EFFECT OF THE TEMPERATURE-GRADIENT ON NEOCLASSICAL IDEAL INTERNAL KINK MODES

The effect of a temperature gradient on neoclassical ideal internal m = 1 kink modes is studied theoretically. The ideal MHD instability of these modes is assumed to be suppressed by the effects of the finite i on Larmor radius. A study is made of the growth (or damping) of these modes caused by collisional dissipation due to circulating ions. The m ode with a frequency close to that of the ion drift, which is unstable in the case of a uniform temperature of the plasma, is shown to damp when the ion-temperature gradient is not too small. It is noted that t his mode is similar to the fishbone oscillations excited by the energe tic ions.