Compressibility effect on magnetic-shear-localized ideal magnetohydrodynamic interchange instability
نویسندگان
چکیده
Sangeeta Gupta, J. D. Callen and C. C. Hegna Department of Engineering Physics, University of Wisconsin, Madison, WI 53706-1687 (Dated: July 8, 2004) Abstract Eigenmode analysis of a magnetic-shear-localized ideal magnetohydrodynamic (MHD) interchange instability in the presence of plasma compressibility indicates the marginal stability criterion (DI = 1/4) is not affected by the compressibility effects. Above the marginal stability criterion, plasma compressibility reduces the growth rate of ideal interchange instability. Including compressibility effects, robust shear-localized ideal MHD instabilities require DI & 3/4, a factor of about 3 above the usual Suydam/Mercier instability criterion (DI > 1/4).
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