Magnetic field evolution in relativistic unmagnetized collisionless shocks

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.

ApJ Letters, published (minor corrections, results unchanged)

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Cited by in corpus (5)

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• Radiative cooling in relativistic collisionless shocks. Can simulations and experiments probe relevant GRB physics?
• Modeling Spectral Variability of Prompt GRB Emission within the Jitter Radiation Paradigm
• GRB: magnetic fields, cosmic rays, and emission from first principles?