ICRF heating of JET plasmas with the third-harmonic deuterium resonance
Ion cyclotron range of frequencies (ICRF) heating experiments with the third-harmonic deuterium resonance in the plasma centre have been carried out at the Joint European Torus (JET). These experiments were the first to demonstrate third-harmonic damping on initially Maxwellian plasmas. A record DD-fusion reaction rate for ICRF-only heating on JET was achieved. In contrast to TORE SUPRA results for a similar ICRF scenario, the power absorbed directly by electrons was found to be relatively low. The difference between JET and TORE SUPRA data is attributed to the good confinement of MeV ions in JET allowing substantial fast ion tails to develop and thus large damping at the third-harmonic resonance to take place. The discharges have been simulated with the PION code (self-consistent calculation of the evolution of distribution function and ICRF power deposition). To obtain reasonable agreement between the measurements and simulations, three additions to the PION code were necessary: parasitic absorption at the plasma edge; a particle loss term that removes particles above 4 MeV; a sawtooth model which accounts in a simplified way for the redistribution of fast ions at the sawtooth crashes.
Bibliographic Reference: Report: JET-P (97) 17 EN (1997) 25pp.
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (GB)
Record Number: 199711333 / Last updated on: 1997-10-16
Original language: en
Available languages: en