HIGH-TEMPERATURE ABSORPTION IN THE 10.4-MU-M BAND OF CO2

The absorption coefficient of pure CO2 has been measured as a function of temperature in the 295–650 K range for the P(14)–P(24) and R(10)–R(24) laser transitions. Cubic curves fitted to the experimental results are given to allow interpolation at all temperatures within the range. The P(20) transition shows an anomolously high value of absorption. Variation of absorption coefficient with pressure was linear but small for all transitions in the 200–700-Torr pressure range at three temperatures. Calculations of the absorption coefficient are performed and compared with experimental data. © 1979 Optical Society of America.