thompson et al. 2006, ApJ, 652, in press). For C-star spectra, radiative transfer modeling is impeded by the lack of trustworthy SiC optical constants for both β and α polytypes. To address the need for improved dust composition parameters, we measured midand far-infrared room temperature reflectance spectra for several polytypes and orientations (E perpendicular to c, E parallel to c) of commercially manufactured SiC: semiconductor grade purity 3C (β-)SiC, several colors of 6H (α-SiC), and synthetic moissanite (α-SiC). The extremely high reflectivity was connected with discrepancies existing among previous absorption laboratory spectra from thin films, crystallites, and powders. We extracted the real and imaginary parts of the complex refractive index (m(λ) = n(λ) + ik(λ)) from these data using classical dispersion analyses [Spitzer et al. 1962] and supplied these results to 1-D radiative transfer models (DUSTY; Ivezic & Elitzur 1995; Nenkova et al. 2000) to determine how the emerging spectrum should change in response to our n(λ) and k(λ) and other dust shell parameters (effective stellar temperature, inner dust shell temperature, optical depth). The results of this work have direct application to carbon-rich AGB stellar outflows, novae, supernovae, and potentially proto-planetary nebulae and may further our understanding of the contribution of SiC to carbon star spectra and the lack of SiC features in the ISM. Work supported by NASA APRA04-000-0041, NSF-AST 0607418, and performed under contract to NASA.

  6. Broad screening and identification of β-agonists in feed and animal body fluid and tissues using ultra-high performance liquid chromatography-quadrupole-orbitrap high resolution mass spectrometry combined with spectra library search.

    PubMed

    Li, Tingting; Cao, Jingjing; Li, Zhen; Wang, Xian; He, Pingli

    2016-02-01

    Broad screening and identification of β-agonists in feed, serum, urine, muscle and liver samples was achieved in a quick and highly sensitive manner using ultra high performance liquid chromatography-quadrupole-orbitrap high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) combined with a spectra library search. Solid-phase extraction technology was employed for sample purification and enrichment. After extraction and purification, the samples were analyzed using a Q-Orbitrap high-resolution mass spectrometer under full-scan and data-dependent MS/MS mode. The acquired mass spectra were compared with an in-house library (compound library and MS/MS mass spectral library) built with TraceFinder Software which contained the M/Z of the precursor ion, chemical formula, retention time, character fragment ions and the entire MS/MS spectra of 32 β-agonist standards. Screening was achieved by comparing 5 key mass spectral results and positive matches were marked. Using the developed method, the identification results from 10 spiked samples and 238 actual samples indicated that only 2% of acquired mass spectra produced false identities. The method validation results showed that the limit of detection ranged from 0.021-3.854 μg kg(-1)and 0.015-1.198 ng mL(-1) for solid and liquid samples, respectively. PMID:26304337

  7. [Raman and infrared spectra of non-stoichiometry uranium oxides].

    PubMed

    Lü, Jun-Bo; Li, Gan; Guo, Shu-Lan

    2014-02-01

    Both of Raman and infrared spectra of seven non-stoichiometry and threestoichiometry uranium oxides, including UO2, U3O7 and UO(2+x) (0spectra of UO(2+x) in the stoichiometry range, U3O7 to U3O8, were first obtained and reported. Three typical peaks were observed at 445, 578 and 1150 cm(-1) in the Raman spectrum of uranium dioxide. The intensities of the peaks at 578 and 1151 cm(-1) decrease quickly with increasing x value of UO(2+x), and while x=0.19, the two peaks disappear. Such peaks can therefore be considered as a fin-gerprint of the quasi-perfect UO2 fluorite structure. The peak at 445 cm(-1) tends to weaken, broaden and shift to higher wavenumber in more oxidised samples. When x=0.32, this peak is shifted to the 459 cm(-1) and a weak peak at about 630 cm(-1) appears. The two new peaks are typical of the tetragonal U3O7. While x> or =0.39, the peak at 459 cm(-1) further splits into separate components. Two peaks at 235 and 754 cm(-1) appear for UO(2.39) and are visible with increased intensity as the oxygen-uranium ratio is increased. And the Raman spectra of UO(2+x) are gradually close to U3O8 in the alpha-phase, which has an orthorhombic unit cell. But several strongest features of the alpha-U3O8 specturm at 333, 397, 483 and 805 cm(-1) are still not outstanding even in UO(2.60). The main feature of the UO2 infrared spectrum shows a very broad and strong adsorption band at 400-570 cm(-1) and another feature is a weak adsorption peak at about 700 cm(-1). The 400-570 cm(-1) band undergoes a progressive splitting into two new peaks at approximately 421 and approximately 515 cm(-1) through increasing incorporation of oxygen into UO2. The weak peak at about 700 cm(-1) disappears and a new weak peak appears at about 645 cm(-1). The three new peaks are the infrared absorption features of U3O7. An absorption peak at 744 cm(-1) which is the strongest feature of alpha-U3O8 infrared spectrum appears for UO(2.39) and is

