Investigation of Electromagnetic-Flute-Mode Instability in a High-Beta Z-Pinch Plasma

• Published in: IEEE transactions on plasma science Vol. 34; no. 5; pp. 2239 - 2246
• Main Authors: Sotnikov, V.I., Ivanov, V.V., Cowan, T.E., Leboeuf, J.-N.G., Oliver, B.V., Coverdale, C.A., Jones, B.M., Deeney, C., Mehlhorn, T.A., Sarkisov, G.S., LePell, P.D.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-10-2006; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Cables; Comparative analysis; Diagnostics; Electromagnetism; Flute modes; Laboratories; Magnetic fields; nonlinear cascades; Optical arrays; Oscillators; Plasma; Plasma applications; Plasma density; Plasma diagnostics; Plasma sources; Plasma temperature; Plasma waves; turbulence; Wire; Nevada
• ISSN: 0093-3813; 1939-9375
• DOI: 10.1109/TPS.2006.878373

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