Accurate modeling of the diagnostic 118-GHz oxygen line for remote sensing of the atmosphere. (July 2017)

• Record Type: Journal Article
• Authors: Koshelev, M.A.; Delahaye, T.; Serov, E.A.; Vilkov, I.N.; Boulet, C.; Tretyakov, M.Yu.
• Is Part Of: Journal of quantitative spectroscopy & radiative transfer. Volume 196(2017)
• Page Start: 78
• Page End: 86
• Publication Date: 2017-07
• Subjects: oxygen -- fine structure lines -- collision relaxation -- pressure broadening -- speed dependence -- line mixing -- atmospheric applications; Spectrum analysis -- Periodicals; Radiation -- Periodicals; Analyse spectrale -- Périodiques; Rayonnement -- Périodiques; Radiation; Spectrum analysis; Periodicals; 543.0858
• DOI: 10.1016/j.jqsrt.2017.03.043
• Languages: English
• ISSNs: 0022-4073

Abstract

Abstract: We report the results of laboratory investigations of the shape of the diagnostic atmospheric N = 1- oxygen line performed over a very wide range of pressures from 0.4 to 1000 Torr using two principally different spectrometers having complementary abilities. A spectrometer with a radio-acoustic detector of absorption was used for recording low pressure spectra spanning the 0.4–2 Torr range, and high pressure data from 250 to 1000 Torr were registered by a resonator spectrometer. The sensitivity of both instruments was improved significantly which allowed us to obtain signal-to-noise ratio at spectra recordings of the order of a few thousands. The spectra analysis enabled the first manifestation of the speed-dependence of the collision cross section of the line, along with considerable refinement of other parameters, including pressure broadening, intensity and line-mixing. The results are of primary importance for atmospheric applications. Highlights: Outstanding SNR is achieved for the 118-GHz diagnostic line recordings in the 0.4-1000 Torr pressure range. Clear manifestation of the SD effect was observed for this line. A new line shape model was developed for taking into account SD and mixing effects. Most accurate line shape parameters were retrieved for atmospheric applications.