  8. Near-infrared spectra of the uranian ring system

    NASA Astrophysics Data System (ADS)

    de Kleer, Katherine; de Pater, Imke; Ádámkovics, Máté; Hammel, Heidi

    2013-09-01

    We present the first high-resolution near-infrared (1.18-2.38 μm) spectrum of the rings of Uranus, as observed with adaptive optics on the W.M. Keck II telescope in August 2010. We derive ring equivalent widths, as well as ring and particle reflectivities for the ɛ ring and ringlet groups based on H- and K-band data. We find the rings to be gray, indicating that they are dominated by large particles rather than dust, and we find no evidence for water ice. We present a reflectivity spectrum for the ɛ ring alone, which we also find to be consistent with a flat spectrum. We derive H-band ring particle reflectivities of 0.022 ± 0.010, 0.051 ± 0.009 0.042 ± 0.012, and 0.043 ± 0.001 and K-band ring particle reflectivities of 0.016 ± 0.010, 0.034 ± 0.012, 0.047 ± 0.008 and 0.041 ± 0.002 for the 456, αβ, ηγδ, and ɛ ring groups. Previous observations have found ring particle reflectivities in the 0.033-0.044 range (de Pater, I., Gibbard, S., Macintosh, B.A., Roe, H.G. [2002]. Icarus 160, 359-374; Gibbard, S.G., de Pater, I., Hammel, H.B. [2005]. Icarus 174, 253-262), and are generally consistent with our results.

  9. Copernicus spectra and infrared photometry of 42 Orionis

    NASA Technical Reports Server (NTRS)

    Johnson, H. M.; Snow, T. P., Jr.; Gehrz, R. D.; Hackwell, J. A.

    1977-01-01

    The Orion sword star 42 Ori is embedded in a nebula north of and separated from the Orion nebula. The B1 V star is probably normal. Other members of the multiple remain poorly defined, and the nebula may exhibit some peculiarities that may depend on them. Copernicus ultraviolet spectra of the star are described here, especially in the form of tables of wavelength identifications. The properties of the interstellar material in the line of sight are also discussed. Infrared photometry is presented which suggests that the ratio of total to selective extinction ranges from 3 to 3.5 for the interstellar matter in the direction of 42 Ori. The IR photometry provides no evidence for companion stellar or circumstellar components.

  10. Near infrared photodissociation spectra of the aniline +-argon ionic complexes

    NASA Astrophysics Data System (ADS)

    Pino, T.; Douin, S.; Boudin, N.; Bréchignac, Ph.

    2006-02-01

    The near infrared spectra of the ionic complexes aniline(NH 2) +-argon and aniline(ND 2) +-argon have been measured by laser photodissociation spectroscopy. The bands observed from 10 500 to 13 500 cm -1 have been assigned to the D1(A˜2A2)←D0(X˜2B1) electronic transition within the solvated chromophore. They are characterized by a long vibrational progression involving the 6a mode. On the basis of CASSCF calculations, a large change of geometry along this coordinate is found while the amino group remains in the ring plane. Therefore, a change of the conjugation of the ring rather than a charge transfer is inferred. This is thought to be the origin of the extent of the progression.

  11. Mid infrared spectra of lunar and analog soils

    NASA Technical Reports Server (NTRS)

    Aronson, J. R.; Smith, E. M.

