Spatially resolved toroidal plasma rotation with ICRF on JET
Plasmas heated by ICRF only in the JET tokamak show distinct structures in the toroidal rotation profile, with regions where &ddiff; omega/&ddiff;r>0 when the minority cyclotron resonance layer is far off-axis. The rotation is dominantly co-current with a clear off-axis maximum. There is only a slight difference between a high-field side (HFS) or a low-field side position of this resonance layer: the off-axis maximum in the rotation profile is modestly higher for the HFS position. This is in contrast to the predictions of theories that rely mainly on the effects arising from ICRF-driven fast ions to account for ICRF-induced plasma rotation. The differences due to the direction of the antenna spectrum (co- or counter-) are small. A more central deposition of the ICRF power in L-mode and operation in H-mode both lead to more centrally peaked profiles, both in the co-direction. Strong MHD modes brake the rotation and lead to overall flat rotation profiles.
Bibliographic Reference: An article published in: Nuclear Fusion, 43 (April 2003) pp.274-289
Availability: This article can be accessed online by subscribers, and can be ordered online by non-subscribers, at: http://stacks.iop.org/0029-5515/43/274
Record Number: 200316350 / Last updated on: 2003-06-17
Original language: en
Available languages: en