Linear Theory of Electron-Plasma Waves at Arbitrary Collisionality
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.
- Research Organization:
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center
- Sponsoring Organization:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES)
- DOE Contract Number:
- FG02-91ER54109
- OSTI ID:
- 1880321
- Country of Publication:
- United States
- Language:
- English
Linear theory of electron-plasma waves at arbitrary collisionality
|
journal | April 2019 |
Similar Records
Theory of the Drift-Wave Instability at Arbitrary Collisionality
Theory of the Drift-Wave Instability at Arbitrary Collisionality