Excitation dependence of the bending mode temperature in pulsed TE CO2 lasers

The observation of “steps” which appear in the gain immediately after excitation in pulsed TE CO₂ discharges is reported. It is shown that the measurement of the step size relative to the peak gain serves to determine the population of the lower laser level and thereby, the initial vibrational temperature (T₁) of the bending mode. This technique is applied to a study of T₁ as a function of the discharge input energy.