Statistical analysis to the SOL plasma fluctuation in JT-60U

Asakura, Nobuyuki; Ono, Noriyasu*; Tanaka, Hirohiko*; Kawashima, Hisato; Nakano, Tomohide

Characteristics of the fluctuations at three locations (Low-Field-Side midplane, X-point, and High-Field-Side SOLs) of the JT-60U SOL were investigated in L-mode and ELMy H-mode plasmas. Influence of their poloidal asymmetry at the LFS and HFS on the parallel plasma flow was investigated. For the L-mode, poloidal asymmetry in djs/js was enhanced at the LFS midplane (40-60%), while it was small (10-20%) at the HFS SOL and LFS X-point. On the other hand, djs/js was similar (20-30) for the ELMy H-mode. Statistical properties (Skewness) and their poloidal asymmetry were different in the ELMy H-mode and L-mode plasmas. In the ELMy H-mode, positive S (= 0.3-0.5) was seen near the separatrix. However, in the L-mode, larger S (=0.5-0.9) was observed at the LFS midplane, and it extended to the far SOL (r 10 cm). In-out asymmetry in the intermittent transport will contribute to produce the SOL flow pattern.