Dust particle charging in DC glow discharge plasma

摘要

Dust particles charging in a stratified positive column of a low-pressure DC glow discharge wasinvestigated theoretically. The presented model consists of (I) previously developed 1D self-consistentmodel for discharge parameters on the tube axis; (ii) ambipolar approximation for radialelectric potential distribution and the assumption that the electron energy distribution function inradial direction depends on the total electron energy only; (iii) orbital motion limited model for theprocesses of particle charging. For a probe particle, the 2D radial and axial charge distributions areobtained. It was shown that the particle charge strongly depends on the obtained non-Maxwellianelectron energy distribution function and on the electric field distribution in the discharge tube. Theobtained radial charge distribution is non-homogeneous that can lead to the complex motion of theparticles, e.g., vortex motion of particles near the tube walls obtained in experiments.