Observation of a Complex Multistage Transition in the JT-60U $H$-mode Edge

Observation of a Complex Multistage Transition in the JT-60U $H$ -mode Edge

K. Kamiya, K. Ida, Y. Sakamoto, G. Matsunaga, A. Kojima, H. Urano, N. Oyama, Y. Koide, and Y. Kamada (JT-60 Team)

Phys. Rev. Lett. 105, 045004 – Published 22 July 2010

Abstract

A complex multistage transition of the edge radial electric field is observed in JT-60U $H$ -mode phase without edge localized mode. An interesting feature is that the poloidal rotation velocity of the carbon impurity ions changes in the later $H$ -phase without a comparable change in the main ion pressure gradient, indicating a change in the parallel momentum (and particle) balance channel.