Transport to thermal equilibrium of a pure electron plasma

Abstract

The transport of a pure electron plasma column across an axial magnetic field is considered, the transport being due to binary electron–electron collisions. The Boltzmann equation is expanded in inverse powers of the magnetic field, with the radial electric field and density gradient ordered self-consistently. The first nonvanishing terms in the particle flux involve the third derivative of the density and the second derivative of the electric field. An H theorem is used to show that this flux drives the plasma to a confined thermal equilibrium density profile. The electrons can come to thermal equilibrium with each other and still be confined magnetically, since the total canonical angular momentum is conserved. The final equilibrium can be predicted from the initial total number of particles, angular momentum, and energy. The approach to equilibrium is shown in a numerical example.