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The aim of this study is to reproduce a superalfvenic collisionless shock wave by using the Plasma Focus Facility as a plasma source. The experiments were performed on PF-3 Facility (Plasma Focus Filippov-type) at the level of energy supply up to 1 MJ. At compression of a current-plasma sheet to an axis in the stage of a plasma focus formation, the generation of cumulative plasma jets driven along the axis with a velocity ∼ 10 7 cm/s takes place. This directed driving is realized in the ambient plasma arisen as a result of the working gas ionization by the X-ray radiation of the plasma focus. The transversal magnetic field up to 2500 G was created by the magnetic system based on rare-earth magnets. The experimental conditions allowed us to perform experiments with Alfvén Mach number MA≥3.

High Mach number shocks have been studied experimentally at the Kurchatov Institute in 2000 with the PF3 Plasma Focus [N. V. Filippov et al., Phys. Lett. A 211, 168 (1996)]. The main goal of these especially designed laboratory experiments was to provide data against which to test current numerical models, in order to better understand the interaction of a high-velocity plasma jet with a partially ionized gas in a strong transversal magnetic field. Observed magnetic field compression, plasma density profile evolution, and shock slowing down, are well reproduced by a two-dimensional hybrid code HAWAI2D [B. Lembege and F. Simonet, Phys. Plasmas 8, 3967 (2001)] with Monte Carlo collisions. Some of the code initial conditions are directly obtained from the numerous diagnostics installed in the experimental chamber. Others are derived from jet velocity and background density measurements, making use of a simplified model of jet propagation from the pinch. Ion-neutral collisions play a central role in the shock dynamics, as demonstrated in the simulations.

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