On the accuracy of direct simulation the Landau collision integral by the Boltzmann integral

The Landau (Fokker–Planck) integral for Coulomb collisions is an attributive constituent of physical and mathematical models of laboratory and space plasmas, as well, in which regime of intermediate collisionality is important. In this paper the study of direct statistical modeling of the Monte Carlo type method for the kinetic equation with a nonlinear operator LFP for Coulomb collisions is considered. The method is based on the approximation of the Landau collision integral by the Boltzmann integral. The paper has two objectives: first, to get numerical estimates of the approximation order of the Landau collision integral by the Boltzmann integral; and secondly, to explore the possibility of optimization of algorithm for the multicharged ions. The results are illustrated by simulation of the relaxation problem for one and two components.