Edge Ohmic Heating Experiment on HT-6M Tokamak

An improved ohmic confinement has been achieved on HT-6M tokamak after application of edge ohmic heating pulse which makes plasma current rapidly ramp up (0.4 ms) in a ramp rate of 12 MA/s. The improved ohmic confinement phase is characterized by (a) energy and particle confinement time increase, (b) non-symmetric increased density n_e, (c) reduced H_α radiation, (d) increased T_e and steeper T_e, n_e profile at the edge. The results from soft x-ray sawteeth inversion radius and β_p +l_i/2 implied the anomalous current penetration.