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arXiv · 1405.2286

Observation of ionization-mediated transition from collisionless interpenetration to collisional stagnation during merging of two supersonic plasmas

Auna L. Moser·Scott C. Hsu
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Abstract

We present space- and time-resolved experimental data of head-on-merging, supersonic plasma jets (of an argon/impurity mixture) in an initially collisionless regime for counter-streaming ions. The merging begins with collisionless interpenetration followed by a transition to collisional stagnation. The transition occurs due to an experimentally inferred rising mean-ionization level, which rapidly reduces the counter-streaming ion-ion mean free path. The measurements demonstrate a specific mechanism by which a collisionless interaction transitions to a collisional one and constrain collisionality and ionization models for plasmas with complex equation of state.

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Auna L. Moser, Scott C. Hsu. 2014-05-09. Observation of ionization-mediated transition from collisionless interpenetration to collisional stagnation during merging of two supersonic plasmas. https://arxiv.org/abs/1405.2286

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