    1978-01-01

    The mid infrared emittance spectrum contains compositional information about lunar soils. In order to be able to properly interpret remotely obtained data, it was necessary to develop a theoretical model of the emittance of particulate minerals. This theory was shown to simulate the spectra of analog lunar soils satisfactorily provided that good values of the optical constants of the component minerals were available. Optical constants have been obtained for dunite, bytownite, augite, ilmenite, and a mare glass analog during this work. Our first measurements on lunar soils indicated that 67711 is very immature (high contrast) and is dominated by feldspar; that 10084 shows very low contrast with some evidence of pyroxene and feldspar bands. 71061 is intermediate between the other two having a gross similarity to 10084 but with considerably more contrast.

  12. Raman and infrared spectra of some tetrahalide crystals

    NASA Astrophysics Data System (ADS)

    Anderson, Anthony; Torrie, Bruce

    1986-03-01

    Recent Raman and infrared spectra of a number of tetrahalide crystals are reported. While some examples of isotopic and crystal field splittings of the internal molecular modes are included, the emphasis is on the external lattice vibrations which are important for investigations of intermolecular forces and lattice dynamics calculations. Because of the weak signals from these non-polar near-spherical molecules and other experimental difficulties, these modes have not been investigated in detail in earlier work. Examples to be discussed include CCl 4, CBr 4 and CF 4, all of which exhibit solid state phase transitions; the tetrachlorides of Ge, Ti, Si and Sn, all of which are thought to have similar crystal structures; and SnBr 4, the structure of which is accurately known and is used as a basis for lattice dynamics calculations.

  13. THE ROLE OF MERGER STAGE ON GALAXY RADIO SPECTRA IN LOCAL INFRARED-BRIGHT STARBURST GALAXIES

    SciTech Connect

    Murphy, Eric J.

    2013-11-01

    An investigation of the steep, high-frequency (i.e., ν ∼ 12 GHz) radio spectra among a sample of 31 local infrared-bright starburst galaxies is carried out in light of their Hubble-Space-Telescope-based merger classifications. Radio data covering as many as 10 individual bands allow for spectral indices to be measured over three frequency bins between 0.15 and 32.5 GHz. Sources having the flattest spectral indices measured at ∼2 and 4 GHz, arising from large free-free optical depths among the densest starbursts, appear to be in ongoing through post-stage mergers. The spectral indices measured at higher frequencies (i.e., ∼12 GHz) are steepest for sources associated with ongoing mergers in which their nuclei are distinct, but share a common stellar envelope and/or exhibit tidal tails. These results hold after excluding potential active galactic nuclei based on their low 6.2 μm polycyclic aromatic hydrocarbon equivalent widths. Consequently, the low-, mid-, and high-frequency spectral indices each appear to be sensitive to the exact merger stage. It is additionally shown that ongoing mergers, whose progenitors are still separated and share a common envelope and/or exhibit tidal tails, also exhibit excess radio emission relative to what is expected given the far-infrared/radio correlation, suggesting that there may be a significant amount of radio emission that is not associated with ongoing star formation. The combination of these observations, along with high-resolution radio morphologies, leads to a picture in which the steep high-frequency radio spectral indices and excess radio emission arise from radio continuum bridges and tidal tails that are not associated with star formation, similar to what is observed for so-called 'taffy' galaxies. This scenario may also explain the seemingly low far-infrared/radio ratios measured for many high-z submillimeter galaxies, a number of which are merger-driven starbursts.

  14. Developing a semi/automated protocol to post-process large volume, High-resolution airborne thermal infrared (TIR) imagery for urban waste heat mapping

    NASA Astrophysics Data System (ADS)

