Investigation of Magnetic Fields in Wire Arrays and X-Pinches at the 1-MA Zebra Accelerator

Summary form only given. A Faraday rotation diagnostic was developed at the Nevada Terawatt Facility (NTF) for investigation of magnetic fields in plasma from 1-MA wire arrays and X-pinches. Optical diagnostics at the NTF includes a four-channel polaro-interferometer and four-frame shadowgraphy. The polaro-interferometer consists of identical shadow and Faraday channels, shearing air-wedge interferometer, and schlieren channel. Different regimes of the wire array implosion were observed in Al and Cu wire arrays. A current in the plasma column of the Al wire array was found by the Faraday rotation diagnostic. Bubble-like magneto-active objects were observed for the first time in the plasma column of the wire array. Interferometry showed that the plasma column consists of strongly turbulent plasma. Shadowgraphy shows imprints of streams on the surface of the precursor. The five shadow frames per shot presents details of plasma evolution in the wire array. Transfer of current to the axis was investigated in Al, W and Cu wire arrays. In the X-pinch the Faraday rotation effect shows the current in the waist and alternative paths of current through the peripheral plasma. The multi frame shadowgraphy presents the dynamics of X-pinch plasma