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Diffusive Shock Acceleration in Unmodified Relativistic, Oblique Shocks

Donald C. Ellison·Glen P. Double
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Abstract

We present results from a fully relativistic Monte Carlo simulation of diffusive shock acceleration (DSA) in unmodified shocks. The computer code uses a single algorithmic sequence to smoothly span the range from nonrelativistic speeds to fully relativistic shocks of arbitrary obliquity, providing a powerful consistency check. While known results are obtained for nonrelativistic and ultra-relativistic parallel shocks, new results are presented for the less explored trans- relativistic regime and for oblique, fully relativistic shocks. We find, for a wide trans-relativistic range extending to shock Lorentz factors >30, that the particle spectrum produced by DSA varies strongly from the canonical f(p) proportional to p^{-4.23} spectrum known to result in ultra-relativistic shocks. Trans- relativistic shocks may play an important role in gamma-ray bursts and other sources and most relativistic shocks will be highly oblique.

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Donald C. Ellison, Glen P. Double. 2004-08-27. Diffusive Shock Acceleration in Unmodified Relativistic, Oblique Shocks. https://doi.org/10.1016/j.astropartphys.2004.08.005

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