Simulation of the positive column of a glow discharge in an inert gas-chorine mixture with allowance for the dissociation of chlorine molecules

The model of the positive column (PC) of a moderate-pressure (5–30 Torr) glow discharge in a mixture of inert gases and chlorine under currents of up to 50 mA/cm$^2$ extends the existing models of discharges in electronegative gases. The novelty of the model is the inclusion of radial nonuniformity in the gas temperature and dissociation of chlorine molecules into atoms, as well as allowance for heating of ions by the electric field and step ionization. As a result, the calculated radial profiles of charged particle concentrations are not only in qualitative agreement with earlier-developed theories of electronegative discharges, but also in quantitative agreement with experimental data. It is shown that allowance for dissociation of chlorine molecules and the effect of longitudinal field $E_z$ on the ion temperatures is essential for this conformity in the model of the PC of a glow discharge in the mixture of inert gases and chlorine. However, radial field $E_r$ can be disregarded in estimating the ion temperatures. The smallness of the contribution of the ion current to the total current of the discharge, which had earlier only been postulated, is demonstrated. It is shown that diffusion-aided removal is the predominant mechanism of perishing of electrons and positive ions; for this reason, electron-ion recombination (as well as ion-ion recombination in the balance of positive ions) can be disregarded.