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A Faraday rotation diagnostic was applied for the investigation of magnetic fields in plasma of 1-MA wire arrays and X-pinches. Laser-probing diagnostics at the Zebra generator include a four-channel polarointerferometer and a four-frame shadowgraphy. The Faraday rotation diagnostic consists of shadow and Faraday channels, shearing air-wedge interferometer, and an additional schlieren channel. The implosion dynamics of the wire arrays were studied. A current in the plasma column of AI low-wire number arrays was found by the Faraday rotation diagnostic. Optical diagnostics showed a turbulent plasma and bubblelike objects in the plasma column of Al wire arrays. The Faraday rotation diagnostic demonstrated a complicated structure of magnetic fields in X-pinch plasma. Index Terms--Faraday effect, laser probing, plasma turbulence, wire-array Z-pinch, Z-pinch plasmas.

Recent experiments (laser multiframe shadowgraphy and Faraday rotation diagnostics) with Al imploding wire arrays in the 1-MA 'Zebra' accelerator at the Nevada Terawatt Facility have demonstrated that a significant amount of current is going through the central region of the high-beta precursor plasma. With time, the perturbations develop both long scale structures and short-wavelength oscillations in the directions perpendicular to the magnetic field. The most likely candidate for the observed phenomena is the flutelike electromagnetic modes. These are excited in the current-carrying high-beta inhomogeneous precursor plasma due to the curvature of the magnetic field produced by the current. These modes may also play a role in the stagnation phase of Z-pinches. In this paper, nonlinear equations describing electromagnetic-flute-type oscillations in the high-beta precursor plasma are derived, and the linear stage of instability of these waves is examined. A comparison with the experimental results is performed as well. Index Terms--Flute modes, nonlinear cascades, turbulence, Z-pinch plasmas.

Time-integrated and laser-probing imaging diagnostics provide insight about the physics of wire explosions. Most interesting results have been obtained for refractory metal wires. In these cases, imaging diagnostics provide insight into the structure and value of the energy deposited into metal. Index Terms--Fast exploding wires, shadowgram, time-integrated imaging.