Anisotropy studies with multiscale autocorrelation function

TL;DR

This paper introduces a new multiscale autocorrelation method to detect anisotropy in cosmic ray arrival directions, independent of source catalogs, effective even with isotropic background contamination.

Contribution

The paper proposes a novel, catalog-independent multiscale autocorrelation technique for anisotropy detection in high-energy cosmic rays.

Findings

Effective in simulated data with plausible cosmic ray scenarios

Good discrimination power against isotropic backgrounds

Applicable to data from surface detector observatories

Abstract

We present a novel method, based on a multiscale approach, for detecting anisotropy signatures in the arrival direction distribution of the highest energy cosmic rays. This method is catalog independent, i.e. it does not depend on the choice of a particular catalog of candidate sources, and it provides a good discrimination power even in presence of contaminating isotropic background. We present applications to simulated data sets of events corresponding to plausible scenarios for events detected, in the last decades, by world-wide surface detector-based observatories for charged particles.