The influence of pure electron heating versus combined electron and ion heating on a high collisionality H-mode plasma has been investigated in ASDEX Upgrade. This was done by replacing both neutral beam injection (NBI) and ion cyclotron resonance frequency (ICRF) heating in small steps with electron cyclotron resonance heating (ECRH) while keeping the total heating power constant. The stability of the global plasma parameters and the response of the kinetic profiles on the changed heating mix and torque input is shown. The differences in edge localized mode behaviour between the different heating mixes is reported. The data were analysed with an interpretative transport model and linear gyrokinetic simulations were performed to evaluate the underlying transport mechanism.
Ion cyclotron range of frequencies heating and high-energy particle production in the Large Helical Device