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Particle Acceleration in Relativistic Flows

J. G. Kirk
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Abstract

A property common to several different astrophysical sources of high-energy gamma-rays is the presence of bulk motion at relativistic speed. The intrinsic spectra of the nonthermal radiating particles also show interesting similarities, with a pronounced hardening towards lower energies. This suggests two distinct acceleration mechanisms could be at work in these sources. At high energies, the stochastic first-order Fermi process at shocks seems to provide a reasonable explanation. I will briefly review the status of this mechanism before discussing the possibility that, at lower energies, non-stochastic acceleration in the induced electric field of a relativistic current sheet plays a role.

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J. G. Kirk. 2005-03-15. Particle Acceleration in Relativistic Flows. https://arxiv.org/abs/astro-ph/0503316

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