Study of core plasma rotation characteristics of RF-heated H-mode discharges on experimental advanced superconducting tokamak

RF-heated H-mode plasmas are readily achieved with lower hybrid current drive and ICRF heating on experimental advanced superconducting tokamak (EAST). Characteristics of H-mode plasma rotation are studied, including the behaviors for non-stationary and stationary H-mode discharges. Experimental results indicate that substantial co-current core rotation increment is observed at L-H transition.

For non-stationary discharges with multiple L-H transitions, central plasma rotation varies as the plasma enters and exits the H-mode phase. Rotation increase over L-H transition is linearly correlated with plasma stored energy for both edge localized mode (ELM)-free phases and phases with type-III ELMs. For stationary H-mode discharges with type-III ELMs, core plasma rotation profile is elevated and remains stable during the H-mode phase, although the occurrence of ELMs tends to slow down the core rotation, especially for type-I ELMs where the entire core profiles are affected.