1205.6435 (S. V. Toitsky)

A doublet of cosmic-ray events with primary energies >10^20 eV    [PDF]

S. V. Toitsky

The Telescope Array Collaboration has observed a cosmic-ray event with estimated primary energy of 1.38*10^20 eV whose arrival direction coincides (see arxiv:1205.5984), given the angular resolution of 1.5 deg, with that of an event with estimated primary energy of 1.23*10^20 eV observed by the Pierre Auger Observatory. The total number of events with energies >10^20 eV published by both experiments is six. I estimate the statistical significance of the doublet, which is rather weak, and point out that the arrival directions of events in the doublet coincide with the Galactic X-ray source Aql X-1.

View original: http://arxiv.org/abs/1205.6435