Composition determination of cosmic rays from the muon content of the showers

Abstract

The origin and nature of ultra high energy cosmic rays remains being a mystery. However, great progress has been made in recent years due to the observations performed by the Pierre Auger Observatory and Telescope Array. In particular, it is believed that the composition information of the cosmic rays as a function of the energy can play a fundamental role for the understanding of their origin. The best indicators for primary mass composition are the muon content of extensive air shower and the atmospheric depth of the shower maximum. In this work we consider a maximum likelihood method to perform mass composition analyses based on the number of muons measured by underground muon detectors. The analyses are based on numerical simulations of the showers. The effects introduced by the detectors and the methods used to reconstruct the experimental data are also taken into account through a dedicated simulation that uses as input the information of the simulated showers. In order to illustrate the use of the method, we consider AMIGA (Auger Muons and Infill for the Ground Array), the low energy extension of the Pierre Auger Observatory that directly measures the muonic content of extensive air showers. We also study in detail the impact of the use of different high energy hadronic interaction models in the composition analyses performed. It is found that differences of a few percent between the predicted number of muons have a significant impact on composition determination.

arXiv comment10 pages, 8 figures

References in corpus (35)

• EPOS LHC : test of collective hadronization with LHC data
• The Pierre Auger Cosmic Ray Observatory
• KASCADE measurements of energy spectra for elemental groups of cosmic rays: Results and open problems
• Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV
• Measurements of the Cosmic Ray Composition with Air Shower Experiments
• Depth of Maximum of Air-Shower Profiles at the Pierre Auger Observatory: Measurements at Energies above 10^17.8 eV
• Black Hole Production by Cosmic Rays
• Muons in air showers at the Pierre Auger Observatory: Mean number in highly inclined events
• Testing Hadronic Interactions at Ultrahigh Energies with Air Showers Measured by the Pierre Auger Observatory
• Kneelike structure in the spectrum of the heavy component of cosmic rays observed with KASCADE-Grande
• New facts about muon production in Extended Air Shower simulations
• Hadronic Multiparticle Production at Ultra-High Energies and Extensive Air Showers
• Report on Tests and Measurements of Hadronic Interaction Properties with Air Showers
• Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum
• An upper limit to the photon fraction in cosmic rays above 10^19 eV from the Pierre Auger Observatory
• Search for ultra-high energy photons using air showers
• Energy Spectra of Elemental Groups of Cosmic Rays: Update on the KASCADE Unfolding Analysis
• Interpretation of the Depths of Maximum of Extensive Air Showers Measured by the Pierre Auger Observatory
• The primary cosmic ray composition between 10**15 and 10**16 eV from Extensive Air Showers electromagnetic and TeV muon data
• The Optimum Distance at which to Determine the Size of a Giant Air Shower
• Probing the evolution of the EAS muon content in the atmosphere with KASCADE-Grande
• Underground Muon Counters as a Tool for Composition Analyses
• A new physical phenomenon in ultra-high energy collisions
• Model Dependence of Lateral Distribution Functions of High Energy Cosmic Ray Air Showers
• Remnant Break-up and Muon Production in Cosmic Ray Air Showers
• A new method for reconstructing the muon lateral distribution with an array of segmented counters
• Sensitivity of the correlation between the depth of shower maximum and the muon shower size to the cosmic ray composition
• Influence of Low Energy Hadronic Interactions on Air-shower Simulations
• Sensitivity of EAS measurements to the energy spectrum of muons
• Reconstruction of air shower muon densities using segmented counters with time resolution
• Ultra-High Energy Cosmic Rays: Results and Prospects
• On the possibility of primary identification of individual cosmic ray showers
• Extracting a less model dependent cosmic ray composition from $X_{\max }$ distributions
• Interpretation of measurements of the number of muons in extensive air shower experiments
• A composition dependent energy scale and the determination of the cosmic ray primary mass in the ankle region

Cited by in corpus (1)

• A new basic air shower observable sensitive to the cosmic-ray elemental mass