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arXiv · 1812.09475

High-Energy Cosmic Rays from Radio Galaxies

Björn Eichmann
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Abstract

A detailed investigation of radio galaxies has recently stressed these sources as the possible origin of the cosmic rays observed above $3\,\text{EeV}$. Here, the relevance of this model at energies below $3\,\text{EeV}$ is investigated. So, it is shown that the average contribution of radio galaxies can accurately explain the observed CR flux between the second knee and the ankle in the case of a strong source evolution. However, the model cannot provide the increasing heaviness and variance at energies $\lesssim 1\,\text{EeV}$ of the observed chemical composition. In addition, it is exposed that the resulting variance of the chemical composition at Earth shows also at higher energies a clear disagreement with the observations, indicating that the compositional contributions by Centaurus A and Cygnus A need to be less different.

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Björn Eichmann. 2018-12-22. High-Energy Cosmic Rays from Radio Galaxies. https://doi.org/10.1051/epjconf/201921004001

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