-
Author(s):
A. Fujisawa, H. Iguchi, S. Lee, K. Tanaka, T. Minami, Y. Yoshimura, M. Osakabe, K. Matsuoka, S. Okamura, H. Idei, S. Kubo, S. Ohdachi, S. Morita, R. Akiyama, K. Toi, H. Sanuki, K. Itoh, K. Ida, A. Shimizu, S. Takagi, C. Takahashi, M. Kojima, S. Hidekuma, S. Nishimura, M. Isobe, A. Ejiri, N. Inoue, R. Sakamoto, Y. Hamada and M. Fujiwara
-
Title:
Dynamic Behavior Associated with Electric Field Transitions in CHS Heliotron/Torsatron
Date of publication:
Oct. 1998
-
Key words:
IAEA, fusion energy conference, Yokohama
-
Abstract:
A new kind of oscillatory steady state is discovered in observation of potential with a heavy ion beam probe in Compact Helical System Heliotron/Torsatron. Bulk plasma parameters, such as electron temperature and density profile, change being synchronized with the pulsation of potential. The phenomenon can be regarded as successive transitions between two bifurcative states of the plasma. The pulsation can be self-sustained and create a dynamic steady state in low density plasma with electron cyclotron heating. The cause of phenomenon is associated with the bifurcation nature of radial electric field, that is inherent with toroidal heiical plasmas. This paper presents two examples of the phenomenon in different density regimes. Dependence of pulsation characteristics on several parameters is described. The bifurcation property predicted by a neoclassical theory is presented for comparison with the experimental observations.
-
|
