Selection and reconstruction of very inclined air showers with the Surface Detector of the Pierre Auger Observatory

TL;DR

This paper discusses methods for selecting and reconstructing very inclined air showers detected by the Pierre Auger Observatory's surface detectors, focusing on muon-rich signals and geomagnetic effects to improve understanding of such events.

Contribution

It introduces specialized algorithms for the selection and reconstruction of inclined air showers using muon maps derived from simulations, enhancing analysis capabilities.

Findings

Effective algorithms for inclined shower reconstruction

Accurate acceptance calculations for inclined events

Improved understanding of muonic component in air showers

Abstract

The water-Cherenkov tanks of the Pierre Auger Observatory can detect particles at all zenith angles and are therefore well-suited for the study of inclined and horizontal air showers (60 - 90 degrees). Such showers are characterised by a dominance of the muonic component at ground, and by a very elongated and asymmetrical footprint which can even exhibit a lobular structure due to the bending action of the geomagnetic field. Dedicated algorithms for the selection and reconstruction of such events, as well as the corresponding acceptance calculation, have been set up on basis of muon maps obtained from shower simulations.