Measurement of Plasma-Induced Arcs in Tokamaks

Plasma-sustained arcs have been studied that occurred at probes inserted into the tokamaks TM1-MH (Prague) and Tuman 3 (Leningrad). Arc ignition was correlated with spikes of the plasma potential with respect to the wall. From the electrkal characteristks of the arcs it is concluded that the arc channel consists of a thin filament, having rather high inductances, and consisting sometimes of several turns around the torus along the magnetic-field lines.