Linear theory of electron-plasma waves at arbitrary collisionality. (April 2019)

• Record Type: Journal Article
• Authors: Jorge, R.; Ricci, P.; Brunner, S.; Gamba, S.; Konovets, V.; Loureiro, N. F.; Perrone, L. M.; Teixeira, N.
• Is Part Of: Journal of plasma physics. Volume 85:Number 2(2019)
• Publication Date: 2019-04
• Subjects: plasma waves; Plasma (Ionized gases) -- Periodicals; 530.4405
• DOI: 10.1017/S0022377819000266
• Languages: English
• ISSNs: 0022-3778

Abstract

Abstract : The dynamics of electron-plasma waves is 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.