Is the Ultra-High Energy Cosmic-Ray Excess Observed by the Telescope Array Correlated with IceCube Neutrinos?

TL;DR

This paper investigates the potential correlation between a cosmic-ray excess observed by the Telescope Array and neutrinos detected by IceCube, suggesting a possible common astrophysical source.

Contribution

It presents evidence of a spatial and spectral correlation between TA cosmic-ray excess and IceCube neutrinos, proposing a unified source explanation.

Findings

Significant spatial overlap between TA excess and IceCube neutrinos.

Consistency in spectrum and intensity indicating a common source.

Discussion of candidate astrophysical sources for both phenomena.

Abstract

The Telescope Array (TA) has observed a statistically significant excess in cosmic-rays with energies above 57 EeV in a region of approximately 1150 square degrees centered on coordinates (R.A. = 146.7, Dec. = 43.2). We note that the location of this excess correlates with two of the 28 extraterrestrial neutrinos recently observed by IceCube. The overlap between the two IceCube neutrinos and the TA excess is statistically significant at the 2$\sigma$ level. Furthermore, the spectrum and intensity of the IceCube neutrinos is consistent with a single source which would also produce the TA excess. Finally, we discuss possible source classes with the correct characteristics to explain the cosmic-ray and neutrino fluxes with a single source.