Kinetic theory of CO chemical lasers

A computer model coupling one-dimensional descriptions of reaction kinetics, V-V and V-T energy transfer, stimulated emission and nonequilibrimn gas dynamics, which has been developed to characterize chemically pumped CO laser media, is described. Theoretical predictions of such parameters as small-signal gain coefficient and specific laser power are presented for the CW CO lasing system chemically pumped by the bimolecular exchange reactions O + CS2→ CS + SO O + CS → CO* + S. The species compositions and state populations of the laser emitters are characterized by a set of rate equations that include anharmonic effects where appropriate. Classical one-dimensional conservation equations are used to evaluate the thermodynamic state functions of the flow. The model assumes a transverse Fabry-Perot cavity to evaluate laser emission on multiple cascading, vibrational-rotational transitions. Gain coefficient computations include the effects of self- and foreign-gas broadening. Results of a parametric study which explicitly identifies the influence of key variables on CO laser characteristics-specific output power and small signal gain coefficients-are presented.