The number of muons measured in hybrid events detected by the Pierre Auger Observatory

Collaboration
Jul 25, 2023
13 pages
Published in:
  • PoS ICRC2023 (2023) 339
Contribution to:
  • Published: Jul 25, 2023
Experiments:

Citations per year

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Abstract: (SISSA)
The number of muons produced in air showers is a reliable proxy for theamount of hadron production that occurs during the shower development. Itis, therefore, an important observable in the context of identifying the masscomposition of ultrahigh-energy cosmic rays.Beyond LHC energies, however, hadronic multiparticle production as itoccurs in air showers from ultrahigh-energy cosmic rays, is poorlyunderstood, and there is little to no way to directly test it experimentally. Insimulations, current models of hadronic interactions are unable to producethe average number of muons that is measured by multiple air-showerexperiments.In this work, we estimate the number of muons in vertical hybrid eventsdetected by both the fluorescence and surface detectors of the Pierre AugerObservatory above a primary energy of 3 EeV. To reconstruct the signal, weuse a model of the water-Cherenkov detector responses that is based on air-shower universality. We take into account the effect of the longitudinalshower development on the lateral distribution of the signal at the ground, aswell as the primary energy estimated from the calorimetric energy depositionof the air shower. In this way, we are able to precisely estimate the amount ofmuons created in vertical showers, relative to expectations from simulatedshowers using modern hadronic interaction models.
  • showers: atmosphere
  • model: hadronic
  • interaction: model
  • detector: surface
  • hadron: production
  • muon
  • air
  • hybrid
  • cosmic radiation
  • observatory