Pedestal characteristics and extended high-βp ELMy H-mode regime in JT-60U

With the high-field-side multiple pellet injection into high-triangularity high-βp type I ELMy H-mode discharges, JT-60U has extended the density range with a favourable integrated performance. The pellet injected discharge has a high pedestal pressure compared with the gas fuelled discharges, and the pedestal temperature does not decrease even at high pedestal density. At high triangularity, the pedestal βp and the edge α-parameter increase with increasing total βp. Possible linkage among pedestal and core parameters has been proposed based on a variety of JT-60U experiments. Grassy ELMy discharges have been achieved at the low safety factor regime q95<4 for the first time in JT-60U with high triangularity (~0.6). The full non-inductive operation has been demonstrated with grassy ELMs.