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Evidence for a connection between the gamma-ray and the highest energy cosmic-ray emissions by BL Lacertae objects

D. Gorbunov·P. Tinyakov·I. Tkachev·S. Troitsky
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Abstract

A set of potentially gamma-ray--loud BL Lac objects is selected by intersecting the EGRET and BL Lac catalogs. Of the resulting 14 objects, eight are found to correlate with arrival directions of ultra--high-energy cosmic rays (UHECRs), with significance of the order of 5 sigma. This suggests that gamma-ray emission can be used as a distinctive feature of those BL Lac objects that are capable of producing UHECR.

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D. Gorbunov, P. Tinyakov, I. Tkachev, S. Troitsky. 2002-10-08. Evidence for a connection between the gamma-ray and the highest energy cosmic-ray emissions by BL Lacertae objects. https://doi.org/10.1086/344332

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