Plasma and Fusion Research

Volume 7, 1202005 (2012)

Rapid Communications

Improvement of EC-Driven Spherical Tokamak Discharge by a Radial Magnetic Perturbation on Energetic Trapped Electrons
Fumitake WATANABE, Masaki UCHIDA, Hitoshi TANAKA and Takashi MAEKAWA
Graduate School of Energy Science, Kyoto University, Kyoto 606-8502, Japan
(Received 9 November 2011 / Accepted 22 December 2011 / Published 27 January 2012)


Effects of a radial magnetic perturbation (MP) on electron cyclotron (EC) driven fast electrons are investigated in the Low Aspect ratio Torus Experiment (LATE) device. When a weak MP is applied to plasmas maintained solely by EC heating and current drive, plasma current and electron density increase, whereas energetic trapped electrons located outside the last closed flux surface (LCFS) on the low field side (LFS) decrease. The effect of MPs on energetic trapped electrons has an important role in improving EC-driven plasma discharges.


Radial magnetic perturbation, spherical tokamak, electron cyclotron heating, current drive, fast electron, energetic passing electron, energetic trapped electron, LATE

DOI: 10.1585/pfr.7.1202005


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This paper may be cited as follows:

Fumitake WATANABE, Masaki UCHIDA, Hitoshi TANAKA and Takashi MAEKAWA, Plasma Fusion Res. 7, 1202005 (2012).