Strongly coupled nonneutral plasmas: equilibrium and relaxation in two-component plasmas in Penning-Malmberg trap

The relaxation processes and the equilibrium distribution of two-component nonneutral plasmas in the Penning-Malmberg trap are analyzed by molecular dynamics simulations and theoretical approaches. As an example, mixtures of antiprotons and electrons for antiproton cooling experiments are considered. The relaxation of antiproton energy is calculated based on the rate equations and it is shown that the slow energy transfer between parallel and perpendicular components of strongly magnetized electrons does not affect the whole relaxation process seriously. The equilibrium distribution of each species are obtained by extensive molecular dynamics simulations for various values of parameters and the results are reproduced by theoretical calculations to a good accuracy. The condition for the centrifugal separation is obtained.