Plasma and Fusion Research

Volume 15, 1202023 (2020)

Rapid Communications

Development of a Compact Hard X-Ray Camera on the TST-2 Spherical Tokamak
Akira EJIRI, Yuki AOI, Hibiki YAMAZAKI, Naoto TSUJII, Yuichi TAKASE, Osamu WATANABE, Yongtae KO, James H.P. RICE, Yi PENG, Kotaro IWASAKI, Kyohei MATSUZAKI, Yuki OSAWA and Yasuo YOSHIMURA1)
The University of Tokyo, Kashiwa 277-8561, Japan
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 26 February 2020 / Accepted 15 March 2020 / Published 11 May 2020)


A compact hard X-ray camera has been developed to study the behavior of fast electrons accelerated by lower hybrid waves in the TST-2 spherical tokamak. The camera consists of a pinhole made of tungsten alloy, a thin resin window, a thin LYSO scintillator disk, 5 fiber optic light guides and 5 photomultiplier tubes and shields. The camera is installed on a tangential port, and two-dimensional images are obtained by rotating the system around the axis of the port on a shot by shot basis. The typical energy range is 10 - 250 keV, and the energy resolution is about 100% (FWHM) at 100 keV. The measured images of a lower hybrid wave driven plasma show bright region at the inboard side (i.e., high field side).


hard X-ray measurement, pinhole camera, LYSO scintillator, spherical tokamak, lower hybrid wave

DOI: 10.1585/pfr.15.1202023


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