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arXiv · 1811.12855

Linear Theory of Electron-Plasma Waves at Arbitrary Collisionality

R. Jorge·P. Ricci·S. Brunner·S. Gamba·V. Konovets·N. F. Loureiro·L. M. Perrone·N. Teixeira
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Abstract

The dynamics of electron-plasma waves are described at arbitrary collisionality by considering the full Coulomb collision operator. The description is based on a Hermite-Laguerre decomposition of the velocity dependence of the electron distribution function. The damping rate, frequency, and eigenmode spectrum of electron-plasma waves are found as functions of the collision frequency and wavelength. A comparison is made between the collisionless Landau damping limit, the Lenard-Bernstein and Dougherty collision operators, and the electron-ion collision operator, finding large deviations in the damping rates and eigenmode spectra. A purely damped entropy mode, characteristic of a plasma where pitch-angle scattering effects are dominant with respect to collisionless effects, is shown to emerge numerically, and its dispersion relation is analytically derived. It is shown that such a mode is absent when simplified collision operators are used, and that like-particle collisions strongly influence the damping rate of the entropy mode.

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R. Jorge, P. Ricci, S. Brunner, S. Gamba, V. Konovets, N. F. Loureiro, L. M. Perrone, N. Teixeira. 2018-11-26. Linear Theory of Electron-Plasma Waves at Arbitrary Collisionality. https://doi.org/10.1017/s0022377819000266

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