Testing Hadronic Interactions at Ultrahigh Energies with Air Showers Measured by the Pierre Auger Observatory

THE PIERRE AUGER COLLABORATION (P HANSEN PERTENECE A LA COLABORACIÓN AUGER)

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Lugar: New York; Año: 2016 vol. 117 p. 192001 - 192008

0031-9007

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach ofaccelerators. Here we introduce a new method to test hadronic interaction models without relying on theabsolute energy calibration, and apply it to events with primary energy 6?16 EeV (ECM ¼ 110?170 TeV),whose longitudinal development and lateral distribution were simultaneously measured by the Pierre AugerObservatory. The average hadronic shower is 1.33 0.16 (1.61 0.21) times larger than predicted usingthe leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.