ICRF direct electron heating experiments in TFTR

Direct electron damping of the fast wave is a prerequisite to a viable current drive scenario for future steady-state tokamaks. It is also an attractive heating alternative to the standard ion resonance heating methods for DT experiments on TFTR because it does not require the addition of non-reactive ion species and avoids minority ion tails during studies of alpha-particle effects. The absence of minority ions in direct electron heating (DEH) also allows the use of RF power modulation to determine power deposition profiles and to carry out modulation transport studies to characterize electron transport in supershot plasmas, as described in this paper. (author) 10 refs., 5 figs