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arXiv · 1608.02742

NORSE: A solver for the relativistic non-linear Fokker-Planck equation for electrons in a homogeneous plasma

A. Stahl·M. Landreman·O. Embréus·T. Fülöp
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Abstract

Energetic electrons are of interest in many types of plasmas, however previous modeling of their properties has been restricted to the use of linear Fokker-Planck collision operators or non-relativistic formulations. Here, we describe a fully non-linear kinetic-equation solver, capable of handling large electric-field strengths (compared to the Dreicer field) and relativistic temperatures. This tool allows modeling of the momentum-space dynamics of the electrons in cases where strong departures from Maxwellian distributions may arise. As an example, we consider electron runaway in magnetic-confinement fusion plasmas and describe a transition to electron slide-away at field strengths significantly lower than previously predicted.

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A. Stahl, M. Landreman, O. Embréus, T. Fülöp. 2016-08-09. NORSE: A solver for the relativistic non-linear Fokker-Planck equation for electrons in a homogeneous plasma. https://doi.org/10.1016/j.cpc.2016.10.024

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