Charge of a Particle-Absorbing Sphere in Collisionless Plasma by the Results of a Direct Numerical Experiment

Abstract

The process of charging of a spherical body absorbing plasma electrons and ions is modeled by directly solving the Vlasov–Poisson equations. The main goal of the numerical experiment is to determine the sphere charge in a stable steady state established on long times in perturbed plasma. Special attention is paid to the contribution of trapped ions moving in finite orbits to the screening of a charged body. The charge of the trapped particle cloud is determined as a function of the body size in a wide parameter range of an initially unperturbed plasma.