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Title: Effect of an error field on the stability of the resistive wall mode

Abstract

A simple model of the resistive wall mode (RWM) in a rotating tokamak plasma subject to a static error field is constructed, and then used to investigate RWM stability in a DIII-D-like [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] plasma. An error field as small as 10 G (i.e., about 5x10{sup -4} of the toroidal field) is found to significantly increase the critical plasma rotation frequency needed to stabilize the RWM. Such an error field also profoundly changes the nature of the RWM onset. At small error-field amplitudes, the RWM switches on gradually as the plasma rotation is gradually reduced. On the other hand, at large error-field amplitudes, there is a sudden collapse of the plasma rotation as the rotation frequency falls below some critical value. This collapse is associated with a very rapid switch-on of the RWM.

Authors:
 [1]
  1. Institute for Fusion Studies, Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)
Publication Date:
OSTI Identifier:
20974835
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 2; Other Information: DOI: 10.1063/1.2446041; (c) 2007 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; AMPLITUDES; DOUBLET-3 DEVICE; ERRORS; MAGNETOHYDRODYNAMICS; PLASMA; PLASMA CONFINEMENT; PLASMA INSTABILITY; ROTATION; STABILITY; SWITCHES; WALL EFFECTS

Citation Formats

Fitzpatrick, Richard. Effect of an error field on the stability of the resistive wall mode. United States: N. p., 2007. Web. doi:10.1063/1.2446041.
Fitzpatrick, Richard. Effect of an error field on the stability of the resistive wall mode. United States. doi:10.1063/1.2446041.
Fitzpatrick, Richard. Thu . "Effect of an error field on the stability of the resistive wall mode". United States. doi:10.1063/1.2446041.
@article{osti_20974835,
title = {Effect of an error field on the stability of the resistive wall mode},
author = {Fitzpatrick, Richard},
abstractNote = {A simple model of the resistive wall mode (RWM) in a rotating tokamak plasma subject to a static error field is constructed, and then used to investigate RWM stability in a DIII-D-like [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] plasma. An error field as small as 10 G (i.e., about 5x10{sup -4} of the toroidal field) is found to significantly increase the critical plasma rotation frequency needed to stabilize the RWM. Such an error field also profoundly changes the nature of the RWM onset. At small error-field amplitudes, the RWM switches on gradually as the plasma rotation is gradually reduced. On the other hand, at large error-field amplitudes, there is a sudden collapse of the plasma rotation as the rotation frequency falls below some critical value. This collapse is associated with a very rapid switch-on of the RWM.},
doi = {10.1063/1.2446041},
journal = {Physics of Plasmas},
number = 2,
volume = 14,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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