Behavior of edge plasma in STP-3M reversed field pinch

Abstract We have already reported that in an RFP plasma the energetic ions with the energy of about 3 keV are generated at magnetic reconnection. In this paper, the effect of these energetic ions on the behavior of the edge plasma is reported. In order to investigate the edge plasma, movable electrostatic probes scanning from the boundary of the core plasma to 122 mm outside are used. The energetic ions have a great influence on the behavior of the edge plasma. Even in the limiter shadow where energetic electrons concentrate, behavior of edge plasma greatly depended on the energetic ions.