    Rahman, Mir Mustafizur

    In collaboration with The City of Calgary 2011 Sustainability Direction and as part of the HEAT (Heat Energy Assessment Technologies) project, the focus of this research is to develop a semi/automated 'protocol' to post-process large volumes of high-resolution (H-res) airborne thermal infrared (TIR) imagery to enable accurate urban waste heat mapping. HEAT is a free GeoWeb service, designed to help Calgary residents improve their home energy efficiency by visualizing the amount and location of waste heat leaving their homes and communities, as easily as clicking on their house in Google Maps. HEAT metrics are derived from 43 flight lines of TABI-1800 (Thermal Airborne Broadband Imager) data acquired on May 13--14, 2012 at night (11:00 pm--5:00 am) over The City of Calgary, Alberta (˜825 km 2) at a 50 cm spatial resolution and 0.05°C thermal resolution. At present, the only way to generate a large area, high-spatial resolution TIR scene is to acquire separate airborne flight lines and mosaic them together. However, the ambient sensed temperature within, and between flight lines naturally changes during acquisition (due to varying atmospheric and local micro-climate conditions), resulting in mosaicked images with different temperatures for the same scene components (e.g. roads, buildings), and mosaic join-lines arbitrarily bisect many thousands of homes. In combination these effects result in reduced utility and classification accuracy including, poorly defined HEAT Metrics, inaccurate hotspot detection and raw imagery that are difficult to interpret. In an effort to minimize these effects, three new semi/automated post-processing algorithms (the protocol) are described, which are then used to generate a 43 flight line mosaic of TABI-1800 data from which accurate Calgary waste heat maps and HEAT metrics can be generated. These algorithms (presented as four peer-reviewed papers)---are: (a) Thermal Urban Road Normalization (TURN)---used to mitigate the microclimatic

  15. Infrared spectra of small molecular ions trapped in solid neon

    SciTech Connect

    Jacox, Marilyn E.

    2015-01-22

    The infrared spectrum of a molecular ion provides a unique signature for that species, gives information on its structure, and is amenable to remote sensing. It also serves as a comparison standard for refining ab initio calculations. Experiments in this laboratory trap molecular ions in dilute solid solution in neon at 4.2 K in sufficient concentration for observation of their infrared spectra between 450 and 4000 cm{sup !1}. Discharge-excited neon atoms produce cations by photoionization and/or Penning ionization of the parent molecule. The resulting electrons are captured by other molecules, yielding anions which provide for overall charge neutrality of the deposit. Recent observations of ions produced from C{sub 2}H{sub 4} and BF{sub 3} will be discussed. Because of their relatively large possibility of having low-lying excited electronic states, small, symmetric molecular cations are especially vulnerable to breakdown of the Born-Oppenheimer approximation. Some phenomena which can result from this breakdown will be discussed. Ion-molecule reaction rates are sufficiently high that in some systems absorptions of dimer cations and anions are also observed. When H{sub 2} is introduced into the system, the initially-formed ion may react with it. Among the species resulting from such ion-molecule reactions that have recently been studied are O{sub 4}{sup +}, NH{sub 4}{sup +}, HOCO{sup +}, and HCO{sub 2}{sup !}.

  16. Infrared spectra of small molecular ions trapped in solid neon

    NASA Astrophysics Data System (ADS)

    Jacox, Marilyn E.

    2015-01-01

    The infrared spectrum of a molecular ion provides a unique signature for that species, gives information on its structure, and is amenable to remote sensing. It also serves as a comparison standard for refining ab initio calculations. Experiments in this laboratory trap molecular ions in dilute solid solution in neon at 4.2 K in sufficient concentration for observation of their infrared spectra between 450 and 4000 cm!1. Discharge-excited neon atoms produce cations by photoionization and/or Penning ionization of the parent molecule. The resulting electrons are captured by other molecules, yielding anions which provide for overall charge neutrality of the deposit. Recent observations of ions produced from C2H4 and BF3 will be discussed. Because of their relatively large possibility of having low-lying excited electronic states, small, symmetric molecular cations are especially vulnerable to breakdown of the Born-Oppenheimer approximation. Some phenomena which can result from this breakdown will be discussed. Ion-molecule reaction rates are sufficiently high that in some systems absorptions of dimer cations and anions are also observed. When H2 is introduced into the system, the initially-formed ion may react with it. Among the species resulting from such ion-molecule reactions that have recently been studied are O4+, NH4+, HOCO+, and HCO2!.

  17. Theoretical model atmosphere spectra used for the calibration of infrared instruments

    NASA Astrophysics Data System (ADS)

    Decin, L.; Eriksson, K.

