Related papers: Probing hadronic interactions at the 100 TeV scale…

High-energy cosmic rays are observed indirectly by detecting the extensive air showers initiated in Earth's atmosphere. The interpretation of these observations relies on accurate models of air shower physics, which is a challenge and an…

We propose a method to extract high-energy hadronic interaction properties from the distributions of two of the main observables of proton extensive air showers: the depth of maximum shower development, $X_\mathrm{max}$, and the number of…

The Pierre Auger Observatory is the largest air-shower detector in the world, offering unparalleled exposure to photons with energies above $5 \times 10^{16}$ eV. Since the start of data collection almost two decades ago, numerous searches…

The number of muons in an air shower is a strong indicator of the mass of the primary particle and increases with a small power of the cosmic ray mass by the $\beta$-exponent, $N_{\mu} \sim A^{(1-\beta)}$. This behaviour can be explained in…

Measurements of the muon content of extensive air showers at the highest energies show discrepancies compared to simulations as large as the differences between proton and iron. This so-called muon puzzle is commonly attributed to a lack of…

Whereas air shower simulations are very valuable tools for interpreting cosmic ray data, there is a long standing problem: is seems to be impossible to accommodate at the same time the longitudinal development of air showers and the number…

The upgrade of Pierre Auger Observatory, AugerPrime, is a multi-hybrid system designed to improve the sensitivity and precision of ultra-high-energy cosmic ray measurements. It includes scintillator detectors positioned both atop the…

We report an investigation of the mass composition of cosmic rays with energies from 3 to 100 EeV (1 EeV=$10^{18}$ eV) using the distributions of the depth of shower maximum $X_\mathrm{max}$. The analysis relies on ${\sim}50,000$ events…

Several methods can be used to perform statistical inference of primary composition of cosmic rays measured with water Cerenkov detectors as those in use at the Pierre Auger Southern Observatory. In the present work we assess the impact of…

Understanding hadronic interactions at high energies represents a very important ingredient for modeling high energy cosmic ray air showers. In this paper, we present a new approach to simulate hadronic interactions, including…

Neutrons are the only neutral hadrons that remain stable over the timescale of an air-shower development. Their energy is lost only through hadronic interactions and quasi-elastic scattering, which results in their high abundance at the…

Cosmic-rays with energies up to $3\times10^{20}$ eV have been observed. The nuclear composition of these cosmic rays is unknown but if the incident nuclei are protons then the corresponding center of mass energy is $\sqrt{s_{nn}} = 700$…

The general features of the neutrino flux from cosmic ray interactions in the Earth's atmosphere are well characterized. However, the absolute precision of calculations is still insufficient and the uncertainty from the modeling of hadronic…

The analysis of high-energy air shower data allows one to study the proton-air cross section at energies beyond the reach of fixed target and collider experiments. The mean depth of the first interaction point and its fluctuations are a…

The Pierre Auger Observatory has led to significant advances in our understanding of ultra-high-energy cosmic rays. These new insights have driven a major upgrade of the Observatory, known as AugerPrime, through which the experiment has…

The evolution of the muon content of very high energy air showers (EAS) in the atmosphere is investigated with data of the KASCADE-Grande observatory. For this purpose, the muon attenuation length in the atmosphere is obtained to…

We present the design and science case for a new array of radio antennas to be located at the Pierre Auger Observatory. Six stations of three SKALA antennas each will be deployed around a single water-Cherenkov surface detector triggering…

This paper briefly summarizes the status of the cosmic ray observations by EAS (Extended Air Shower) experiments with energy below 10**16eV and the related studies of the hadronic interaction models. Based on the observed sharp knee…

Studies of the composition of the highest energy cosmic rays with the Pierre Auger Observatory, including examination of hadronic physics effects on the structure of extensive air showers.

We present measurements of the depth of shower maximum, Xmax, for cosmic-ray-induced extensive air showers recorded by the fluorescence detector of the Pierre Auger Observatory over 17 years. The data set covers primary energies from…