Gamma-ray Signatures of Ultra High Energy Cosmic Ray Line-of-sight Interactions

Abstract

Ultra High Energy Cosmic Rays (UHECRs) interact en route to Earth, producing secondary gamma-rays. For the case of high cosmic ray power and weak intergalactic magnetic fields, the deflections of these UHECRs may be small leading to detectable gamma-ray fluxes that point back to their origin. We summarize current results and prospects of detecting a signature of these interactions using the current and next generation of imaging atmospheric Cherenkov telescopes.

White paper contribution for Snowmass 2013, and in particular for the Cosmic Frontier Working Group ("CF6: Cosmic Particles and Fundamental Physics" subgroup). 4 pages, 1 figure