Investigation on dependence of electrons characteristic energy on the similarity variable in diffusion recombination dominated glow discharge pure gases using average degree of ionization as parameter

Through the continuity equation of electrons and positive ions for the radial electron density variation with a time-independent glow discharge in pure media, the diagram of the characteristic energy of the electrons versus similarity variable in glow discharge has been derived, while the linear terms of diffusion and nonlinear of recombination have been considered in the model. The characteristic curves for three gases of CO2, N2, and Helium at constant temperature, and three different degrees of ionization have been derived. It has shown that in the degrees of ionization of 10-3, the curve has been strongly shifted to the high electron temperature, i.e., glow discharge in highly ionized plasmas, which still low electron temperature has been forbidden by recombination process. The effect of the gas kind on the electron temperature in constant similarity variable, has been discussed; also, the difference of the gas flow and gas sealed of glow discharge vessels respect to the similarity variable has been studied.