Observations of Up-down differences in Plasma Response during ECRH on TCV
The TCV ECW system, when complete, will provide 3 MX X2 and 1.5MW X3 for 2 seconds. Present ECRH experiments have been carried out using up to 1MW of power. Differences in Sawtooth activity have been seen during magnetic field scans, plasma vertical displacement and mirror launching angle scans. These differences are strongly correlated with with the position of the heating relative to the inversion radius of the sawteeth. In addition, we have observed small but reproducible differences between the central electron temperature, X-rat intensity and hot ion tail temperature when heating above or below the plasma midplane. There are several possible explanations for these differences; perhaps the most plausible is that the asymmetry in the field line geometry, due to the presence of the poloidal field, leads to a small current drive component during ECRH even at perpendicular injection.
Bibliographic Reference: Article: Proceedings Vol I of 1998 International Congress on Plasma Physics 25th EPS Conference on Controlled Fusion and Plasma Physics, (1998)
Record Number: 199910923 / Last updated on: 1999-07-05
Original language: en
Available languages: en