    2007-09-01

    Context: One of the key ingredients in establishing the relation between input signal and output flux from a spectrometer is accurate determination of the spectrophotometric calibration. In the case of spectrometers onboard satellites, the accuracy of this part of the calibration pedigree is ultimately linked to the accuracy of the set of reference spectral energy distributions (SEDs) that the spectrophotometric calibration is built on. Aims: In this paper, we deal with the spectrophotometric calibration of infrared (IR) spectrometers onboard satellites in the 2 to 200 μm wavelength range. We aim at comparing the different reference SEDs used for the IR spectrophotometric calibration. The emphasis is on the reference SEDs of stellar standards with spectral type later than A0, with special focus on the theoretical model atmosphere spectra. Methods: Using the MARCS model atmosphere code, spectral reference SEDs were constructed for a set of IR stellar standards (A dwarfs, solar analogs, G9-M0 giants). A detailed error analysis was performed to estimate proper uncertainties on the predicted flux values. Results: It is shown that the uncertainty on the predicted fluxes can be as high as 10%, but in case high-resolution observational optical or near-IR data are available, and IR excess can be excluded, the uncertainty on medium-resolution SEDs can be reduced to 1-2% in the near-IR, to ~3% in the mid-IR, and to ~5% in the far-IR. Moreover, it is argued that theoretical stellar atmosphere spectra are at the moment the best representations for the IR fluxes of cool stellar standards. Conclusions: When aiming at a determination of the spectrophotometric calibration of IR spectrometers better than 3%, effort should be put into constructing an appropriate set of stellar reference SEDs based on theoretical atmosphere spectra for some 15 standard stars with spectral types between A0 V and M0 III.

  18. Modeling near-infrared reflectance spectra of clay and sulfate mixtures and implications for Mars

    NASA Astrophysics Data System (ADS)

    Stack, K. M.; Milliken, R. E.

    2015-04-01

    High-resolution mapping by visible and near-infrared orbital spectrometers has revealed a diversity of hydrated mineral deposits on the surface of Mars. Quantitative analysis of mineral abundances within these deposits has the potential to distinguish depositional and diagenetic processes. Such analysis can also provide important constraints on the nature of putative global and local-scale mineralogical transitions on Mars. However, the ability of models to extract quantitative mineral abundances from spectra of mixtures relevant to sedimentary rocks remains largely untested. This is particularly true for clay and sulfate minerals, which often occur as fine-grained components of terrestrial sedimentary rocks and are known to occur in a number of sedimentary deposits on Mars. This study examines the spectral properties of a suite of mixtures containing the Mg-sulfate epsomite mixed with varying proportions of smectitic clay (saponite, nontronite, and montmorrilonite). The goal of this work is to test the ability of checkerboard (linear) and intimate (non-linear) mixing models to obtain accurate estimates of mineral abundances under ideal and controlled laboratory conditions. The results of this work suggest that: (1) spectra of clay-sulfate mixtures can be reproduced by checkerboard and intimate mixing models to within 2% absolute reflectance or single scattering albedo, (2) clay and epsomite abundance can be modeled to within 5 wt.% when particle diameter is optimized, and (3) the lower threshold for modeling clay in spectra of clay-epsomite mixtures is approximately 10 wt.%, below which the models often fail to recognize the presence of clay.

  19. Stratospheric and mesospheric pressure-temperature profiles from rotational analysis of CO2 lines in atmospheric trace molecule spectroscopy/ATLAS 1 infrared solar occultation spectra

    NASA Technical Reports Server (NTRS)

    Stiller, G. P.; Gunson, M. R.; Lowes, L. L.; Abrams, M. C.; Raper, O. F.; Farmer, C. B.; Zander, R.; Rinsland, C. P.

    1995-01-01

    A simple, classical, and expedient method for the retrieval of atmospheric pressure-temperature profiles has been applied to the high-resolution infrared solar absorption spectra obtained with the atmospheric trace molecule spectroscopy (ATMOS) instrument. The basis for this method is a rotational analysis of retrieved apparent abundances from CO2 rovibrational absorption lines, employing existing constituent concentration retrieval software used in the analysis of data returned by ATMOS. Pressure-temperature profiles derived from spectra acquired during the ATLAS 1 space shuttle mission of March-April 1992 are quantitatively evaluated and compared with climatological and meteorological data as a means of assessing the validity of this approach.

