JT-60U high power heating experiments

Shimada, Michiya; JT-60 Team

Heating experiments have been carried out in JT-60U with plasma currents of up to 4 MA, toroidal fields of up to 4.2 T and a neutral beam heating power of 30 MW. Carbon fibre composite divertor plates with good alignment and bevelled edges provide an excellent power handling capability: no carbon burst has been observed during 5 s heating pulses at 20 MW. An H-mode was observed at the high toroidal field of 4.2 T. A confinement improvement factor of up to 1.6 over L-mode scaling has been obtained during the continuous ELMy phase at 4.2 T, for 2.7 MA and an injection power of 25 MW.