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Updated: Jun 12, 2026

Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Secondary photons and neutrinos from cosmic rays produced by distant blazars
Warren Essey1, Oleg E Kalashev, Alexander Kusenko
1Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547, USA.
Abstract:
Secondary photons and neutrinos produced in the interactions of cosmic ray protons emitted by distant active galactic nuclei (AGN) with the photon background along the line of sight can reveal a wealth of new information about the intergalactic magnetic fields, extragalactic background light, and the acceleration mechanisms of cosmic rays. The secondary photons may have already been observed by gamma-ray telescopes. We show that the secondary neutrinos improve the prospects of discovering distant blazars by IceCube, and we discuss the ramifications for the cosmic backgrounds, magnetic fields, and AGN models.
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