Relaxation of the Velocity Distribution of Ions in a Plasma —Application of the Unified Theory—

Abstract

A relaxation equation for the velocity distribution of the ions in a plasma is derived from the convergent kinetic equation taking account of both the short-range and collective interactions. The equation is solved by expanding the distortion of the distribution from equilibrium into a series of orthogonal polynomials. The rate of relaxation of each mode is obtained exactly without any cut-off procedure. The Coulomb logarithms in the rates of each mode are different from each other.