(EX/7-1Rb) Plasma Rotation and Wall effects on Resistive Wall Mode in JT-60U

M. Takechi1), G. Matsunaga1), T. Ozeki1), N. Aiba1), G. Kurita1), A. Isayama1), Y. Koide1), Y. Sakamoto1), T. Fujita1), Y. Kamada1), JT-60 Team1)
 
1) Japan Atomic Energy Agency, Naka, Japan

Abstract.  This paper reports the exploration of the RWM onset using co-, near zero, counter plasma rotation profiles in JT-60U. This is the first experimental result which demonstrates the dependence of critical RWM onset of plasma rotation and beta on initial plasma rotation with the variation of the angular momentum input and without magnetic braking. In the JT-60U with newly ferretic wall installed, it is possible to produce high beta plasma tightly coupled with the wall ( b/a≈1.2) above βN > βN.no-walllimit. In near-zero plasma rotation, the RWM started to grow at βNβN.no-walllimit and with finite plasma rotation, the plasma pressure survives up to much higher βN level than that with small rotation. The observed critical beta onset βc and the RWM growth rate γRWM are discussed along with theoretical predictions using experimentally observed q-, pressure-, and rotation profiles.

Full paper and slides available (PDF)