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Maximum Particle Energies by Fermi Acceleration and the Origin of Cosmic Rays above the Knee

Charles D. Dermer
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Abstract

We derive the maximum accelerated particle energy from first-order and second-order Fermi acceleration at nonrelativistic and relativistic shocks for explosions taking place in a uniform surrounding medium. Second-order stochastic processes in relativistic flows are shown to be capable of accelerating cosmic rays to ultra-high energies. Cosmic rays above the knee of the cosmic ray spectrum can be accelerated by the second-order Fermi mechanism in relativistic flows, such as those occuring in gamma-ray bursts and unusual supernovae like SN 1998bw.

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Charles D. Dermer. 2001-07-11. Maximum Particle Energies by Fermi Acceleration and the Origin of Cosmic Rays above the Knee. https://arxiv.org/abs/astro-ph/0012490

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