Testing hadronic interactions at ultrahigh energies with air showers measured by the Pierre Auger Observatory

THE PIERRE AUGER COLLABORATION (VER A. LUCERO EN LISTA AUTORES ARCHIVO ADJUNTO)

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Año: 2016 vol. 117 p. 1 - 9

0031-9007

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (ECM=110x170 TeV),whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33+/-0.16 (1.61+/-0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.