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arXiv · hep-ph/0512267

GZK photons as UHECR above 10$^{19}$ eV

Graciela B. Gelmini
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Abstract

"GZK photons" are produced by extragalactic nucleons through the resonant photoproduction of pions. We present the expected range of the GZK photon fraction of UHECR, assuming a particular UHECR spectrum and primary nucleons, and compare it with the minimal photon fraction predicted by Top-Down models.

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Graciela B. Gelmini. 2005-12-20. GZK photons as UHECR above 10$^{19}$ eV. https://doi.org/10.1088/1742-6596%2F39%2F1%2F108

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