Plasma and Fusion Research

Volume 3, S1080 (2008)

Regular Articles

Efficient Heating at the Third-Harmonic Electron Cyclotron Resonance in the Large Helical Device

Takashi SHIMOZUMA, Shin KUBO, Hiroe IGAMI, Yasuo YOSHIMURA, Takashi NOTAKE¹⁾, Nikolai B. MARUSHCHENKO²⁾, Yurij TURKIN²⁾, Takashi MUTOH and the LHD Experimental Group

National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
1): University of Fukui, Research Center for Development of Far-Infrared Region, 3-9-1 Bunkyo, Fukui 910-8507, Japan
2): Max-Plank-Institut für Plasmaphysik, EURATOM-Association, Wendelsteinstr. 1, D-17491 Greifswald, Germany

(Received 16 November 2007 / Accepted 4 March 2008 / Published 1 August 2008)

Abstract

Efficient heating at the third-harmonic electron cyclotron resonance was attained by injection of millimeterwave power with 84 GHz frequency range at the magnetic field strength of 1 T in LHD. The electron temperature at the plasma center clearly increased, and the increment in the temperature reached 0.2-0.3 keV. The dependence of the power absorption rate on the antenna focal position was investigated experimentally, showing that the optimum position was located in the slightly high-field side of the resonance layer. Ray-tracing calculation was performed in the realistic three-dimensional magnetic configuration, and its results are compared with the experimental results.

Keywords

electron cyclotron resonance heating, gyrotron, harmonic resonance, quasi optical antenna, ray tracing

DOI: 10.1585/pfr.3.S1080

Full Text

PDF format (972Kbytes) PDF Download

References

[1] U. Gasparino, H. Idei, S. Kubo et al., Nucl. Fusion 38, 223 (1998).
[2] N. Yanagi, S. Morimoto, M. Sato et al., Nucl. Fusion 31, 261 (1991).
[3] S. Alberti, T.P. Goodman, M.A. Henderson et al., Nucl. Fusion 42, 42 (2002).
[4] G. Arnoux et al., Plasma Phys. Control. Fusion 47, 295 (2005).
[5] S. Alberti et al., Nucl. Fusion 45, 1224 (2005).
[6] H.P. Laqua, V. Erckmann, R. Brakel et al., 15th International Stellarator Workshop, Madrid,3-7, October 2005, IT-20.
[7] T. Shimozuma, H. Idei et al., 27th European Physical Society Conference on Controlled Fusion and Plasma Physics, Budapest, Hungary, June 12-16, 2000, P4.019.
[8] S. Kubo, T. Shimozuma et al., Plasma Phys. Control. Fusion 47, A81 (2005).
[9] N.B. Marushchenko, V. Erckmann, H. Maaßberg, Yu. Turkin, 34th European Physical Society Conference on Plasma Physics, Warsaw, Poland, July 2-6, 2007, P5.129.
[10] N.B. Marushchenko et al., Plasma Fusion Res. 2, S1129 (2007).

This paper may be cited as follows:

Takashi SHIMOZUMA, Shin KUBO, Hiroe IGAMI, Yasuo YOSHIMURA, Takashi NOTAKE, Nikolai B. MARUSHCHENKO, Yurij TURKIN, Takashi MUTOH and the LHD Experimental Group, Plasma Fusion Res. 3, S1080 (2008).