Broadening parameters of the H2O–He collisional system for astrophysical applications

• DOI: 10.1016/j.jms.2016.01.009
• Publication Date: 2016-01-23T02:45:16Z
• Authors: T.M. Petrova; A.M. Solodov; A.A. Solodov; V.I. Starikov
• Keywords: Line (geometry); Spectral resolution

Abstract The water vapor line broadening γ and shift δ coefficients in the ν 1 + ν 2 , ν 2 + ν 3 , ν 1 + ν 3 , 2ν 3 , 2ν 1 , 2ν 2 + ν 3 , and ν 1 + 2ν 2 vibrational bands were obtained from the analysis of the H 2 O–He absorption spectra, recorded in the region from 5000 to 7500 cm −1 with the spectral resolution of 0.01 cm −1 using a Bruker IFS 125HR FTIR spectrometer. The vibrational bands 2ν 3 and ν 1 + 2ν 2 were investigated for the first time. The calculations of γ and δ were performed in the framework of the semi-classical method. The rotational contributions as well as the contributions connected with the accidental resonances were taken into account in the used H 2 O–He interaction potential. The analytical representation of the broadening coefficients γ at planetary temperatures was introduced and discussed.