Electron heating by ion Bernstein wave in the HT-7 tokamak

Ion Bernstein wave (IBW) heating has been investigated in the HT-7 superconducting tokamak. Electron heating mode was concentrated on deuterium plasma with an injecting power to 320 kW. The bulk electron temperature showed a significant rise with a heating factor, DeltaT(e) x n(e)/P-RF, up to 9.4 eV x 10(13) cm(-3) kW(-1). The direct electron heating via electron Landau damping from IBW has been demonstrated after intensive RF wall conditioning. Both on-axis and off-axis electron heating were obtained. Electron temperature profile was modified by IBW under different plasma conditions. Edge density showed no sharp drop during IBW heating. Plasma density and temperature remained almost unchanged in front of antenna. But edge temperature and density inside of plasma visibly increased and their profiles became steeper. Particle confinement improvement was observed by IBW.