  20. Stratospheric and mesospheric pressure-temperature profiles from rotational analysis of CO2 lines in atmospheric trace molecule spectroscopy/ATLAS 1 infrared solar occultation spectra

    SciTech Connect

    Stiller, G.P.; Gunson, M.R.; Lowes, L.L.; Abrams, M.C.; Raper, O.F.; Farmer, C.B.; Zander, R.; Rinsland, C.P. |||

    1995-02-01

    A simple, classical, and expedient method for the retrieval of atmospheric pressure-temperature profiles has been applied to the high-resolution infrared solar absorption spectra obtained with the atmospheric trace molecule spectroscopy (ATMOS) instrument. The basis for this method is a rotational analysis of retrieved apparent abundances from CO2 rovibrational absorption lines, employing existing constituent concentration retrieval software used in the analysis of data returned by ATMOS. Pressure-temperature profiles derived from spectra acquired during the ATLAS 1 space shuttle mission of March-April 1992 are quantitatively evaluated and compared with climatological and meteorological data as a means of assessing the validity of this approach.

  1. Line shape analysis of two-dimensional infrared spectra

    PubMed Central

    Guo, Qi; Pagano, Philip; Li, Yun-Liang; Kohen, Amnon; Cheatum, Christopher M.

    2015-01-01

    Ultrafast two-dimensional infrared (2D IR) spectroscopy probes femtosecond to picosecond time scale dynamics ranging from solvation to protein motions. The frequency-frequency correlation function (FFCF) is the quantitative measure of the spectral diffusion that reports those dynamics and, within certain approximations, can be extracted directly from 2D IR line shapes. A variety of methods have been developed to extract the FFCF from 2D IR spectra, which, in principle, should give the same FFCF parameters, but the complexity of real experimental systems will affect the results of these analyses differently. Here, we compare five common analysis methods using both simulated and experimental 2D IR spectra to understand the effects of apodization, anharmonicity, phasing errors, and finite signal-to-noise ratios on the results of each of these analyses. Our results show that although all of the methods can, in principle, yield the FFCF under idealized circumstances, under more realistic experimental conditions they behave quite differently, and we find that the centerline slope analysis yields the best compromise between the effects we test and is most robust to the distortions that they cause. PMID:26049447

  2. Infrared Spectra and Optical Constants of Elusive Amorphous Methane

    NASA Technical Reports Server (NTRS)

    Gerakines, Perry A.; Hudson, Reggie L.

    2015-01-01

    New and accurate laboratory results are reported for amorphous methane (CH4) ice near 10 K for the study of the interstellar medium (ISM) and the outer Solar System. Near- and mid-infrared (IR) data, including spectra, band strengths, absorption coefficients, and optical constants, are presented for the first time for this seldom-studied amorphous solid. The apparent IR band strength near 1300 cm(exp -1) (7.69 micrometer) for amorphous CH4 is found to be about 33% higher than the value long used by IR astronomers to convert spectral observations of interstellar CH4 into CH4 abundances. Although CH4 is most likely to be found in an amorphous phase in the ISM, a comparison of results from various laboratory groups shows that the earlier CH4 band strength at 1300 cm(exp -1) (7.69 micrometer) was derived from IR spectra of ices that were either partially or entirely crystalline CH4 Applications of the new amorphous-CH4 results are discussed, and all optical constants are made available in electronic form.

  3. The Infrared Spectra and Absorption Intensities of Amorphous Ices

    NASA Astrophysics Data System (ADS)

    Gerakines, Perry A.; Hudson, Reggie L.; Loeffler, Mark

    2016-06-01

    Our research group is carrying out new IR measurements of icy solids relevant to the outer solar system and to the interstellar medium, with an emphasis on amorphous and crystalline ices below ~ 120 K. Our goal is to update and add to the relatively meager literature on this subject and to provide electronic versions of state-of-the-art data, since the abundances of such molecules cannot be deduced without accurate reference spectra and IR band strengths. In the past year, we have focused on three of the simplest and most abundant components of interstellar and solar-system ices: methane (CH4), carbon dioxide (CO2), and methanol (CH3OH). Infrared spectra from ∼ 4500 to 500 cm-1 have been measured for each of these molecules in μm-thick films at temperatures from 10 to 120 K. All known amorphous and crystalline phases have been reproduced and, for some, presented for the first time. We also report measurements of the index of refraction at 670 nm and the mass densities for each ice phase. Comparisons are made to earlier work where possible. Electronic versions of our new results are available at http://science.gsfc.nasa.gov/691/cosmicice/ constants.html.

