Measurements of the temperature variation of the resonant absorption coefficient in shock heated CO2 gas (350–1600 K) using a laser source operating on the P(20) or P(18) transition are reported. Values obtained are compared with theory allowing for mixed mode contributions to absorption as well as dependence of the optical broadening cross section on temperature.
A. R. Strilchuk and A. A. Offenberger, "High Temperature Absorption in CO2 at 10.6 µm," Appl. Opt. 13, 2643-2646 (1974)