The electromagnetic power in the ion cyclotron frequency range radiated by atokamak plasma with energetic ions is considered. It is found that the radiation mayresult from plasma fluctuations which are associated with the edge localized fastmagnetoacoustic eigenmodes and strongly enhanced by interaction with theenergetic ions. In this case, almost all the energy transferred from the energetic particlesto the waves is emitted by the plasma and the system is marginally stable due to thepresence of small wave damping. In particular, this picture is consistent with thepower measurements of superthermal ion cyclotron emission in the JET preliminarytritium experiment.
Nonlinear parametric phenomena in plasma during radio frequency heating in the ion cyclotron frequency range