Nonlinear gyroviscous force in a collisionless plasma

Authors
Citation
Ev. Belova, Nonlinear gyroviscous force in a collisionless plasma, PHYS PLASMA, 8(9), 2001, pp. 3936-3944
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICS OF PLASMAS
ISSN journal
1070-664X → ACNP
Volume
8
Issue
9
Year of publication
2001
Pages
3936 - 3944
Database
ISI
SICI code
1070-664X(200109)8:9<3936:NGFIAC>2.0.ZU;2-F
Abstract
Nonlinear gyroviscous forces in a collisionless plasma with temperature var iations are calculated from the gyrofluid moments of the gyrokinetic Vlasov equation. The low-frequency gyrokinetic ordering and electrostatic perturb ations are assumed, and an additional finite Larmor radius (FLR) expansion in a parameter epsilon (perpendicular to) equivalent to (k(perpendicular to )rho)(2) < 1 is performed. This approach leads naturally to an expression f or the gyroviscous force, (del . pi (g)), in terms of the gyrocenter distri bution function, thus including all resonant effects, and represents a syst ematic FLR expansion in a general form (no assumption of any closure is mad e). The expression of (del . pi (g)) is also calculated in terms of the par ticle-fluid moments by making the transformation from the gyrocenter to par ticle coordinates. The calculated (del . pi (g)) represents a modification of the Braginskii gyroviscosity for a collisionless plasma with delT not eq ual 0. It is compared with previous calculations based on the traditional f luid approach. As a byproduct of the gyroviscosity calculations, we derive a set of nonlinear reduced gyrofluid (and a corresponding set of particle-f luid) moment equations with FLR corrections, which exhibit a generalized fo rm of the "gyroviscous cancellation." (C) 2001 American Institute of Physic s.