The Experts below are selected from a list of 27429 Experts worldwide ranked by ideXlab platform
R Volkamer - One of the best experts on this subject based on the ideXlab platform.
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Rayleigh Scattering cross section measurements of nitrogen argon oxygen and air
Journal of Quantitative Spectroscopy & Radiative Transfer, 2014Co-Authors: Ryan Thalman, Kyle J Zarzana, R Volkamer, Margaret A. TolbertAbstract:Abstract Knowledge about Rayleigh Scattering cross sections is relevant to predictions about radiative transfer in the atmosphere, and needed to calibrate the reflectivity of mirrors that are used in high-finesse optical cavities to measure atmospheric trace gases and aerosols. In this work we have measured the absolute Rayleigh Scattering cross-section of nitrogen at 405.8 and 532.2 nm using cavity ring-down spectroscopy (CRDS). Further, multi-spectral measurements of the Scattering cross-sections of argon, oxygen and air are presented relative to that of nitrogen from 350 to 660 nm using Broadband Cavity Enhanced Spectroscopy (BBCES). The reported measurements agree with refractive index based theory within 0.2±0.4%, and have an absolute accuracy of better than 1.3%. Our measurements expand the spectral range over which Rayleigh Scattering cross section measurements of argon, oxygen and air are available at near-ultraviolet wavelengths. The expressions used to represent the Rayleigh Scattering cross-section in the literature are evaluated to assess how uncertainties affect quantities measured by cavity enhanced absorption spectroscopic (CEAS) techniques. We conclude that Rayleigh Scattering cross sections calculated from theory provide accurate data within very low error bounds, and are suited well to calibrate CEAS measurements of atmospheric trace gases and aerosols.
Ryan Thalman - One of the best experts on this subject based on the ideXlab platform.
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Rayleigh Scattering cross section measurements of nitrogen argon oxygen and air
Journal of Quantitative Spectroscopy & Radiative Transfer, 2014Co-Authors: Ryan Thalman, Kyle J Zarzana, R Volkamer, Margaret A. TolbertAbstract:Abstract Knowledge about Rayleigh Scattering cross sections is relevant to predictions about radiative transfer in the atmosphere, and needed to calibrate the reflectivity of mirrors that are used in high-finesse optical cavities to measure atmospheric trace gases and aerosols. In this work we have measured the absolute Rayleigh Scattering cross-section of nitrogen at 405.8 and 532.2 nm using cavity ring-down spectroscopy (CRDS). Further, multi-spectral measurements of the Scattering cross-sections of argon, oxygen and air are presented relative to that of nitrogen from 350 to 660 nm using Broadband Cavity Enhanced Spectroscopy (BBCES). The reported measurements agree with refractive index based theory within 0.2±0.4%, and have an absolute accuracy of better than 1.3%. Our measurements expand the spectral range over which Rayleigh Scattering cross section measurements of argon, oxygen and air are available at near-ultraviolet wavelengths. The expressions used to represent the Rayleigh Scattering cross-section in the literature are evaluated to assess how uncertainties affect quantities measured by cavity enhanced absorption spectroscopic (CEAS) techniques. We conclude that Rayleigh Scattering cross sections calculated from theory provide accurate data within very low error bounds, and are suited well to calibrate CEAS measurements of atmospheric trace gases and aerosols.
W. Yao - One of the best experts on this subject based on the ideXlab platform.
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Rayleigh Scattering in rare-gas liquids
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2002Co-Authors: George M. Seidel, R. E. Lanou, W. YaoAbstract:Abstract The Rayleigh Scattering length has been calculated for rare-gas liquids in the ultraviolet for the frequencies at which they luminesce. The calculations are based on the measured dielectric constants in the UV in the gas phase, in some cases extrapolated to the wavelength of luminescence. The Scattering length may place constraints on the design of some large-scale detectors, using UV luminescence, being proposed to observe solar neutrinos and dark matter. Rayleigh Scattering in mixtures of rare-gas liquids is also discussed.
