Possibility of building a gasdynamic laser utilizing transitions between levels of paired CO2 modes

Calculations of the vibrational relaxation kinetics of carbon dioxide in a CO₂–Ar mixture expanding through a slit into a vacuum are used to evaluate the feasibility of using gasdynamic thermal pumping to obtain lasing between the levels of paired CO₂ modes. It is shown that the gain due to the (03¹0)–(100) transition in CO₂ may reach 0.1 cm^–1 and, at the optimal heating tempertures for a CO₂:Ar =1:1 mixture (T_i≈1500 °K), the thermal energy conversion efficiency in the gasdynamic laser may be 12%.