Measurements of the Muon Content of UHECR Air Showers with the Pierre Auger Observatory

TL;DR

This paper reports on measurements of muon content in ultra-high-energy cosmic ray air showers using the Pierre Auger Observatory, providing insights into high-energy hadronic interactions and cosmic ray composition.

Contribution

It presents new independent measurements of muon content at 10 EeV, informing models of particle interactions and cosmic ray origins.

Findings

Muon measurements suggest discrepancies with existing hadronic interaction models.

Results imply a mixed composition of cosmic rays at ultra-high energies.

Data constrains models of particle interactions at energies beyond current accelerators.

Abstract

The Pierre Auger Observatory, recently completed, has been operational since 2004. As a hybrid experiment, it allows for a wide range of measurements of UHECR-induced extensive air showers (EAS), including measurements of the EAS particle content on ground which is sensitive to high-energy hadronic interactions. We present the results of several independent measurements of the EAS muon content on ground in Auger data at a primary energy of 10 EeV. We discuss implications on high-energy hadronic interaction models and cosmic ray composition.