Active Trajectory Control for a Heavy Ion Beam Probe on the Compact Helical System

A 200keV heavy ion beam probe (HIBP) on the Compact Helical System torsatron/heliotron uses a newly proposed method [Review of Scientific Instruments 63 3694 (1992)] in order to control cornplicated beam trajectories in non-axisymmetrical devices. As a result, the HIBP has successfully measured potential profiles of the toroidal helical plasma. The article will describe the results of the potential profile measurements, together with the HIBP hardware system and procedures to realize the method