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arXiv · 1407.5788

Quasi-linear analysis of the extraordinary electron wave destabilized by runaway electrons

G. I. Pokol·A. Kómár·A. Budai·A. Stahl·T. Fülöp
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Abstract

Runaway electrons with strongly anisotropic distributions present in post-disruption tokamak plasmas can destabilize the extraordinary electron (EXEL) wave. The present work investigates the dynamics of the quasi-linear evolution of the EXEL instability for a range of different plasma parameters using a model runaway distribution function valid for highly relativistic runaway electron beams produced primarily by the avalanche process. Simulations show a rapid pitch-angle scattering of the runaway electrons in the high energy tail on the $100-1000\;\rm μs$ time scale. Due to the wave-particle interaction, a modification to the synchrotron radiation spectrum emitted by the runaway electron population is foreseen, exposing a possible experimental detection method for such an interaction.

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G. I. Pokol, A. Kómár, A. Budai, A. Stahl, T. Fülöp. 2014-10-03. Quasi-linear analysis of the extraordinary electron wave destabilized by runaway electrons. https://doi.org/10.1063/1.4895513

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