Plasma and Fusion Research

Volume 7, 2402052 (2012)

Regular Articles

Design and Initial Result of Time-Resolved Vertical Soft X-Ray Imaging System in Low-A RFP

Akio SANPEI, Kensuke OKI, Daisuke FUKAHORI, Kazuaki DEGUCHI, Seiya NAKAKI, Kanae NISHIMURA, Haruhiko HIMURA, Sadao MASAMUNE, Satoshi OHDACHI¹⁾, Nobuhiro NISHINO²⁾ and Takumi ONCHI³⁾

: Kyoto Institute of Technology, Kyoto 606-8585, Japan
1): National Institute for Fusion Science, Toki 509-5292, Japan
2): Hiroshima University, Hiroshima 739-8527, Japan
3): University of Saskatchewan, Saskatchewan, Canada

(Received 9 December 2011 / Accepted 16 March 2012 / Published 07 June 2012)

Abstract

A time-resolved vertical soft X-ray (SXR) imaging system was constructed. To identify the structure of the magnetic island using the obtained SXR images, we calculated the two-dimensional (2-D) image expected from low-aspect-ratio (low-A) reversed field pinch (RFP) plasmas. The 2-D image was found to reflect the change in the radiation power caused by the magnetic island. A preliminary experimental result in which we observed vertical SXR images from the quasi-periodic quasi-single helicity (QSH) state in low-A RFP plasmas is presented. We successfully obtained the time evolution of SXR images from the vertical port. By comparing the observed images with simulated images, we found that the evolution of the experimental SXR image suggests a rotating helical configuration.

Keywords

RFP, soft X-ray (SXR), imaging, magnetic island, high-speed camera

DOI: 10.1585/pfr.7.2402052

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This paper may be cited as follows:

Akio SANPEI, Kensuke OKI, Daisuke FUKAHORI, Kazuaki DEGUCHI, Seiya NAKAKI, Kanae NISHIMURA, Haruhiko HIMURA, Sadao MASAMUNE, Satoshi OHDACHI, Nobuhiro NISHINO and Takumi ONCHI, Plasma Fusion Res. 7, 2402052 (2012).