Density Collapse in Improved Confinement Mode on Tohoku University Heliac
نویسندگان
چکیده
The density collapse was observed in the improved confinement mode sustained by the hot cathode biasing in Tohoku University Heliac (TU-Heliac). The density profiles showed the steep gradient around the core plasma region before the collapse. The steep density profile collapsed accompanied with the bursting high frequency fluctuation (100 < f < 500 kHz), which had m = 2 ~ 3 poloidal mode number and the frequency agreed well with the E x B plasma rotating frequency. After the collapse the steep gradient in the density profile disappeared and the density outside the core region increased in the level consistent with the decrease of the core
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