Temperature of ion cyclotron heated impurity ions in fusion plasmas

Abstract

The temperature of impurity ions in fusion plasmas is normally assumed to be the same as that of background particles. This assumption can be, however, violated for selective impurity species intensively heated by radio frequency waves or in reactor plasmas of low collisionality. An approach to compute the impurity temperature under such conditions is elaborated. It is based on the construction of a hierarchy of approximate solutions to the impurity heat balance equation and takes into account that the density and, thus, the heat conductivity of heated ion species can change by many orders of magnitude with the position in the plasma. Coupled with the wave propagation code, the particle and heat balances for impurity and main plasma species provide a self-consistent approach to model the ion cyclotron resonance heating scenario.