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arXiv · 1712.05829

Experimental investigation of coaxial-gun-formed plasmas injected into a background transverse magnetic field or plasma

Yue Zhang·Dustin M. Fisher·Mark Gilmore·Scott C. Hsu·Alan G. Lynn
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Abstract

Injection of coaxial-gun-formed magnetized plasmas into a background transverse vacuum magnetic field or into a background magnetized plasma has been studied in the helicon-cathode (HelCat) linear plasma device at the University of New Mexico [M. Gilmore et al., J. Plasma Phys.81, 345810104 (2015)]. Magnetized plasma jet launched into a background transverse magnetic field shows emergent kink stabilization of the jet due to the formation of a sheared flow in the jet above the kink-stabilization threshold $0.1kV_A$ [Y. Zhang et al., Phys. Plasmas 24, 110702 (2017)]. Injection of a spheromak-like plasma into a transverse background magnetic field led to the observation of finger-like structures on the side with a stronger magnetic field null between the spheromak and background field. The finger-like structures are consistent with magneto-Rayleigh-Taylor instability. Jets or spheromaks launched into a background, low-$β$ magnetized plasma show similar behavior as above, respectively, in both cases.

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Yue Zhang, Dustin M. Fisher, Mark Gilmore, Scott C. Hsu, Alan G. Lynn. 2018-03-21. Experimental investigation of coaxial-gun-formed plasmas injected into a background transverse magnetic field or plasma. https://doi.org/10.1063/1.5019727

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