Electron Current Measurement of Helical Nonneutral Plasmas for Investigating Plasma Disruption Observed in CHS Experiments

Abstract

A nonneutral plasma confined on helical magnetic surfaces exhibits instability, although it is theoretically stable. In order to investigate the disruptive phenomenon in detail, electron particle flow into a probe tip is carefully measured inside the magnetic surfaces. Preliminary results indicate that the observed disruption is first to occur near the top of the plasma, and then, seems to propagate toward the center of the plasma.