PARTICLE FUELING BY SHALLOW PELLET INJECTION IN JT-60U

Effects of the shallow pellet injection on the ELMy H-mode plasma have been investigated in JT-60U for single null open-divertor plasmas. Th e penetration depth of the pellet was 20-30% of the plasma minor radiu s from the outermost flux surface with NE heating power of 15-25 MW an d the plasma density of 1-2 x 10(19) m(-3). (1) A particle stream was generated transiently by the shallow pellet injection from the main pl asma to the divertor region without the degradation of the energy conf inement, and was accelerated by the enhanced ELM activity. (2) The tot al power on to the divertor plate (mainly to the inboard divertor regi on) increased just after the pellet injection by similar to 100% with similar to 60% rise of the maximum heat flux density. (3) The screenin g of the helium influx by the shallow pellet injection has been confir med from the delayed rise of the helium density in the main plasma, wh ich has been obtained by the helium gas puffing just after the pellet injection.