Relaxation rates of lower laser levels in CO2

The temporal decay of the laser pulse which occurs in the afterglow of a pulsed discharge in pure CO2 is shown to be controlled by the decay of the lower laser level. By varying the CO2 pressure, the relaxation rate of the 02°0 level was found to be ∼ 1.3 × 106/Torr sec. The 10°0 level was found to be governed by two decay rates: a fast rate, ∼ 1.7 × 106/Torr sec, and a slow rate, ∼ 1.7 × 105/Torr sec. These rates were unaffected by the presence of He and are attributed to the V–V equilibration processes within the ν1 and ν2 mode of CO2.