Quasilinear Spatial Diffusion Revisited

Abstract

The complete quasilinear equation is used to describe distribution functions and spatial diffusion of charged particles across a straight magnetic field, due to electrostatic fluctuations. The Non-Markovian terms in the quasilinear equation appear to be important to recover the Ichimaru-Rosenbluth result originally deduced from trajectory calculation of guiding centers. Additional finite Larmor radius contributions can however be of the same order for present Tokamak magnetic fields, when parallel electric fields are present in the turbulent spectrum.