Spectral Line Profiles in the 4.3 Micron Band of Carbon Dioxide

Accurate computation of atmospheric transmission requires the complete description of both the atmospheric path, in terms of the thermodynamic conditions, and of the spectroscopic properties of all optically active elements in the path. One of the major sources of extinction in the infrared spectral region is absorption by CO2. It has been known for many years now that the spectral line profiles for CO2 are significantly non-Lorentzian and this paper describes a method for obtaining the true line profiles from experiment and presents results for CO2 spectral lines in the 4.3 micron band.