Fast wave heating and current drive in JET : Present results and future plansFunded under: FP2-FUSION 10C
A review is given of recent fast wave heating and current drive experiments on the JET tokamak. The heating studies encompass both minority cyclotron damping and direct electron absorption of the fast wave. In these experiments, a maximum power level of 22 MW has been coupled to limiter plasmas. Bulk ion heating by minority ICRH has been demonstrated both in plasmas near the density limit and in pellet fuelled H-mode discharges which reached a record thermal fusion product of 7.8 x 1.0 E20 skeV/m3. Electron heating by highly energetic minority tails appears to produce a saturation in the central electron temperature with increasing power per electron. Broadening of the heating profile by fast ion orbit effects could be the cause of this saturation. Current drive experiments include synergistic effects with LHCD, boostrap current with ICRF alone and minority ion current drive. The combination of LHCD and ICRH with monopole phasing produces an efficiency factor gamma = 0.4 x 1.0 E20 A/Wm2 due to damping of fast waves on the tail electrons generated by the LHCD. The broadening of the current profile stabilises the sawteeth. An optimum power level is found for stability as expected from minority current drive theory.
Bibliographic Reference: Report: JET-P(91)63 EN (1991) 17 pp.
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon. OX14 3EA (GB)
Record Number: 199210517 / Last updated on: 1994-12-02
Original language: en
Available languages: en