Correlating Fermi gamma-ray sources with ultra-high energy cosmic rays

Abstract

The origin of ultra-high energy cosmic rays (UHECRs) is one of the enduring mysteries of high-energy astrophysics. To investigate this, we cross-correlate the recently released Fermi Large Area Telescope First Source Catalog (1FGL) with the public sample of UHECRs made available by the Pierre Auger collaboration. Of the 27 UHECRs in the sample, we find 12 events that arrived within 3.1 degrees of Fermi sources. However, we find similar or larger number of matches in 63 out of 100 artificial UHECR samples constructed using positions randomly drawn from the BATSE 4B catalog of gamma-ray bursts (GRBs) collected from 1991 until 1996. Based on our analysis, we find no evidence that UHECRs are associated with Fermi sources. We conclude with some remarks about the astrophysical origin of cosmic rays.

Revised version that considers a smaller deflection angle for UHECRs (3.1 degrees) and a declination range for the artificial samples that extends to decl.= +24.8 in response to the referee comments. 4 pages, 2 figures, submitted to MNRAS

References in corpus (3)

• Ultra High Energy Cosmic Rays from Black Hole Jets of Radio Galaxies
• Search for Correlations between HiRes Stereo Events and Active Galactic Nuclei
• Ultra-High Energy Cosmic Rays, Spiral galaxies and Magnetars

Cited by in corpus (5)

• Do Ultrahigh Energy Cosmic Rays Come from Active Galactic Nuclei and Fermi $\gamma$-ray Sources?
• A correlation between the highest energy cosmic rays and nearby active galactic nuclei detected by Fermi
• Constraining Sources of Ultra High Energy Cosmic Rays Using High Energy Observations with the Fermi Satellite
• Searches for correlation between UHECR events and high-energy gamma-ray Fermi-LAT data
• Ultra high-energy cosmic rays from beyond the Greisen-Zatsepin-Kuz'min horizon