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Rayleigh Scattering in rare-gas liquids
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2002Co-Authors: George M. Seidel, R. E. Lanou, W. YaoAbstract:The Rayleigh Scattering length has been calculated for rare-gas liquids in the ultraviolet for the frequencies at which they luminesce. The calculations are based on the measured dielectric constants in the gas phase, except in the case of xenon for which measurements are available in the liquid. The Scattering length mayplace constraints on the design of some large-scale detectors, using uv luminescence, being proposed to observe solar neutrinos and dark matter. Rayleigh Scattering in mixtures of rare-gas mixtures is also discussed.Comment: 8 pages, 4 tables; This version corrects erratum in table and has expanded discussion in Section II. Accepred for publication in NIM
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Rayleigh Scattering in rare gas liquids
arXiv: High Energy Physics - Experiment, 2001Co-Authors: George M. Seidel, R. E. Lanou, W. YaoAbstract:The Rayleigh Scattering length has been calculated for rare-gas liquids in the ultraviolet for the frequencies at which they luminesce. The calculations are based on the measured dielectric constants in the gas phase, except in the case of xenon for which measurements are available in the liquid. The Scattering length mayplace constraints on the design of some large-scale detectors, using uv luminescence, being proposed to observe solar neutrinos and dark matter. Rayleigh Scattering in mixtures of rare-gas mixtures is also discussed.
Wim Ubachs - One of the best experts on this subject based on the ideXlab platform.
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Deep-UV Rayleigh Scattering of N2, CH4 and SF6
Molecular Physics, 2008Co-Authors: Dmitry Ityaksov, Harold Linnartz, Wim UbachsAbstract:Rayleigh Scattering room temperature cross-section values of N2, CH4 and SF6 have been obtained between 198 and 270 nm by combining cavity ring-down spectroscopy (CRDS) and pressure ramp measurements. The experimental data have been fitted to a functional representation, describing the ~1/λ4 like behavior of the Rayleigh Scattering cross section over a wide wavelength range. The resulting values are compared to numerical predictions, based on refractive indices and molecular anisotropy data as available from literature. From this, values of molecular volume polarizability αvol and depolarization ratios are derived. It is found that the optical extinction for all three gases is governed by Rayleigh Scattering for wavelengths down to 200 nm. No absorption onsets in the specified deep-UV region have been observed.
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Deep-UV Rayleigh Scattering of N2, CH4 and SF6
Molecular Physics, 2008Co-Authors: Dmitry Ityaksov, Harold Linnartz, Wim UbachsAbstract:Rayleigh Scattering room temperature cross-section values of N2, CH4 and SF6 have been obtained between 198 and 270 nm by combining cavity ring-down spectroscopy (CRDS) and pressure ramp measurements. The experimental data have been fitted to a functional representation, describing the ∼1/λ4 like behaviour of the Rayleigh Scattering cross section over a wide wavelength range. The resulting values are compared with numerical predictions, based on refractive indices and molecular anisotropy data available in the literature. From this, values of molecular volume polarizability αvol and depolarization ratios are derived. It is found that the optical extinction for all three gases is governed by Rayleigh Scattering for wavelengths down to 200 nm. No absorption onsets in the specified deep-UV region have been observed.
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Experimental verification of Rayleigh Scattering cross sections
Optics Letters, 2000Co-Authors: H. Naus, Wim UbachsAbstract:The cavity-ringdown technique is applied to measure Rayleigh extinctions of Ar, N2, and SF6 in the 560–650-nm region at 294 K. It is shown that experimental and calculated Rayleigh Scattering cross sections agree within an experimental uncertainty of 1% (for SF6, 3%).
Margaret A. Tolbert - One of the best experts on this subject based on the ideXlab platform.
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Rayleigh Scattering cross section measurements of nitrogen argon oxygen and air
Journal of Quantitative Spectroscopy & Radiative Transfer, 2014Co-Authors: Ryan Thalman, Kyle J Zarzana, R Volkamer, Margaret A. TolbertAbstract:Abstract Knowledge about Rayleigh Scattering cross sections is relevant to predictions about radiative transfer in the atmosphere, and needed to calibrate the reflectivity of mirrors that are used in high-finesse optical cavities to measure atmospheric trace gases and aerosols. In this work we have measured the absolute Rayleigh Scattering cross-section of nitrogen at 405.8 and 532.2 nm using cavity ring-down spectroscopy (CRDS). Further, multi-spectral measurements of the Scattering cross-sections of argon, oxygen and air are presented relative to that of nitrogen from 350 to 660 nm using Broadband Cavity Enhanced Spectroscopy (BBCES). The reported measurements agree with refractive index based theory within 0.2±0.4%, and have an absolute accuracy of better than 1.3%. Our measurements expand the spectral range over which Rayleigh Scattering cross section measurements of argon, oxygen and air are available at near-ultraviolet wavelengths. The expressions used to represent the Rayleigh Scattering cross-section in the literature are evaluated to assess how uncertainties affect quantities measured by cavity enhanced absorption spectroscopic (CEAS) techniques. We conclude that Rayleigh Scattering cross sections calculated from theory provide accurate data within very low error bounds, and are suited well to calibrate CEAS measurements of atmospheric trace gases and aerosols.
