Hot particle stabilization of ballooning modes in tokamaks

Abstract

The concept of energetic particle stabilization of ballooning modes in tokamaks is extended by considering numerically generated finite aspect ratio equilibria and attempting to simultaneously stabilize all flux surfaces against ballooning modes by suitable choice of a hot particle anisotropic pressure. To achieve access to the second stability regime at as low a beta value as possible, tokamaks with circular cross-section and an aspect ratio of ten are considered. Global stabilization of ballooning modes is demonstrated, even though the drift reversal constraint requires careful tailoring of the anisotropic pressure profile. A prescription for determining the optimum anisotropic pressure profiles for any equilibrium is provided.