Journal article
Localized bulk electron heating with ICRF mode conversion in the JET tokamak
Ion cyclotron resonance frequencies (ICRF) mode conversion has been developed for localized on-axis and off-axis bulk electron heating on the JET tokamak. The fast magnetosonic waves launched from the low-field side ICRF antennas are mode-converted to short-wavelength waves on the high-field side of the He-3 ion cyclotron resonance layer in D and He-4 plasmas and subsequently damped on the bulk electrons.
The resulting electron power deposition, measured using ICRF power modulation, is narrow with a typical full-width at half-maximum of approximate to30 cm (i.e. about 30% of the minor radius) and the total deposited power to electrons comprises at least up to 80% of the applied ICRF power. The ICRF mode conversion power deposition has been kept constant using He-3 bleed throughout the ICRF phase with a typical duration of 4-6 s, i.e. 15-40 energy confinement times.
Using waves propagating in the counter-current direction minimizes competing ion damping in the presence of co-injected deuterium beam ions.
Language: | English |
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Year: | 2004 |
Pages: | 33-46 |
ISSN: | 10185577 , 00295515 and 17414326 |
Types: | Journal article |
DOI: | 10.1088/0029-5515/44/1/004 |