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Ultrahigh Energy Cosmic Rays: New Physics or Old Physics?

F. W. Stecker
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Abstract

We consider the advantages of and the problems associated with hypotheses to explain the origin of ulthrahigh energy cosmic rays (UHECR: E > 10 EeV) and the "trans GZK" cosmic rays (TGZK: E > 100 EeV), both through "old physics" (acceleration in cosmic sources) and "new physics" (new particles, topological defects, fat neutrino cross sections, Lorentz invariance violation).

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F. W. Stecker. 2004-07-15. Ultrahigh Energy Cosmic Rays: New Physics or Old Physics?. https://doi.org/10.1016/j.nuclphysbps.2004.10.028

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