Plasma and Fusion Research
Volume 9, 1302009 (2014)
Letters
- 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
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
Full Text
References
- [1] I. H. Hutchinson, Principles of Plasma Diagnostics (Cambridge Univ. Press, Cambridge) 2nd ed., p. 276 (2002).
- [2] S. Masamune et al., J. Phys. Soc. Jpn. 76, 123501 (2007).
- [3] R. Ikezoe et al., Plasma Phys. Control. Fusion 53, 025003 (2011).
- [4] R. Ikezoe et al., Plasma Phys. Control. Fusion 55, 015005 (2013).
- [5] R. Ikezoe et al., J. Phys. Soc. Jpn. 81, 115001 (2012).
- [6] A. Sanpei et al., J. Phys. Soc. Jpn. 78, 013501 (2009).
- [7] J.A. Reusch et al., Rev. Sci. Instrum. 79, 10E733 (2008).
- [8] H.D. Stephens et al., Rev. Sci. Instrum. 79, 10E734 (2008).
- [9] S. Hokin et al., Phys. Fluids B 3, 2241 (1991).
- [10] Y. Yagi et al., Phys. Plasmas 10, 2925 (2003).
- [11] M.D. Wyman et al., Phys. Plasmas 15, 010701 (2008).
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).