Magnetic field evolution in relativistic unmagnetized collisionless shocks

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.

Note:

ApJ Letters, published (minor corrections, results unchanged)

References(3)

Figures(3)

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Vorticity and Magnetic Field Generation from Initial Anisotropy in Ultrarelativistic Gamma-Ray Burst Blastwaves

e-Print:
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