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arXiv · hep-ph/0105348

Ultrahigh energy cosmic rays as a Grand Unification signal

Z. Fodor·S. D. Katz
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Abstract

We analyze the spectrum of the ultrahigh energy (above \approx 10^{9} GeV) cosmic rays. With a maximum likelihood analysis we show that the observed spectrum is consistent with the decay of extragalactic GUT scale particles. The predicted mass for these superheavy particles is m_X=10^b GeV, where b=14.6_{-1.7}^{+1.6}.

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Z. Fodor, S. D. Katz. 2001-05-31. Ultrahigh energy cosmic rays as a Grand Unification signal. https://arxiv.org/abs/hep-ph/0105348

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