Numerical solution of ionization equations by the fractional step method

The fractional step method is used to solve the ionization equations for electron-ion plasma containing neutrals in relation to processes in stationary plasma thrusters (SPT). The method uses splitting with respect to physical processes: the evolution of plasma is represented as a superposition of pure transport in an external field in phase space with subsequent ionization. The transport is calculated using the macroparticle method. The ionization process in the case of plane symmetry is calculated using explicit analytical formulas. The resulting formulas of the fractional step method are compared with the numerical solution of the plasma evolution equation using the known physical model of ionization.