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Constraints on Particle Acceleration from the Diffuse Isotropic Gamma-Ray Background

Karl Mannheim
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Abstract

Gamma rays trace accelerated particles, and the observed flux of extragalactic gamma rays therefore constrains the global efficiency for particle acceleration. Extragalactic jets in active galactic nuclei can account for the gamma ray background if their particle acceleration efficiency considerably exceeds ~ 18 per cent which would imply that particle acceleration is an essential part of the thermodynamics in these sources.

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Karl Mannheim. 2000-05-26. Constraints on Particle Acceleration from the Diffuse Isotropic Gamma-Ray Background. https://doi.org/10.1023/a%3A1002426929706

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