RF Experiments on TST-2

POSTER

Abstract

RF experiments were performed on the TST-2 spherical tokamak (R= 0.38 m, a = 0.25 m, B$_{t}$ = 0.3 T, I$_{p}$ = 0.1 MA) with up to 5 kW of power at 2.45 GHz and up to 400 kW of power at 21 MHz. In HHFW electron heating of inductively produced plasmas, parametric decay instability was often observed. The spatial distribution measured by RF magnetic probes located at different toroidal locations indicated wave propagation effects as well as nonlinear effects. Spontaneous formation of the ST configuration was studied. Sustainment of the ST configuration was accomplished by low frequency (21 MHz) RF power alone for the first time. LHCD and I$_{p}$ ramp-up experiments are in preparation using up to 400 kW of power at 200 MHz. This experiment will be carried out at B$_{t}$ = 0.3 T, and the density of the EC produced plasma will be kept low during I$_{p}$ ramp-up by LHCD. Status of preparation and results of calculations will be presented.

Authors

  • Yuichi Takase

    University of Tokyo, The University of Tokyo, Univ. Tokyo

  • Akira Ejiri

    University of Tokyo, Univ. Tokyo, The University of Tokyo

  • Yoshihiko Nagashima

    University of Tokyo, Univ. Tokyo, The University of Tokyo

  • Osamu Watanabe

    University of Tokyo, The University of Tokyo

  • Bung Il An

    University of Tokyo, Univ. Tokyo, The University of Tokyo, MIT

  • Kentaro Hanashima

    University of Tokyo, The University of Tokyo

  • Hiroyuki Hayashi

    University of Tokyo, The University of Tokyo

  • Junichi Hiratsuka

    University of Tokyo, The University of Tokyo

  • Hidetoshi Kakuda

    University of Tokyo, The University of Tokyo

  • Hiroaki Kobayashi

    University of Tokyo, Univ. Tokyo, The University of Tokyo

  • Hiroki Kurashina

    University of Tokyo, The University of Tokyo

  • Hazuki Matsuzawa

    The University of Tokyo, University of Tokyo

  • Takuya Oosako

    Univ. Tokyo, The University of Tokyo, University of Tokyo

  • Takuya Sakamoto

    University of Tokyo, The University of Tokyo

  • Takuma Wakatsuki

    University of Tokyo, Univ. Tokyo, The University of Tokyo

  • Kotaro Yamada

    University of Tokyo, The University of Tokyo

  • Takashi Yamaguchi

    University of Tokyo, The University of Tokyo

  • P.T. Bonoli

    Massachusetts Institute of Technology, MIT, MIT Plasma Science and Fusion Center, PSFC-MIT, MIT-PSFC

  • J. Wright

    MIT, PSFC-MIT, MIT Plasma Science and Fusion Center, MIT-PSFC