Toroidal rotation braking induced by n=4 RMP in EAST

An obvious toroidal plasma rotation braking effect was observed during the application of n=4 resonant magnetic perturbation (RMP) in EAST, which shows a global profile and a peak located near the plasma center. Neoclassical toroidal viscosity (NTV) theory is one of an effective explanation in magnetic braking. The variation of toroidal angular velocity reproduced with neoclassical toroidal viscosity (NTV) torque shows good qualitative agreement with the measured rotation variation profile in most radial regions, and the difference is 1~2 times.