Multiscale autocorrelation function: a new approach to anisotropy studies

TL;DR

This paper introduces a new multiscale autocorrelation method for detecting anisotropy in ultra-high-energy cosmic ray arrival directions, effective for various data sizes and backgrounds.

Contribution

It presents a novel, catalog-independent, scale-dependent approach that improves anisotropy detection in cosmic ray data over existing methods.

Findings

Effective discrimination in both large and small datasets.

Robust against strong isotropic backgrounds.

Validated with simulated cosmic ray data.

Abstract

We present a novel catalog-independent method, based on a scale dependent approach, to detect anisotropy signatures in the arrival direction distribution of the ultra highest energy cosmic rays (UHECR). The method provides a good discrimination power for both large and small data sets, even in presence of strong contaminating isotropic background. We present some applications to simulated data sets of events corresponding to plausible scenarios for charged particles detected by world-wide surface detector-based observatories, in the last decades.