Full Paper
IAEA-CN77
Contents Return Previous Page Next Page Index


Return To: Session EX9/TH6 - Energetic Particles
Prev Page: (EX9/3) Demonstration of Ripple Reduction by Ferritic Steel
Next Page: (TH6/1) Fast Particle Effects on the Internal Kink,


(EX9/4) Transition from Ion Root to Electron Root in NBI Heated Plasmas in LHD

K. Ida1), H. Funaba1), S. Kado2), K. Narihara1), K. Tanaka1), Y. Takeiri1), Y. Nakamura1), N. Ohyabu1), K. Yamazaki1), M. Yokoyama1), S. Murakami1), N. Ashikawa1), P. de Vries1),  M. Emoto1), M. Goto1), H. Idei1), K. Ikeda1), S. Inagaki1), N. Inoue1), M. Isobe1), K. Itoh1), O. Kaneko1), K. Kawahata1), K. Khlopenkov1), A. Komori1), S. Kubo1), R. Kumazawa1), Y. Liang3), S. Masuzaki1), T. Minami1), J. Miyazawa1), T. Morisaki1), S. Morita1), T. Mutoh1), S. Muto1), Y. Nagayama1), H. Nakanishi1), K. Nishimura1), N. Noda1), T. Notake4), T. Kobuchi1), S. Ohdachi1), K. Ohkubo1), Y. Oka1), M. Osakabe1), T. Ozaki1), R. O. Pavlichenko1), B. J. Peterson1), A. Sagara1), K. Saito4), S. Sakakibara1), R. Sakamoto1), H. Sanuki1), H. Sasao1), M. Sasao1), K. Sato1), M. Sato1), T. Seki1), T. Shimozuma1), M. Shoji1), H. Suzuki1), S. Sudo1), N. Tamura3), K. Toi1), T. Tokuzawa1), Y. Torii4), K. Tsumori1), T. Yamamoto1), H. Yamada1), I. Yamada1), S. Yamaguchi1), S. Yamamoto4), Y. Yoshimura1), K. Y. Watanabe1), T. Watari1), Y. Hamada1), O. Motojima1), M. Fujiwara1)
 
1) National Institute for Fusion Science, 322-6, Oroshi-cho, Toki, 509-5292, Japan
2) present address: High temperature Plasma Center, Univ. of Tokyo, Tokyo, 113-8656,Japan
3) Department of Fusion Science, School of Mathematical and Physical Science, Graduate University for Advanced Studies, Hayama, 240-0193, Japan
4) Department of Energy Engineering and Science, Nagoya University, 464-8603, Japan

Abstract.  Recent Large Helical Device (LHD) experiments revealed that the transition from ion root to electron root occurred for the first in neutral beam heated discharges, where there is no non-thermal electrons exist. The measured values of the radial electric field were found to be in qualitative agreement with those estimated by neoclassical theory. For the configuration with a magnetic axis of 3.75m, where the ion transport loss was comparable to the neoclassical ion loss, a clear reduction of ion thermal diffusivity was observed after the mode transition from ion root to electron root as predicted by neoclassical theory. On the other hand, for the inward shifted configuration ( Rax = 3.6m), where the neoclassical ion loss is reduced below the anomalous loss, no change in the ion thermal diffusivity was observed.

Read the full paper in PDF format.

IAEA 2001