CO₂ pressure broadening and shift coefficients for the 2-0 band of ¹²C¹⁶O

Abstract

Fourier transform absorption spectra of the 2-0 band of ¹²C¹⁶O mixed with CO₂ have been recorded at total pressures from 156 to 1212 hPa and at 4 different temperatures between 240 K and 283 K. CO₂ pressure-induced line broadening and line shift coefficients, and the temperature dependence of the former have been measured including line mixing using a multi-spectrum non-linear least squares fitting technique. Different line shape models have been considered to take into account the Dicke narrowing or speed dependence effects. Measured line-shape parameters were compared with theoretical values, calculated for individual temperatures using a semi-empirical method and the Exponential Power Gap (EPG) law.