In JT-60U ELMy H-mode plasmas, the width of the edge pedestal ped observed in the ion temperature profiles is two to three times larger than that in the edge localized modes (ELM)-free plasmas. At high triangularity, ped reaches 8-15 cm (9-16% of the minor radius) at the plasma current of 1 MA. In the high triangularity ELMy H-mode, the ion temperature at the pedestal shoulder and ped can increase gradually with a time constant of ~2-3 s, which is longer than the global energy confinement time by one order of magnitude. In addition, pressure gradient in the pedestal layer increases simultaneously. The width ped scales linearly with the poloidal gyro radius of thermal ions pi at a fixed peripheral safety factor q95 (ped~3-4pi at q95 = 3-4), and has a weak dependence on q95; ped~5piq95-0.3. The shrinkage of ped observed at a high density can be explained by a decrease in the edge ion temperature with respect to a decrease in pi. At a higher q95(~6) a further increase in ped was observed after the disappearance of ELMs.
ELM control strategies and tools: status and potential for ITER