Particle trapping effects on transport in random electric field

Test particle diffusion in a random electric field across uniform magnetic field is studied using analytical approach and direct numerical simulation. Our approximation describes particle trapping and is able to reproduce an asymptotically zero diffusion coefficient for infinite Kubo number, i.e. dimensionless correlation time. For large, but finite, correlation times the subdiffusive scaling relation for asymptotic diffusion coefficient is obtained. The considered approach also recovers the known scaling relation for small correlation times. The accurate method to take into account finite Larmor radius effects is demonstrated. (paper)