Resonant interaction of energetic ions with magnetic islands

A resonance omega = k(parallel to)v(parallel to) between energetic ions and a magnetic island with a half-width greater than the bulk ion Larmor radiu s is considered. As a result of such a resonant interaction, energetic ions with a relative density of a few per cent contribute significantly to the toroidal torque balance, leading to considerable modification of the equili brium island rotation frequency omega. The possibility of a frequency pulsa tion scenario, instead of a stationary toroidal torque balance, is indicate d.