Optical gain optimization in a supersonic stream when vibrationally excited $N_2$ is mixed with $CO_2-He$

Using a quasione-dimensional model, an optimization was made of the optical gain in a supersonic flow when a stream of $N_2$ cooled under the nonequilibrium conditions is mixed with a $CO_2-He$ stream. The simplex method was used to perform a multiparameter optimization with respect to the gas composition, initial parameters of the intermixing streams, and parameters defining the shape of the nozzle. It was found that the highest gain values are achieved close to the disruption boundary of the supersonic flow. The highest gain was $8,92\cdot10^{-2}$ cm${}^{-1}$.