Plasma and Fusion Research

Volume 11, 2402074 (2016)

Regular Articles

Measurement of Tokamak Plasma with the External Helical Field Using a High-Speed Camera in TOKASTAR-2
Tatsuya SAKITO, Hideki ARIMOTO, Takaaki FUJITA, Atsushi OKAMOTO, Yusuke SHIMOOKA, Hiromasa ITOU, Ryoichi SUGIOKA, Kenji MURAOKA, Kouhei YASUDA and Ryoma YOKOYAMA
Department of Energy Engineering and Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
(Received 30 November 2015 / Accepted 23 March 2016 / Published 17 May 2016)


The high-speed camera was used to evaluate the position of the plasma in TOKASTAR-2. A plane mirror was installed in the vacuum vessel to expand the field of view and get the image in the whole region between inner and outer walls. The images were taken at 86400 FPS with 256 × 128 pixels (20 μm / pixel) per frame in the tokamak discharge with and without the external helical field. Under the condition of the weak vertical field, the plasma position control was improved by the external helical field. The outward plasma displacement was suppressed and the plasma was located stably in contact with the inner legs of the TF coils.


high-speed camera, emission intensity, tokamak discharge, helical field application, TOKASTAR, tokamak-stellarator hybrid confinement

DOI: 10.1585/pfr.11.2402074


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