Update on the intermediate arrival-direction analyses of the Pierre Auger Observatory

TL;DR

This paper updates the analysis of ultra-high-energy cosmic ray arrival directions using Pierre Auger Observatory data, exploring anisotropies, magnetic effects, and introducing new estimators for event rigidity to improve directional studies.

Contribution

It provides the latest results on cosmic ray anisotropy and introduces novel estimators based on detector response and neural networks for better rigidity ordering.

Findings

Distribution of cosmic rays along the supergalactic plane above 20 EeV.

Updated search for magnetic signatures in arrival directions.

Potential of new estimators to enhance small to intermediate scale analyses.

Abstract

We present an update on the arrival-direction analyses conducted on intermediate angular scales using the complete Phase I data of the Pierre Auger Observatory up to the end of $2022$ with a total exposure of $135{,}000\,\text{km}^2\,\text{sr}\,\text{yr}$. We show the arrival-direction distribution of the ultra-high-energy cosmic rays along the supergalactic plane above $20\,\text{EeV}$, and an update in the search for magnetically-induced signatures in the arrival directions. Furthermore, we present the potential of introducing estimators for the rigidity ordering of the events to enhance arrival-direction analyses on small to intermediate angular scales. To achieve this, we take advantage of two estimators working on the response of the surface detector: an analytical fit based on air-shower universality and a deep neural network.