Measurements of HHFW profile in UTST

POSTER

Abstract

HHFW (high-harmonic fast wave, f = 21 MHz) experiments were performed on the UTST spherical tokamak (R= 0.38 m, a = 0.25 m, B$_{t}$ = 0.1 T, I$_{p}$ = 0.1 MA) [T. Yamada, this session]. The HHFW antenna consists of two poloidal current straps separated in the toroidal direction. The spatial profile of the HHFW field was measured by a 2-dimensional array of magnetic probes inserted into the plasma 45\r{ } away from the antenna toroidally. 40 channels of RF data can be acquired simultaneously by fast digitizers (1 GHz sampling frequency) out of 81 probes. A comparison of wave fields measured with out-of-phase two-strap excitation (high parallel wavenumbers) and with single strap excitation (low parallel wavenumbers) indicate higher RF fields inside the plasma for the same input power. The experimental data will be compared with results of wave field calculation.

Authors

  • Takuma Wakatsuki

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

  • Takuya Oosako

    University of Tokyo

  • Hiroaki Kobayashi

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

  • T. Yamada

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

  • Bung Il An

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

  • R. Imazawa

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

  • K. Abe

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

  • Akira Ejiri

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

  • Kentaro Hanashima

    University of Tokyo, The University of Tokyo

  • Hiroyuki Hayashi

    University of Tokyo, The University of Tokyo

  • R. Hihara

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

  • Junichi Hiratsuka

    University of Tokyo, The University of Tokyo

  • M. Inomoto

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

  • Hidetoshi Kakuda

    University of Tokyo, The University of Tokyo

  • S. Kamio

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

  • Hiroki Kurashina

    University of Tokyo, The University of Tokyo

  • Yoshihiko Nagashima

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

  • Yasushi Ono

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

  • Takuya Sakamoto

    University of Tokyo, The University of Tokyo

  • M. Sakumura

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

  • Q.H. Cao

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

  • Yuichi Takase

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

  • Osamu Watanabe

    University of Tokyo, The University of Tokyo

  • Takashi Yamaguchi

    University of Tokyo, The University of Tokyo

  • Kotaro Yamada

    University of Tokyo, The University of Tokyo