The effect of advected magnetic fields in jet propagation experiments

Pulsed power-driven ablation of conical wire arrays has been used to produce supersonic, radiatively cooled jets which are scalable to astrophysical systems [1]. In these experiments, the advected magnetic field can become dynamically significant, especially in the jet-ambient interaction. To enable the full range of jet-ambient interactions to be studied, it is desirable to be able to modify jet magnetisation within the same experimental setup.

We present experimental results from a new conical wire array jet-launching platform, in which the magnetic field advected by the jet is significantly reduced in comparison with previous experiments. This is achieved by preconditioning the wires with a current pre-pulse, allowing the formation of a supersonic jet driven by a fast plasma implosion. These experiments are carried out on the MAGPIE pulsed power generator (∼1 MA, 250 ns), using a suite of spatially and temporally resolved diagnostics, including laser interferometry, Faraday rotation polarimetry and high speed self-emission imaging.

[1] D. Ampleford et al. PRL 2008