Improvement of Confinement in Auxiliary-Heated (ICRF) Divertor Discharges by Pellet Injection

摘要

An improvement of plasma confinement by pellet injection was investigated in ion cyclotron range of frequency (ICRF) wave heated plasmas with a single null divertor configuration on JFT-2M. Pellets were injected into the L- and H-modes of the ICRF heated plasmas. Global energy confinement time (tau/sub E/) was drastically improved in both modes. Such an improvement by the pellet fueling in the H-mode could not be achieved in the neutral beam (NB) heated plasmas. Line averaged electron density of 6 x 10/sup 19/ m/sup -3/ ( delta n-bar/sub e/ = 3 x 10/sup 19/ m/sup -3/) obtained by the pellet fueling was maintained for about 100 ms, so it is considered that particle confinement is improved. Radiation loss was not large in the pellet fueled discharges. (ERA citation 13:017893)