Characteristics of the ionization of the active medium of a TEA CO2 laser by high-power picosecond infrared radiation pulses

A numerical analysis was made of a model of transient ionization of the gaseous medium of a TEA CO₂ laser exposed to high-power picosecond infrared radiation pulses. The dynamics of changes in the electron energy distribution during a pulse were studied. The electron avalanche evolution constants for exposure to infrared pulses of varying duration and energy were determined for gas mixtures of varying composition. The conditions of validity of simplified models of electron impact ionization were substantiated. Criteria subject to which the avalanche evolution constant can be considered to be a single-valued function of the instantaneous radiation intensity were determined.