IMPROVED CONFINEMENT BY EDGE MULTIPULSE TURBULENT HEATING ON HT-6M TOKAMAK

In the recent experiment on HT-6M tokamak, an improved ohmic confineme nt phase has been observed after application of the edge multi-pulse t urbulent heating, and variance of plasma current Delta I-p/I-p is abou t 14-20%. The improved edge plasma confinement phase is characterized by (a) increased average electron density (N) over bar(e) and electron temperature T-e; (b) reduced H-alpha radiation from the edge; (c) ste eper density and temperature profiles at the edge; (d) a more negative radial electric field over a region of similar to 5 mm deep inside th e limiter; (e) a deeper electrostatic potential well at the edge; (f) reduced magnetic fluctuations at the edge. PACS: 52.55.Fa, 52.50.Gj.