Inductive Magnetic Probe Diagnostics in a Plasma

摘要

Inductive magnetic probes were studied, designed, constructed, calibrated and used at the Plasma Study Facility. The probes were built for three specific purposes: to measure current, radial shock waves and Alfven waves in a fast Theta Pinch; to measure the parameters of shock fronts with short rise times produced by laser exploding of metal fibers; and to observe instabilities in a steady state plasma. Theta Pinch current measurements gave a current of 110 KAmps with the Theta Pinch operating with the capacitors charged to 13KV of 25KV maximum. The ringing frequency of the Theta Pinch was measured as 179 KHz. On calibration, the shock front probes showed a first resonance at 40 MHz which is comparable to probe characteristics found in recent literature. The instability probes gave information which agreed with previous descriptions of instabilities based on optical and Langmuir probe diagnostics. (Author)