Ballooning stability of a toroidally rotating plasma

The stability of high (m, n) ideal ballooning modes in a toroidal plasma experiencing a rigid rotation about its axis of symmetry is investigated. Centrifugal forces induce poloidal asymmetry in the plasma pressure and affect the position and form of the magnetic surfaces. This leads to stabilization of the ballooning modes in all but the outer plasma regions (i.e for r < L p , where L p is the pressure scale length). Stabilization is possible for rather modest values of the parameter , where ∊ is the inverse aspect ratio, V 0 is the rotation velocity and C s is the sound velocity. The analysis also indicates that plasma rotation can help gain access to the second stability regime in high beta experiments.