Related papers: Probing hadronic interactions at the 100 TeV scale…
The characteristics of extensive air showers are sensitive to the details of hadronic interactions at energies and in kinematic regions beyond those tested by human-made accelerators. Uncertainties on extrapolations of the hadronic…
The combination of fluorescence and surface detectors at the Pierre Auger Observatory offers unprecedented precision in testing models of hadronic interactions at center-of-mass energies around 70 TeV and beyond. However, for some time,…
The characteristics of an extensive air shower derive from both the mass of the primary ultra-high-energy cosmic ray that seeds its development and the properties of the hadronic interactions that feed it. With its hybrid detector design,…
The development of an extensive air shower depends not only on the nature of the primary ultra-high-energy cosmic ray but also on the properties of the hadronic interactions. For energies above those achievable in human-made accelerators,…
Extensive air showers are the result of billions of particle reactions initiated by single cosmic rays at ultra-high energy. Their characteristics are sensitive both to the mass of the primary cosmic ray and to the fine details of hadronic…
The Pierre Auger Observatory, the world's largest observatory of ultra-high-energy cosmic rays (UHECR), offers a unique insight into the properties of hadronic interactions occurring in air showers at energies well above those reached at…
The hybrid design of the Pierre Auger Observatory allows for the measurement of a number of properties of extensive air showers initiated by ultra-high energy cosmic rays. By comparing these measurements to predictions from air shower…
Extensive air showers are complex objects, resulting of billions of particle reactions initiated by single cosmic ray at ultra-high-energy. Their characteristics are sensitive both to the mass of the primary cosmic ray and to the details of…
The Pierre Auger Observatory is the world's largest detector for observation of ultra-high-energy cosmic rays (UHECRs) (above the energy of $10^{17}$ eV). It consists of a Fluorescence Detector (FD) and an array of particle detectors known…
The aim of the Pierre Auger Observatory is the investigation of the nature of cosmic ray particles at ultra-high energies. It can simultaneously observe the longitudinal air shower development in the atmosphere as well as particle densities…
The Pierre Auger Observatory is the largest facility in the world to study ultra-high-energy cosmic rays. It has a hybrid detection technique that combines the observation of the longitudinal development of extensive air showers and the…
The Pierre Auger Observatory in Argentina provides the largest data sample of the cosmic ray events with energy above 10$^{18}$ eV. These high energy events can be used to test our understanding of the hadronic interactions at energies…
The Pierre Auger Observatory allows the measurement of both longitudinal profiles and lateral particle distributions of high-energy showers. The former trace the overall shower development, mainly of the electromagnetic component close to…
The Pierre Auger Observatory is the world's largest detector of ultra--high energy cosmic rays (UHECRs). It uses an array of fluorescence telescopes and particle detectors at the ground to obtain detailed measurements of the energy…
The combined data of Fluorescence and Surface Detectors of the Pierre Auger Observatory has recently provided the strongest constraints on the validity of predictions from current models of hadronic interactions. The unmodified predictions…
The Pierre Auger Observatory is a hybrid detector for cosmic rays with E > 1EeV. From the gathered data we estimated the proton-proton cross-section at sqrt(s) = 55 TeV and tested other features of the hadronic interaction models, which use…
The Pierre Auger Observatory, recently completed, has been operational since 2004. As a hybrid experiment, it allows for a wide range of measurements of UHECR-induced extensive air showers (EAS), including measurements of the EAS particle…
The interaction of Ultra High Energy Cosmic Rays (UHECRs) with the atoms of the atmosphere can occur at center-of-mass energies that surpass 100 TeV, while present human-made accelerators go up to 13 TeV. Therefore it provides a unique…
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…
We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower…