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J. Chem. Phys. 148, 244302 (2018);, 244302© 2018 Author(s).Fourier-transform-spectroscopicphotoabsorption cross sections andoscillator strengths for theS2 B 3..u..X 3..g system



G. Stark, H. Herde, J. R. Lyons, A. N. Heays, N. Oliveira, Gillian Nave, B. R. Lewis, S. T. Gibson


Photoabsorption cross sections and oscillator strengths for the strong, predissociating vibrational bands, v 11, in the S2 B 3..u .. X 3..g (v; 0) system are reported. Absorption measurements were undertaken of S2 vapor in a radio-frequency discharge through H2S seeded in helium and in a two-temperature sulfur furnace at temperatures of 37010 K and 82310 K, respectively. S2 column densities were determined in each source by combining experimental line strengths in low-v non-predissociating B ..X bands (v < 7) with calculated line f-values based on measured radiative lifetimes and calculated branching ratios. The broad-band capabilities of two vacuum-ultraviolet Fourier-transform spectrometers, used with instrumental resolutions of 0.22 cm..1 and 0.12 cm..1, allowed for simultaneous recordings of both non-predissociating and predissociating bands, thus placing the predissociating-band cross sections on a common absolute scale. Uncertainties in the nal cross-section datasets are estimated to be 15% for the 370-K vapor and 10% for the 823-K vapor. The experimental cross sections are used to inform a detailed predissociation model of the B(v) levels in an accompanying paper (following paper, this issue). For astrophysical and other applications, this model can be adjusted simply to provide isotopologue-speci c cross sections for a range of relevant temperatures.
Journal of Chemical Physics


Molecular spectra, ultraviolet spectra, vibrational analysis, Fourier transform spectroscopy, Absorption spectroscopy


Stark, G. , Herde, H. , Lyons, J. , Heays, A. , Oliveira, N. , Nave, G. , Lewis, B. and Gibson, S. (2018), J. Chem. Phys. 148, 244302 (2018);, 244302&#169; 2018 Author(s).Fourier-transform-spectroscopicphotoabsorption cross sections andoscillator strengths for theS2 B 3&#6;..u..X 3&#6;..g system, Journal of Chemical Physics, [online],, (Accessed May 29, 2023)
Created June 25, 2018, Updated October 12, 2021