Plasma flows and fluctuations with magnetic islands in the edge of J-TEXT tokamak
نویسندگان
چکیده
The first comprehensive measurements of plasma flows and fluctuations nearby static magnetic islands driven by resonant magnetic perturbations (RMPs) are presented. These experiments were performed using multiple Langmuir probe arrays in the edge plasmas of the J-TEXT tokamak. The effects of controlled variations of the island size and location are explored. This study aims to understand the interaction between turbulence and magnetic islands, and to elucidate magnetic island effects on edge turbulence and flow intensity profiles, edge electric fields, and thus confinement regime transitions. Turbulence and low frequency flows (LFFs) all drop inside the magnetic island, but increase at its boundary, as island width increases. The geodesic acoustic mode (GAM) is damped in most of the edge area with magnetic islands. The sign of the radial electric field changes from negative to positive within
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