Ionization and Recombination Kinetics in a Plasma Accelerator Channel

A number of theoretical approaches to the investigation of ionizing gas flows are analyzed and compared with reference to a plasma accelerator channel. The transition from a weakly ionized gas to a plasma is considered within the framework of the complete system of equations. The ionizing gas flow model is based on the magnetogasdynamic equations of a continuum and the equation of ionization and recombination kinetics. The corresponding coefficients are determined both within the framework of the standard theory and within a modified diffusion approximation, including possible variations. In addition, for comparison purposes some results of numerical experiments on the ionization process under conditions of local thermodynamic equilibrium are given.