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Neoclassical transport processes in weakly collisional plasmas with fractured velocity distribution functions

Part of: Collisions in Collisionless Plasmas Focus on Fusion

Published online by Cambridge University Press:  15 September 2014

A. A. Kabantsev ,
C. F. Driscoll ,
D. H. E. Dubin  and
Yu. A. Tsidulko
A. A. Kabantsev*
Affiliation:
University of California at San Diego, La Jolla, CA 92093, USA
C. F. Driscoll
Affiliation:
University of California at San Diego, La Jolla, CA 92093, USA
D. H. E. Dubin
Affiliation:
University of California at San Diego, La Jolla, CA 92093, USA
Yu. A. Tsidulko
Affiliation:
Budker Institute of Nuclear Physics, Novosibirsk 630090, Russian Federation
*
†Email address for correspondence: akabantsev@ucsd.edu
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Abstract

Ripples in magnetic or electrostatic confinement fields give rise to trapping separatrices, and conventional neoclassical transport theory describes the collisional trapping/detrapping of particles with fractured distribution function. Our experiments and novel theory have now characterized a new kind of neoclassical transport processes arising from chaotic (nominally collisionless) separatrix crossings, which occur due to E × B plasma rotation along θ−ruffled or wave-perturbed separatrices. This chaotic neoclassical transport becomes dominant at low collisionality when the collisional spreading of particle energy during the dynamical period is less than the separatrix energy ruffle.

Type
Research Article
Information
Journal of Plasma Physics , Volume 81 , Issue 1 , January 2015 , 305810105
Copyright
Copyright © Cambridge University Press 2014 

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