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Title: A destabilizing effect of rotation shear on magnetohydrodynamic ballooning modes

Abstract

The destabilization of ideal magnetohydrodynamic ballooning modes at finite rotation shear is demonstrated for the model s-{alpha} equilibrium by exploiting low magnetic shear, s, to simplify the two-dimensional stability problem to a one-dimensional eigenvalue problem. This simpler calculation captures the same features as exhibited by a full two-dimensional treatment, namely that stable values in the s-{alpha} stability diagram become unstable above a critical rotation shear. The first and second stability boundaries at low s are calculated as functions of rotation shear.

Authors:
; ;  [1]
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  1. EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxfordshire, OX14 3DB (United Kingdom)
Publication Date:
OSTI Identifier:
20974954
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 4; Other Information: DOI: 10.1063/1.2718909; (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; BALLOONING INSTABILITY; DIAGRAMS; EIGENFUNCTIONS; EIGENVALUES; EQUILIBRIUM; MAGNETOHYDRODYNAMICS; ONE-DIMENSIONAL CALCULATIONS; PLASMA; ROTATION; SHEAR; STABILITY; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Connor, J. W., Hastie, R. J., and Webster, A. J. A destabilizing effect of rotation shear on magnetohydrodynamic ballooning modes. United States: N. p., 2007. Web. doi:10.1063/1.2718909.
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Connor, J. W., Hastie, R. J., & Webster, A. J. A destabilizing effect of rotation shear on magnetohydrodynamic ballooning modes. United States. doi:10.1063/1.2718909.
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Connor, J. W., Hastie, R. J., and Webster, A. J. Sun . "A destabilizing effect of rotation shear on magnetohydrodynamic ballooning modes". United States. doi:10.1063/1.2718909.
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@article{osti_20974954,
title = {A destabilizing effect of rotation shear on magnetohydrodynamic ballooning modes},
author = {Connor, J. W. and Hastie, R. J. and Webster, A. J.},
abstractNote = {The destabilization of ideal magnetohydrodynamic ballooning modes at finite rotation shear is demonstrated for the model s-{alpha} equilibrium by exploiting low magnetic shear, s, to simplify the two-dimensional stability problem to a one-dimensional eigenvalue problem. This simpler calculation captures the same features as exhibited by a full two-dimensional treatment, namely that stable values in the s-{alpha} stability diagram become unstable above a critical rotation shear. The first and second stability boundaries at low s are calculated as functions of rotation shear.},
doi = {10.1063/1.2718909},
journal = {Physics of Plasmas},
number = 4,
volume = 14,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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Journal Article:
DOI:  10.1063/1.2718909
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  • ; - Physical Review Letters
    A ballooning perturbation in a toroidally rotating tokamak is expanded by square-integrable eigenfunctions of an eigenvalue problem associated with ballooning modes in a static plasma. Especially a weight function is chosen such that the eigenvalue problem has only the discrete spectrum. The eigenvalues evolve in time owing to toroidal rotation shear, resulting in a countably infinite number of crossings among them. The crossings cause energy transfer from an unstable mode to the infinite number of stable modes; such transfer works as the stabilization mechanism of the ballooning mode.

  • ; - Phys. Fluids; (United States)
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