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Title: The influence of the ion polarization current on magnetic island stability in a tokamak plasma

Abstract

The influence of the ion polarization current on the stability of a constant-{psi} magnetic island in a tokamak plasma is investigated numerically using a reduced two-fluid model in two-dimensional slab geometry. The polarization current is found to be negligibly small when the island is either too narrow or too wide. However, under certain circumstances, there exists an intermediate regime in which the polarization current is appreciable, and has a stabilizing influence on the island. This effect may account for the metastable nature of neoclassical tearing modes in tokamak plasmas.

Authors:
; ;  [1]
  1. Institute for Fusion Studies, Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)
Publication Date:
OSTI Identifier:
20860441
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 12; Other Information: DOI: 10.1063/1.2402914; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTRIC CURRENTS; GEOMETRY; IONS; MAGNETIC ISLANDS; MAGNETOHYDRODYNAMICS; NEOCLASSICAL TRANSPORT THEORY; NUMERICAL ANALYSIS; PLASMA; PLASMA CONFINEMENT; POLARIZATION; RADIATION TRANSPORT; STABILITY; TEARING INSTABILITY; TOKAMAK DEVICES; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Fitzpatrick, R., Waelbroeck, F. L., and Militello, F.. The influence of the ion polarization current on magnetic island stability in a tokamak plasma. United States: N. p., 2006. Web. doi:10.1063/1.2402914.
Fitzpatrick, R., Waelbroeck, F. L., & Militello, F.. The influence of the ion polarization current on magnetic island stability in a tokamak plasma. United States. doi:10.1063/1.2402914.
Fitzpatrick, R., Waelbroeck, F. L., and Militello, F.. Fri . "The influence of the ion polarization current on magnetic island stability in a tokamak plasma". United States. doi:10.1063/1.2402914.
@article{osti_20860441,
title = {The influence of the ion polarization current on magnetic island stability in a tokamak plasma},
author = {Fitzpatrick, R. and Waelbroeck, F. L. and Militello, F.},
abstractNote = {The influence of the ion polarization current on the stability of a constant-{psi} magnetic island in a tokamak plasma is investigated numerically using a reduced two-fluid model in two-dimensional slab geometry. The polarization current is found to be negligibly small when the island is either too narrow or too wide. However, under certain circumstances, there exists an intermediate regime in which the polarization current is appreciable, and has a stabilizing influence on the island. This effect may account for the metastable nature of neoclassical tearing modes in tokamak plasmas.},
doi = {10.1063/1.2402914},
journal = {Physics of Plasmas},
number = 12,
volume = 13,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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