Collision effect on the saturation character of vibration-rotation transitions for 00°1-10°0 band of CO2

Experimental studies of collision effects on the saturation characteristics of vibration-rotation transitions for
00\deg1-10\deg
0 band of CO
2
is described. Saturation was studied in a passive absorption cell inside the laser resonator. The saturation value could be altered by varying the cell temperature and the pressure of CO
2
. Vibration-rotation transitions, at pressures greater than or equal to 1 mmHg, were found to be saturated homogeneously, in spite of the fact that the Lorenz width was much less than the Doppler width. This is explained by the high number of collisions during the lifetime in a vibrational state. In this case the spectrum of a single molecule corresponds to that of a Doppler profile. Cross sections for the destruction of levels of
00\deg1-10\deg0
by added gases have been obtained, which at
t = 800\deg
K appeared to be σCO
2
-He =
6 \times 10^{-19};\sigma
CO
2
-Ne =
2.8 \times 10^{-18}; \sigma
CO
2
-CO
2
=
6.6 \times 10^{-18}; \sigma
CO
2
-N
2
=
1.2 \times 10^{-17}
cm
²
The introduction of sufficiently large absorption caused self-sustained radiation pulsation. When the field influenced the saturating system for only a short period of time, with the interaction time being commensurate with the period of time between collisions, the line was saturated nonhomogeneously. This was expressed by the fact that with the scanning of the laser frequency, a peak power output was observed, corresponding to Lamb's hole, in the center of a saturation line.