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arXiv · 1707.03309

Collisionless shocks in laboratory astrophysics experiments

Shikha Bhadoria·Naveen Kumar·Christoph H. Keitel
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Abstract

Influence of the plasma collisions on the laser-driven collisionless shock formation and subsequent ion acceleration is studied on the basis of two different collisional algorithms and their implementations in two well-known particle-in-cell codes EPOCH and SMILEI. In this setup, an ultra-intense incident laser pulse generates hot-electrons in a thick target, launching an electrostatic shock at the laser-plasma interface while also pushing the interface through the hole-boring effect. We observe, to varying degrees, the weakening of the space-charge effects due to collisions and improvements ($\ge 10\%$) in the energy spectra of quasi-monoenergetic ions in both PIC codes EPOCH and SMILEI. These results establish the `collisionlessness' of the collisionless shocks in laboratory astrophysics experiments.

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Shikha Bhadoria, Naveen Kumar, Christoph H. Keitel. 2017-07-11. Collisionless shocks in laboratory astrophysics experiments. https://arxiv.org/abs/1707.03309

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