Experimental studies of collision effects on the saturation characteristics of vibration-rotation transitions for 00°1-10°0 band of CO2 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 CO2• Vibration-rotation transitions, at pressures greater than or equal to 1 mm Hg, 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°1-10°0 by added gases have been obtained, which at t = 8000K appeared to be O-C02-Hc = 6 × 10-19; σC02-Ne = 2.8 × 10-18; σC02-CO? = 6.6 X 10-18; σC02-N2= 1.2 X 10–17 cm2. 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. Copyright © 1969 by The Institute of Electrical and Electronics Engineers, Inc.
