Knowledge Bank

Radiation from carbon dioxide laser emitting the P(22) line of the $960cm-1$ band has been passed through a one-meter multiple pass absorption cell for which geometrical path lengths up to 56 meters are attainable. Transmittances of pure $CO2$ samples and mixtures of $CO2$ with a broadening gas were compared for samples having the same absorber thickness; the results allow the determination of the self-broadening coefficient of $CO2$ relative to the broadening gas. Self-broadening coefficients and ratios of optical collision diameters will be presented and compared with results of other workers. J. A. Gardner is now with the Jet Propulsion Laboratory, Pasadena, California.