Analysis of minority velocity distribution and power deposition profile in icrf heating in a tokamak

The power deposition profile in the two-ion hybrid resonance heating regime in tokamaks is studied by including the modification of the minority ion velocity distribution. The Fokker-Planck equation and the kinetic wave equation are solved numerically in order to describe the time evolution of the velocity distribution and the deposition profile. The power that is transferred coUisionally to the electrons and majority ions from the minority ions is also calculated. Application to the JET plasma demonstrates strong electron heating near the plasma centre. Control of the deposition profile by varying the minority ion concentration and the magnitude of the magnetic field is also discussed.