  4. Aqueous ammonia and ammonium chloride hydrates: Principal infrared spectra

    NASA Astrophysics Data System (ADS)

    Max, Jean-Joseph; Chapados, Camille

    2013-08-01

    The infrared (IR) spectra of aqueous ammonia (NH3) and aqueous ammonium chloride (NH4Cl) were recorded by attenuated total reflectance to obtain their molecular organizations. Factor analysis (FA) of the spectra revealed two hydrates for each species: (NH3)2ṡH2O and NH3ṡ3H2O; NH·HO; and (NH4+,Cl)·3HO, respectively. The hydrate spectra and species abundances were obtained as a function of total concentrations. From this the equilibrium equation between the two ammonia hydrates was determined: 2[(NH)2·HO]+5(HO)2⇌4[NH·3HO] with its equilibrium constant Kα = (2.3 ± 0.6) × 10-5 L3 mol-3. Similarly, for the two ammonium chloride hydrates the equation is 2[(NHCl)2·HO]+5(HO)2⇌4[NHCl·3HO] with its equilibrium constant: Kβ = (4 ± 1) × 10-7 L3 mol-3. Band simulations of the hydrate spectra were compared to that of pure liquid water and parent molecules. For aqueous ammonium chloride solutions the water and all ammonium hydrate bands are slightly displaced from that of pure water and pure ammonium chloride, respectively. However, for ammonia hydrates the situation is different: compared to the gas situation the hydrate water bands have similar displacements as that of pure liquid water; the ammonia deformation bands are also little displaced but the stretching bands are strongly red shifted. These shifts, which are even greater than that in pure liquid water, are attributed to strong hydrogen bonding situations: water-H with N-ammonia and ammonia-H with O-water. This explains the high solubility of ammonia in water. The comparison between the spectra of aqueous ammonium chloride and ammonia hydrates indicates that ammonium ion is not present in aqueous ammonia from 11.3 M down to at least our detection limit of 3 mM NH3.

  5. Analysis of fingerprints features of infrared spectra of various processed products of Rhizoma Coptidis and their different extracts

    NASA Astrophysics Data System (ADS)

    Xu, Beilei; Zhang, Guijun; Xu, Changhua; Sun, Suqin

    2015-09-01

    Fourier transform infrared spectroscopy (FT-IR) associated with second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2D-IR) are employed to analyze various processed products and different extracts of Rhizoma Coptidis. There is a shift of the peak of 1641 cm-1 of raw Rhizoma Coptidis after processed, which drifts to lower wave number. Peaks at 1508, 1387, 1363, 1332, 1274 and 1234 cm-1 barely change in most samples, except an obvious enhancement of these peaks after processed, suggesting that processed Rhizoma Coptidis may have higher content of berberine than raw material, which is corresponding to the results of correlation coefficients analysis. There are some differences in the absorption peaks in the range of 1800-1000 cm-1 in the SD-IR spectra, which have better resolution, of different processed products. 2D-IR spectra, which elevate the resolution further, can present more differences among the products in the range of 1300-800 cm-1 and 1800-1300 cm-1. Analysis of aqueous, ethanol and petroleum ether extracts of various processed products proves that there are distinctive differences of all auto-peaks in shapes and intensities in all of them. With the advantages of high resolution, high speed and convenience, FT-IR combined with 2D-IR can quickly and precisely distinguish various processed products of Rhizoma Coptidis and can be applied to predict the tendency of transformation of the complicated chemical mixture systems under heat perturbation.

  6. Near-Infrared Spectra of Chamaeleon I Stars

    NASA Astrophysics Data System (ADS)

    Gómez, M.; Mardones, D.

