A study of the magnetized coaxial gun operation driving a Spheromak in the presence of a rotating n=1 asymmetry

Summary form only given. In the Sustained Spheromak Physics Experiment (SSPX), a large toroidal n=1 magnetic mode is observed within the coaxial gun (/spl delta/B/B/spl ap/15-20%). The fraction of gun flux used for helicity injection is accurately determined using internal probes and an asymmetric rigid rotor model. Current and field distributions in the gun show plasma there is neither relaxed nor complexity force-free A j/sub /spl perp// produces a torque opposite then n=1 rotation direction. This is interpreted as a result of line tying acting to counter any motion associated with the n=1 mode.