NONLINEAR RELAXATION OF A NONNEUTRAL ELECTRON-PLASMA DUE TO ELASTIC COLLISIONS WITH BACKGROUND NEUTRAL GAS

The expansion and nonlinear relaxation of a strongly-magnetized nonneutral electron plasma due to elastic collisions with constant collision frequency nu(en) between the plasma electrons and a low-density background neutral gas are investigated theoretically. An important consequence of the analysis is that electron-neutral collisions (nu(en) # 0) cause the electron density profile to relax to a (slowly expanding) quasi-equilibrium state with identical profile shape eta(eq)(rho) to that which would be produced by relaxation to thermal equilibrium by electron-electron collisions in the absence of background neutral gas (nu(en) = 0).