Phase-space diffusion in turbulent plasmas: The random acceleration problem revisited

Phase-space diffusion of test particles in turbulent plasmas is studied by an approach based on a conditional statistical analysis of fluctuating electrostatic fields. Analytical relations between relevant conditional averages and higher-order correlations, <E(n)(x0,t0)E(x0 + x,t0 + t)>, and triple correlations, <E(n)(x0,t0)E(x0 + x,t0 + t)E(x0 + y,t0, + s)>, facilitate considerably the practical application of the resulting equations.