On Quasilinear Perpendicular Diffusion

O. Stawicki

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On Quasilinear Perpendicular Diffusion

O. Stawicki

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Abstract

Quasilinear perpendicular diffusion of charged particles in fluctuating electromagnetic fields is the focus of this paper. A general transport parameter for perpendicular diffusion is presented being valid for an arbitrary turbulence geometry and a plasma wave dispersion relation varying arbitrarily in wavevector. The new diffusion coefficient is evaluated in detail for slab turbulence geometry for two special cases: (1) Alfvénic turbulence and (2) dynamical magnetic turbulence. Furthermore, perpendicular diffusion in 2D geometry is considered for a purely dynamical magnetic turbulence. The derivations and numerical calculations presented here cast serious doubts on the applicability of quasilinear theory for perpendicular diffusion. Furthermore, they emphasize that nonlinear effects play a crucial role in the context of perpendicular diffusion.

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O. Stawicki. 2005-03-26. On Quasilinear Perpendicular Diffusion. https://arxiv.org/abs/astro-ph/0503576

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