Theory of two-dimensional mean field electron magnetohydrodynamics

Theoretical studies of mean field electrodynamics for diffusive processes in the electron magnetohydrodynamic (EMHD) model is presented. In contrast to magnetohydrodynamics (MHD), the evolution of the magnetic field here is governed by a nonlinear equation in magnetic field variables. A detailed description of diffusive processes in two dimensions are presented in this paper. In particular, it has been shown analytically that the turbulent magnetic field diffusivity is suppressed from naive quasilinear estimates. It is shown that for complete whistlerization of the spectrum, turbulent diffusivity vanishes. The question of whistlerization of the turbulent spectrum is investigated numerically, and a reasonable tendency towards whistlerization is observed. Numerical studies also show suppression of magnetic field diffusivity in accordance with analytical estimates. (C) 2000 American Institute of Physics. [S1070-664X(00)02901-3].