Tearing-mode stability of tokamak plasmas with elliptical cross-section

Abstract
The effect of the ellipticity of the plasma cross-section on tearing-mode stability is investigated. The induced coupling between modes is shown to be de-stabilizing. The modification of the equilibrium tends, howeyer, to stabilize the tearing modes. The net effect depends on the manner in which the equilibrium is modified as the plasma cross-section shape is changed.