Transport in a toroidally confined pure electron plasma

Journal Article · Mon Jul 01 04:00:00 EDT 1996 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.871971· OSTI ID:285572

Crooks, S M; ONeil, T M ^[1]

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1. Department of Physics 0319, University of California at San Diego, La Jolla, California 92093-0319 (United States)

O{close_quote}Neil and Smith [T.M. O{close_quote}Neil and R.A. Smith, Phys. Plasmas {bold 1}, 8 (1994)] have argued that a pure electron plasma can be confined stably in a toroidal magnetic field configuration. This paper shows that the toroidal curvature of the magnetic field of necessity causes slow cross-field transport. The transport mechanism is similar to magnetic pumping and may be understood by considering a single flux tube of plasma. As the flux tube of plasma undergoes poloidal {ital E}{bold {times}}{ital B} drift rotation about the center of the plasma, the length of the flux tube and the magnetic field strength within the flux tube oscillate, and this produces corresponding oscillations in {ital T}{sub {parallel}} and {ital T}{sub {perpendicular}}. The collisional relaxation of {ital T}{sub {parallel}} toward {ital T}{sub {perpendicular}} produces a slow dissipation of electrostatic energy into heat and a consequent expansion (cross-field transport) of the plasma. In the limit where the cross section of the plasma is nearly circular the radial particle flux is given by {Gamma}{sub {ital r}}=1/2{nu}{sub {perpendicular},{parallel}}{ital T}({ital r}/{rho}{sub 0}){sup 2}{ital n}/({minus}{ital e}{partial_derivative}{Phi}/{partial_derivative}{ital r}), where {nu}{sub {perpendicular},{parallel}} is the collisional equipartition rate, {rho}{sub 0} is the major radius at the center of the plasma, and {ital r} is the minor radius measured from the center of the plasma. The transport flux is first calculated using this simple physical picture and then is calculated by solving the drift-kinetic Boltzmann equation. This latter calculation is not limited to a plasma with a circular cross section. {copyright} {ital 1996 American Institute of Physics.}

• OSTI ID: 285572
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 7 Vol. 3; ISSN 1070-664X; ISSN PHPAEN
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
COLLISIONAL PLASMA
ELECTRON GAS
KINETIC EQUATIONS
PLASMA CONFINEMENT
PLASMA DRIFT
ROTATING PLASMA
TOROIDAL CONFIGURATION
TRANSPORT THEORY