Effect of ion cyclotron parametric turbulence on the generation of edge suprathermal ions during ion cyclotron plasma heating

Abstract

The effect of parametric ion cyclotron turbulence on the heating of cold and suprathermal ions in the edge of a tokamak plasma during injection of high radio frequency (rf) power in the ion cyclotron resonance frequency range is studied. The maximum turbulent heating rates for cold edge ions and suprathermal edge ions are calculated analytically for ion cyclotron turbulence driven by rf heating at the plasma edge. It is demonstrated that the maximum turbulent ion-heating rate for suprathermal ions is insufficient to explain the observed heating of edge ions. Therefore, the excitation of ion cyclotron turbulence by rf heating systems in the plasma edge is unlikely to be responsible for the experimentally observed large population of suprathermal ions in the edge of tokamak plasmas.