[Table of Contents]

Plasma and Fusion Research

Volume 7, 2402056 (2012)

Regular Articles

Identification of MHD Mode Structure using ECE and SX Measurements
Hayato TSUCHIYA, Yuuki TAKEMURA1), Yoshio NAGAYAMA, Daisuke KUWAHARA2), Kiyomasa WATANABE, Satoru SAKAKIBARA and LHD Experimental Group
National Institute for Fusion Science, Toki 509-5292, Japan
1)
The Graduate University for Advanced Studies, Toki 509-5292, Japan
2)
Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
(Received 9 December 2011 / Accepted 4 March 2012 / Published 26 July 2012)

Abstract

This study reports characteristics of the interchange mode-like magnetohydrodynamic (MHD) mode through comparisons between fluctuations measured by electron cyclotron emission (ECE) and Soft X-ray (SX) in the Large Helical Device (LHD). The MHD mode, whose frequency is 0.74 to 2.7 kHz, is enhanced near ρ = 0.8, ι = 1. Te fluctuation data measured by ECE can identify the mode width by using the displacement amplitude profile whereas SX data cannot show the structure clearly. Furthermore the dependence of the width and amplitude on the pressure gradient is shown using Te fluctuations.

Keywords

MHD low-order mode, LHD, electron cyclotron emission, soft x-ray, displacement amplitude

DOI: 10.1585/pfr.7.2402056

Full Text

PDF format (2.2Mbytes) PDF Download

References

  • [1] O. Motojima et al., Nucl. Fusion 40, 599 (2000).
  • [2] K.Y. Watanabe, S. Masamune, Y. Takemura et al., Phys. Plasmas 18, 056119 (2011).
  • [3] J.H. Harris, M. Murakami, B.A. Carreras, J.D. Bell et al., Phys. Rev. Lett. 63, 1249 (1989).
  • [4] S. Masamune, 23rd IAEA Fusion Energy Conference, Daejon, Republic of Korea, EXS/P5-11.
  • [5] H. Tsuchiya, Y. Nagayama, K. Kawahata, S. Inagaki, S. Kubo and LHD Experiment Group, Plasma Fusion Res. 6, 2402114 (2011).
  • [6] S. Sakakibara, H. Yamada, K. Yamazaki, K.Y. Watanabe et al., Fusion Eng. Des. 34-35, 707 (1997).
  • [7] S. Ohdachi, F. Watanabe, S. Yamamoto, K. Toi, C. Suzuki, K. Ida, S. Muto and LHD Experiment Group, Fusion Sci. Technol. 58, 418 (2010).

This paper may be cited as follows:

Hayato TSUCHIYA, Yuuki TAKEMURA, Yoshio NAGAYAMA, Daisuke KUWAHARA, Kiyomasa WATANABE, Satoru SAKAKIBARA and LHD Experimental Group, Plasma Fusion Res. 7, 2402056 (2012).