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arXiv · 1304.6524

Time-resolved characterization of the formation of a collisionless shock

H Ahmed·ME Dieckmann·L Romagnani·D Doria·G Sarri·M Cherchez·E Ianni·I Kourakis·AL Giesecke·M Notley·R Prasad·K Quinn·O Willi·M Borghesi
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Abstract

We report on the temporally and spatially resolved detection of the precursory stages that lead to the formation of an unmagnetized, supercritical collision-less shock in a laser-driven laboratory experiment. The measured evolution of the electrostatic potential associated with the shock unveils the transition from a current free double layer into a symmetric shock structure, stabilized by ion reflection at the shock front. Supported by a matching Particle-In-Cell simulation and theoretical considerations, we suggest that this process is analogeous to ion reflection at supercritical collisionless shocks in supernova remnants.

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H Ahmed, ME Dieckmann, L Romagnani, D Doria, G Sarri, M Cherchez, E Ianni, I Kourakis, AL Giesecke, M Notley, R Prasad, K Quinn, O Willi, M Borghesi. 2013-04-24. Time-resolved characterization of the formation of a collisionless shock. https://doi.org/10.1103/physrevlett.110.205001

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