Simulation of the layer of non-equilibrium ionization in a high-pressure argon plasma with multiply-charged ions

Deviations from ionization equilibrium caused by diffusion in the near-cath ode region of an atmospheric-pressure argon are discharge are studied. The model comprises the continuity and transport equations for electrons, atoms , and singly-, doubly- and triply-charged ions. A numerical solution of the se equations is obtained in a wide range of electron temperatures in the la yer. Distributions of densities of the species across the layer and the ion currents to the cathode are presented. It is shown that in the whole range of the electron temperatures the major contribution to the total ion curre nt to the cathode is due to singly-charged ions. A comparison is presented of the obtained numerical results with those given by a model with only sin gly-charged ions.