[Table of Contents]

Plasma and Fusion Research

Volume 9, 1302009 (2014)

Letters


Electron Temperature Measurement by Thomson Scattering in a Low-Aspect-Ratio RFP RELAX
Ryota UEBA, Sadao MASAMUNE, Akio SANPEI, Kosuke UCHIYAMA, Hiroyuki TANAKA, Kanae NISHIMURA, Go ISHII, Ryosuke KODERA, Haruhiko HIMURA, Daniel J. Den HARTOG1) and Haruhisa KOGUCHI2)
Kyoto Institute of Technology, Kyoto 606-8585, Japan
1)
University of Wisconsin-Madison, Madison WI 53706-1302, USA
2)
National Institute for Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan
(Received 8 September 2013 / Accepted 2 January 2014 / Published 28 February 2014)

Abstract

A Thomson scattering diagnostic system has been developed for measuring electron temperatures in low-aspect-ratio reversed-field pinch (RFP) plasmas in REversed-field pinch of Low Aspect ratio eXperiment (RELAX). In the range of plasma currents Ip = 50 - 80 kA, the central electron temperature was around 100 eV and, showed a weakly increasing trend as Ip increases. To estimate the central electron pressure pe0, a density calibration was performed from simultaneous measurements with a 104-GHz microwave interferometer. The maximum pe0 increased with Ip up to ∼ 70 kA to preserve the approximate relation pe0/Bθa2 ∼ constant, where Bθa is the edge poloidal field. In the higher current region, pe0 tended to saturate, which may be improved by optimizing minute control of equilibrium in the higher current region.


Keywords

reversed-field pinch, Thomson scattering diagnostic, electron temperature, high-β plasma, RELAX

DOI: 10.1585/pfr.9.1302009


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This paper may be cited as follows:

Ryota UEBA, Sadao MASAMUNE, Akio SANPEI, Kosuke UCHIYAMA, Hiroyuki TANAKA, Kanae NISHIMURA, Go ISHII, Ryosuke KODERA, Haruhiko HIMURA, Daniel J. Den HARTOG and Haruhisa KOGUCHI, Plasma Fusion Res. 9, 1302009 (2014).