Enhancing the cosmic-ray mass sensitivity of air-shower arrays by combining radio and muon detectors

Abstract

The muonic and electromagnetic components of air showers are sensitive to the mass of the primary cosmic particle. The sizes of the components can be measured with particle detectors on ground, and the electromagnetic component in addition indirectly via its radio emission in the atmosphere. The electromagnetic particles do not reach the ground for very inclined showers. On the contrary, the atmosphere is transparent for the radio emission and its footprint on ground increases with the zenith angle. Therefore, the radio technique offers a reliable detection over the full range of zenith angles, and in particular for inclined showers. In this work, the mass sensitivity of a combination of the radio emission with the muons is investigated in a case study for the site of the Pierre Auger Observatory using CORSIKA Monte Carlo simulations of showers in the EeV energy range. It is shown, that the radio-muon combination features superior mass separation power in particular for inclined showers, when compared to established mass observables such as a combination of muons and electrons or the shower maximum Xmax. Accurate measurements of the energy-dependent mass composition of ultra-high energy cosmic rays are essential to understand their still unknown origin. Thus, the combination of muon and radio detectors can enhance the scientific performance of future air-shower arrays and offers a promising upgrade option for existing arrays.

References in corpus (5)

• Observation of a Large-scale Anisotropy in the Arrival Directions of Cosmic Rays above $8\times 10^{18}$ eV
• Testing Hadronic Interactions at Ultrahigh Energies with Air Showers Measured by the Pierre Auger Observatory
• Radio detection of Cosmic-Ray Air Showers and High-Energy Neutrinos
• A method for high precision reconstruction of air shower Xmax using two-dimensional radio intensity profiles
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Cited by in corpus (9)

• Ultra-High-Energy Cosmic Rays: The Intersection of the Cosmic and Energy Frontiers
• Final results of the LOPES radio interferometer for cosmic-ray air showers
• Refractive displacement of the radio-emission footprint of inclined air showers simulated with CoREAS
• Framework and Tools for the Simulation and Analysis of the Radio Emission from Air Showers at IceCube
• Expected performance of air-shower measurements with the radio-interferometric technique
• Radio wavefront of very inclined extensive air-showers: a simulation study for extended and sparse radio arrays
• Studying the mass sensitivity of air-shower observables using simulated cosmic rays
• Radio Detection of ultra-high-energy Cosmic-Ray Air Showers
• Measuring the muon content of inclined air showers using AERA and the water-Cherenkov detectors of the Pierre Auger Observatory