Population inversion in a gas mixture stream containing carbon dioxide and expanding through a slit

A calculation is made of the kinetics of the vibrational relaxation in CO₂+H₂O+N₂ and CO₂+He+N₂ mixtures during their flow from a slit into vacuum. Allowance is made for the most important energy exchange mechanisms vibration-vibrational and vibration-translational processes. The dynamics of a nonequilibrium gas is considered in the approximation of an adiabatic motion of a medium with an effective adiabatic exponent (ratio of the specific heats) corresponding to a particular degree of "freezing" of the vibrational component of the specific heat of the gas. A comparison is made of the calculated values of the gain with the experimental results.