Extragalactic cosmic rays

M. Kachelriess

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arXiv · 2201.04535

Extragalactic cosmic rays

M. Kachelriess

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Abstract

I review the status of ultrahigh-energy cosmic ray (UHECR) physics.After introducing the main experimental results and summarizing possible intepretations, I discuss observational and theoretical constraints on the sources of UHECRs. I comment also briefly on the role of magnetic fields. Combining these constraints, I argue that luminuous and numerous AGN types as FR-I and Seyfert galaxies, or alternatively hypernovae, are the most promising UHECR sources. Finally, I sketch few of the models presented at the conference before concluding.

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M. Kachelriess. 2022-01-12. Extragalactic cosmic rays. https://arxiv.org/abs/2201.04535

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