Related papers: Depth of Maximum of Air-Shower Profiles at the Pie…
We fit the recently published Pierre Auger ultra-high energy cosmic ray spectrum assuming that either nucleons or nuclei are emitted at the sources. We consider the simplified cases of pure proton, or pure oxygen, or pure iron injection. We…
The predictions of hadronic interaction models for cosmic-ray induced air showers contain inherent uncertainties due to limitations of available accelerator data and theoretical understanding in the required energy and rapidity regime.…
Based on solutions of the cascade equations, the air-shower universality is a framework that for all air showers with the same energy, zenith angle, depth of shower maximum, and muon number predicts the same longitudinal, lateral, and…
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…
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…
At Auger energies only model predictions enable us to extract primary cosmic ray features. The simulation of the shower evolution depends sensitively on the first few interactions, necessarily related to the quality of our understanding of…
Measurements of the Elongation Rate of the depth of shower maximum above 1 EeV are reviewed. There is evidence, from four independent estimates of this rate, made in the two hemispheres using three different techniques, for a decrease in…
Telescope Array (TA) has completed analysis of nearly nine years of data measuring the atmospheric depth of air shower maximum ($X_{\textrm{max}}$) utilizing the TA surface detector array and the Black Rock Mesa and Long Ridge fluorescence…
Astroparticles offer a new path for research in the field of particle physics, allowing investigations at energies above those accesible with accelerators. Ultra-high energy cosmic rays can be studied via the observation of the showers they…
We discuss the electromagnetic collisions of high energy protons, pions and kaons with atmospheric nuclei. In particular, we use the equivalent photon approximation to estimate (i) the diffractive collisions where the projectile scatters…
The dependence of atmospheric conditions on altitude and time have to be known at the site of an air shower experiment for accurate reconstruction of extensive air showers and their simulations. The height-profile of atmospheric depth is of…
The determination of the mass composition of the highest energy cosmic rays is one of the greatest challenges in cosmic ray experiments. The highest energy cosmic rays are only detected indirectly because of their very low flux. Using the…
The understanding of the basic properties of the ultra - high energy extensive air showers is strongly dependent on the description of the hadronic interactions in a energy range beyond that probed by the LHC. One of the uncertainties…
Using CORSIKA simulations, we investigate the mass sensitivity of cosmic-ray air-shower observables for sites at the South Pole and Malarg\"ue, Argentina, the respective locations of the IceCube Neutrino Observatory and the Pierre Auger…
The Pierre Auger Observatory (PAO) has measured the spectrum and composition of the ultrahigh energy cosmic rays with unprecedented precision. We use these measurements to constrain their spectrum and composition as injected from their…
The muon content of extensive air showers is an observable sensitive to the primary composition and to the hadronic interaction properties. The Pierre Auger Observatory uses water-Cherenkov detectors to measure particle densities at the…
A key step towards the understanding of the origin of ultra-high energy cosmic rays is their mass composition. Primary photons and neutrinos produce markedly different showers from nuclei, while showers of different nuclear species are not…
We fit the cosmic-ray spectrum measured with the Pierre Auger Observatory's surface detectors above an energy of $10^{17}$ eV, along with composition information inferred from the depth of shower maximum measured with its fluorescence…
The atmospheric depth where the energy deposit profile of secondary particles from extensive air showers (EAS) reaches its maximum, $X_{\rm max}$, is related to the primary particle mass. The mass composition of the ultra-high energy cosmic…
Large scale airshower simulations around the GZK cutoff are performed. An extensive analysis of the behaviour of the various subcomponents of the cascade is presented. We focus our investigation both on the study of total and partial…