Search for correlations between the arrival directions of IceCube neutrino events and ultrahigh-energy cosmic rays detected by the Pierre Auger Observatory and the Telescope Array

THE PIERRE AUGER, ICECUBE AND TELESCOPE ARRAY COLLABORATION, INCLUYE S. MOLLERACH

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2016 vol. 01

1475-7516

This paper presents the results of different searches for correlationsbetween very high-energy neutrino candidates detected by IceCube and thehighest-energy cosmic rays measured by the Pierre Auger Observatory andthe Telescope Array. We first consider samples of cascade neutrinoevents and of high-energy neutrino-induced muon tracks, which providedevidence for a neutrino flux of astrophysical origin, and study theircross-correlation with the ultrahigh-energy cosmic ray (UHECR) samplesas a function of angular separation. We also study their possibledirectional correlations using a likelihood method stacking the neutrinoarrival directions and adopting different assumptions on the size of theUHECR magnetic deflections. Finally, we perform another likelihoodanalysis stacking the UHECR directions and using a sample ofthrough-going muon tracks optimized for neutrino point-source searcheswith sub-degree angular resolution. No indications of correlations atdiscovery level are obtained for any of the searches performed. Thesmallest of the p-values comes from the search for correlation betweenUHECRs with IceCube high-energy cascades, a result that should continueto be monitored.