Fluctuation and transport reduction in a reversed field pinch by inductive poloidal current drive

Abstract

An auxiliary poloidal inductive electric field applied to a reserved field pinch plasma reduces the current density gradient, slows the growth of m=1 tearing fluctuations, suppresses their associated sawteeth, and doubles the energy confinement time. Small sawteeth occur in the improved state but with m=0 precursors. By requiring a change of toroidal flux embedding the plasma, inductive poloidal current profile drive is transient, but the improvement encourges the program of reversed field pinch transport suppression using current profile control.