Related papers: Composition Studies with the Pierre Auger Observat…
The Pierre Auger Observatory, a hybrid detector for the study of ultra-high energy cosmic rays (UHECRs), is now approaching completion. After describing Auger present status and performance, with an emphasis on the advantages provided by…
In this paper some recent results from the Pierre Auger Collaboration are presented. These are the measurement of the energy spectrum of cosmic rays over a wide range of energies ($10^{17.5}$ to above $10^{20}$ eV), studies of the…
The Pierre Auger Observatory detects ultra-high energy cosmic rays by implementing two complementary air-shower techniques. The combination of a large ground array and fluorescence detectors, known as the "hybrid" concept, means that a rich…
At the southern site of the Pierre Auger Observatory, which is close to completion, an exposure that significantly exceeds the largest forerunner experiments has already been accumulated. We report a measurement of the cosmic ray energy…
We present measurements of the atmospheric depth of the shower maximum $X_\mathrm{max}$, inferred for the first time on an event-by-event level using the Surface Detector of the Pierre Auger Observatory. Using deep learning, we were able to…
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 fluorescence technique has been successfully used to detect ultrahigh energy cosmic rays by indirect measurements. The underlying idea is that the number of charged particles in the atmospheric shower, i.e, its longitudinal profile, can…
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…
The Pierre Auger Observatory is the largest extensive air shower detector. Based on a hybrid system, this experiment measures the longitudinal shower development and the particles at the ground. This detection system allows the extraction…
The Pierre Auger Observatory has been taking data on the highest energy cosmic rays for the equivalent of over a year of full detector aperture. Comments are presented on results published so far.
High-energy cosmic rays impinging onto the atmosphere of the Earth initiate extensive air showers. With the LOFAR radio telescope and the Auger Engineering Radio Array (AERA) at the Pierre Auger Observatory radio emission from air showers…
The Pierre Auger Observatory can detect with high efficiency the air showers induced by ultra-high energy cosmic rays incident at large (> 60 deg.) zenith angles. We describe here the specific characteristics of inclined and horizontal…
The Pierre Auger Cosmic-Ray Observatory uses the earth's atmosphere as a calorimeter to measure extensive air-showers created by particles of astrophysical origin. Some of these particles carry joules of energy. At these extreme energies,…
The Pierre Auger Observatory's (PAO) shower profile measurements can be used to constrain the chemical composition of the ultra-high energy cosmic ray (UHECR) spectrum. In particular, the PAO's measurements of the average depth of shower…
The determination of the primary energy of extensive air showers using the fluorescence detection technique requires an estimation of the energy carried away by particles that do not deposit all their energy in the atmosphere. This…
Measurements of air showers are accumulating at an increasing rate while construction proceeds at the Pierre Auger Observatory. Although the southern site is only half complete, the cumulative exposure is already similar to those achieved…
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 in Malargue, Argentina, is designed to study the origin of ultrahigh energy cosmic rays with energies above 10^18 eV. The energy calibration of the detector is based on a system of four air fluorescence…
We show that the maximum shower depth distributions of Ultra-High Energy Cosmic Rays (UHECRs), as measured by fluorescence telescopes, can be augmented by building a mapping to observables collected by surface detectors. The resulting…
The Pierre Auger Observatory has been detecting ultra-high energy cosmic rays (UHECRs) for more than fifteen years. An essential feature of the Observatory is its hybrid design: cosmic rays above $100~$PeV are detected through the…