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arXiv · 0802.3217

Magnetic field evolution in relativistic unmagnetized collisionless shocks

Uri Keshet·Boaz Katz·Anatoly Spitkovsky·Eli Waxman
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Abstract

We study relativistic unmagnetized collisionless shocks using unprecedentedly large particle-in-cell simulations of two-dimensional pair plasma. High energy particles accelerated by the shock are found to drive magnetic field evolution on a timescale >10^4 plasma times. Progressively stronger magnetic fields are generated on larger scales in a growing region around the shock. Shock-generated magnetic fields and accelerated particles carry >1% and >10% of the downstream energy flux, respectively. Our results suggest limits on the magnetization of relativistic astrophysical flows.

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Uri Keshet, Boaz Katz, Anatoly Spitkovsky, Eli Waxman. 2009-03-09. Magnetic field evolution in relativistic unmagnetized collisionless shocks. https://doi.org/10.1088/0004-637x%2F693%2F2%2Fl127

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