Observation of beam-induced toroidal plasma currents and neoclassical current under neutral beam injection heating in Heliotron E

Abstract
The authors report the observation of beam-induced toroidal plasma currents (<or=2 kA) excited by the neutral beams of 1 MW in Heliotron E. The induced plasma current is measured as a function of neutral beam power in both co-injection and counter-injection. The observed plasma currents are explained by the compound phenomena of the beam-induced (Ohkawa) current plus the neoclassical ('bootstrap') current.