Collisional Broadening of Vibrational-Rotational CO2 Lines by Buffer Gases

• Published in: Atmospheric and oceanic optics 2020-05, Vol.33 (3), p.229-237
• Main Authors: Arshinov, K. I., Krapivnaya, O. N., Nevdakh, V. V., Shut, V. N.
• Format: Article
• Language: English
• Subjects: Absorptivity; Binary mixtures; Buffers; Carbon dioxide; Carbon dioxide lasers; Coefficients; Collisional broadening; Electric moments; Gases; Lasers; Line spectra; Mathematical analysis; Nitrous oxide; Optical Devices; Optics; Photonics; Physics; Physics and Astronomy; Rare gases; Spectroscopy of Ambient Medium; Temperature; Triatomic molecules; Tunable lasers
• ISSN: 1024-8560; 2070-0393
• DOI: 10.1134/S1024856020030033

Unsaturated absorption coefficients in pure CO 2 and binary mixtures of CO 2 with buffer gases M j  (He, Ar, Kr, Xe, N 2 , O 2 , CO, N 2 O, 13 C 16 O 2 ) were measured with a tunable CO 2 laser at the central frequencies of the R (8), R (22), R (34), P (8), P (22), and P (36) CO 2 spectral lines of the 10 0 0–00 0 1 transition at a temperature of 300–700 K. A technique is described and the coefficients of self-broadening and broadening of CO 2 spectral lines by a buffer gas M j are calculated. It is shown that the efficiency of the CO 2 interaction with diatomic and triatomic molecules is determined by the electric moment; in the case of inert gases, the mass factor plays the major role. It is ascertained that the temperature dependences of the collisional broadening of CO 2  spectral lines can be highly accurately approximated by power functions with two different exponents.