Identifying Nearby UHECR Accelerators using UHE (and VHE) Photons

Abstract

Ultra-high energy photons (UHE, E > 10^19 eV) are inevitably produced during the propagation of 10^20 eV protons in extragalactic space. Their short interaction lengths (<20 Mpc) at these energies, combined with the impressive sensitivity of the Pierre Auger Observatory detector to these particles, makes them an ideal probe of nearby ultra-high-energy cosmic ray (UHECR) sources. We here discuss the particular case of photons from a single nearby (within 30 Mpc) source in light of the possibility that such an object might be responsible for several of the UHECR events published by the Auger collaboration. We demonstrate that the photon signal accompanying a cluster of a few > 6x10^19 eV UHECRs from such a source should be detectable by Auger in the near future. The detection of these photons would also be a signature of a light composition of the UHECRs from the nearby source.

4 pages, 2 figures, accepted for publication in PRL

References in corpus (13)

• Correlation of the highest energy cosmic rays with nearby extragalactic objects
• First Observation of the Greisen-Zatsepin-Kuzmin Suppression
• Observation of the suppression of the flux of cosmic rays above 4x10^19eV
• Constrained Simulations of the Magnetic Field in the Local Universe and the Propagation of UHECRs
• Transport of Cosmic Rays in Chaotic Magnetic Fields
• Discovery of very high energy gamma-ray emission from Centaurus A with H.E.S.S
• Upper limit on the cosmic-ray photon flux above 10^19 eV using the surface detector of the Pierre Auger Observatory
• The distance to the giant elliptical galaxy NGC 5128
• Chandra and XMM-Newton Observations of the Nucleus of Centaurus A
• GZK Photons as Ultra High Energy Cosmic Rays
• Point-like gamma ray sources as signatures of distant accelerators of ultra high energy cosmic rays
• On the Possible Association of Ultra High Energy Cosmic Rays with Nearby Active Galaxies
• The Spectral Shape and Photon Fraction as Signatures of the GZK-Cutoff

Cited by in corpus (11)

• The Astrophysics of Ultrahigh Energy Cosmic Rays
• Extragalactic propagation of ultrahigh energy cosmic-rays
• The Astrophysical Multimessenger Observatory Network (AMON): Performance and Science Program
• UHECR Composition Models
• Cosmogenic photons as a test of ultra-high energy cosmic ray composition
• Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons
• Detectability of ultrahigh energy cosmic ray signatures in gamma rays
• Selected Topics in Cosmic Ray Physics
• Tracing Cosmic accelerators with Decaying Neutrons
• Simulation study of GZK photon fluxes
• Gamma Ray Burst as Sources of Exotic Particles