Measurement of peripheral plasma turbulence using a fast camera in Heliotron J

作者：Nishino N^*; Mizuuchi T; Kobayashi S; Nagasaki K; Okada H; Sano F; Yamamoto S; Kondo K

来源：Journal of Nuclear Materials, 2009, 390-91: 432-435.

DOI：10.1016/j.jnucmat.2009.01.119

Using a fast camera with a tangential view, filamentary structure in a peripheral region was observed during L and H-mode, and the apparent motion of filamentary structure across the magnetic Held was also observed. In the L-mode the cross-field scale of the filamentary structure was smaller than that in the H-mode. In the L-mode the apparent motion was counterclockwise in a camera view. During L-H transition the apparent motion was stopped, and in the H-mode the apparent motion changed direction, and the speed of the apparent motion nearly doubled. If this apparent motion was due to Er x B drift, Er should be positive in the L-mode and E, should be negative in the H-mode. To get the density threshold for the H-mode a directional gas puff was used, and it was found that the dithering phase appeared after low frequency MHD activity (1-2 kHz), even though the density was higher than that of the H-mode threshold.

• 出版日期2009-6-15