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arXiv · 1509.04356

A lower bound on the number of cosmic ray events required to measure source catalogue correlations

Marco Dolci·Andrew Romero-Wolf·Stephanie Wissel
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Abstract

Recent analyses of cosmic ray arrival directions have resulted in evidence for a positive correlation with active galactic nuclei positions that has weak significance against an isotropic source distribution. In this paper, we explore the sample size needed to measure a highly statistically significant correlation to a parent source catalogue. We compare several scenarios for the directional scattering of ultra-high energy cosmic rays given our current knowledge of the galactic and intergalactic magnetic fields. We find significant correlations are possible for a sample of $>$1000 cosmic ray protons with energies above 60 EeV.

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Marco Dolci, Andrew Romero-Wolf, Stephanie Wissel. 2015-09-15. A lower bound on the number of cosmic ray events required to measure source catalogue correlations. https://doi.org/10.1088/1475-7516%2F2016%2F10%2F028

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