Simulation study on reversed field pinch plasmas with rf current drive

We study the relaxation phenomena of the reversed field pinch (RFP) plasma with a radio-frequency (rf) current drive. We develop the magnetohydrodynamic code, in which the effect of the rf current drive is included in the induction equation as an external electric field obtained from the ray tracing of the fast magnetosonic wave. As the results of simulations, we observe that the rf current drive can effectively reduce the disturbance due to the kink mode instabilities and it may sustain the reversed field without the MHD relaxation dynamics. These results suggest that the rf current drive is a prospective method to enable a quiet sustainment of the RFP configuration. (author)