    2003-04-01

    We present low-resolution (R~500) near-infrared spectra of 46 candidate young stellar objects in the Chamaeleon I star-forming region recently detected in several deep photometric surveys of the cloud. Most of these stars have K<12. In addition, we present spectra of 63 previously known southern hemisphere young stars mainly belonging to the Chamaeleon I and Lupus dark clouds. We describe near-infrared spectroscopic characteristics of these stars and use the water vapor indexes to derive spectral types for the new objects. Photometric data from the literature are used to estimate the bolometric luminosities of all sources. We apply the pre-main-sequence evolutionary tracks and isochrones of D'Antona & Mazzitelli to derive masses and ages. We detect two objects with mass below the H-burning limit among the 46 new candidates. One of these objects (PMK99 IR Cha INa1) is the likely driving source of a bipolar outflow in the northern region of the cloud. Combining our targets with previously known members of the cloud we analyze the mass and age distributions for 145 stars in the Chamaeleon I dark could. The mass histogram rises from about 2.5 up to 0.4 Msolar and then falls off. The median mass is 0.30 Msolar. The current population with masses greater than 0.4 Msolar is essentially complete. The scarcity of very low mass members is interpreted as population bias toward the least massive and fainter objects. If we assume the true Chamaeleon I initial mass function is flat (in logarithmic mass bins) in the interval 0.4-0.04 Msolar as recently found by Comerón et al. in the central 300 arcmin2 region, then we estimate that ~100 stars remain to be found in that mass range. The distribution of ages indicates an active star-formation episode within the last ~5×105 yr and a decreasing rate at older ages (a few times 107 yr). Based on observations collected at the European Southern Observatory, Chile, (ESO proposal N.63.I-0269[A]).

  7. High-resolution measurements of the K-alpha spectra of low-ionizationm species of iron: A new spectral signature of nonequilibrium ionization conditions in young supernova remnants

    NASA Technical Reports Server (NTRS)

    Decaux, V.; Beiersdorfer, P.; Osterheld, A.; Chen, M.; Kahn, S. M.

    1995-01-01

    We present the first systematic laboratory measurements of high-resolution K-alpha spectra of intermediate ions of iron, Fe X-XVII. These lines are not produced in collisional equilibrium plasmas because of the relevant charge states cannot exist at the high electron temperatures required for appreciable excitation of the K-alpha transitions. However, they can provide excellent spectral diagnostics for nonequilibrium ionization conditions, such the ionizing plasmas of young supernova remnants. To facilitate the line identifications, we compare our spectra with theoretical atomic calculations performed using multiconfiguration parametric potential and Dirac-Fock atomic codes. Our measurements also allow direct comparison with time-dependent ionization balance calculations for ionizing plasmas, and good agreement is found.

  8. Infrared Spectra and Optical Constants of Acetylene and Ethane Ices

    NASA Astrophysics Data System (ADS)

    Moore, Marla H.; Ferrante, R. F.; Hudson, R. L.; Moore, W. J.

    2012-10-01

    Hydrocarbon-containing ices have characteristic absorption bands in both the mid- and near-infrared spectral regions, yet accurate optical constants are not available for most of these molecules. Ices with a hydrocarbon component have been identified on several TNOs (1) and the presence of volatiles, such as hydrocarbons, is inferred for intermediate or large TNOs based on sublimation models (2, 3). In our laboratory we recently have undertaken low-temperature spectroscopic studies of C2 hydrocarbons. We report IR spectra for acetylene (C2H2) and ethane (C2H6) ice in both the amorphous and crystalline phases at multiple temperatures. We include measurements of the refractive index at 670 nm for both the amorphous and crystalline phases of each ice. The optical constants, the real (n) and imaginary (k) components of the complex index of refraction, were determined from 7000 - 400 cm-1 (1.4 - 25 microns) at multiple temperatures using a Kramers-Kronig analysis. A goal of the present work is to provide a data base of optical constants of C2 molecules similar to that of Hudgins et al. (4) and Moore et al. (5). These values, as well as our calculated individual band strengths, will have great practical importance for the ongoing analysis of TNO spectra. (1) Brown, M.E. et al., Astron J., 133, 284, 2007. (2) Delsanti, A. et al., A&A, 52, A40, 2010. (3) Schaller, E. L. & Brown, M. E., ApJ, 659, L61, 2007. (4) Hudgins, D. M. et al., ApJS, 86, 713, 1993. (5) Moore, M. H. et al., ApJS, 191, 96, 2010. Thi