Related papers: The angular resolution of the Pierre Auger Observa…
The Pierre Auger Observatory is designed to elucidate the origin and nature of Ultra High Energy Cosmic Rays using a hybrid detection technique. A first run of data taking with a prototype version of both detectors (the so called…
The surface detector of the Pierre Auger Observatory has recently been upgraded with the addition of radio antennas, forming the radio detector (RD). This contribution outlines the standard methods for reconstructing extensive air showers…
The Pierre Auger Observatory has the capability of detecting neutrino-induced extensive air showers by searching for very inclined showers with a significant electromagnetic component. In order to study the detector response of the surface…
The Auger Surface Detector consists of a large array of water Cherenkov detector tanks each with a volume of 12,000 liters, for the detection of high energy cosmic rays. The accuracy in the measurement of the integrated signal amplitude of…
We report a measurement of the cosmic ray energy spectrum obtained using the inclined events detected with the Pierre Auger Observatory. Showers with zenith angles between 60 and 80 degrees recorded in the period between 1 January 2004 and…
Fluorescence detectors of the Pierre Auger Observatory have been operating in a stable manner since January 2004. After a brief review of the physical characteristics of the detectors, the associated atmospheric monitoring, the calibration…
The rate of events measured with the surface detector of the Pierre Auger Observatory is found to be modulated by the weather conditions. This effect is due to the increasing amount of matter traversed by the shower as the ground pressure…
The goal of the Pierre Auger Observatory is to determine the still unknown nature and origin of ultra-high energy cosmic rays. The study of these elusive particles probes astrophysical sites of particle acceleration as well as fundamental…
The detectors of the surface array of the Pierre Auger Observatory are water Cherenkov tanks. The signals from each tank are read out using three photomultipliers. The energy of the primary particle is inferred from signal densities and…
The surface detector array of the Pierre Auger Observatory consists of 1600 water-Cherenkov detectors, for the study of extensive air showers (EAS) generated by ultra-high-energy cosmic rays. We describe the trigger hierarchy, from the…
The Southern part of the Pierre Auger Observatory is nearing completion, and has been in stable operation since January 2004 while it has grown in size. The large sample of data collected so far has led to a significant improvement in the…
The Pierre Auger Observatory is designed to study cosmic rays with energies greater than 10^{19} eV. Two sites are envisaged for the observatory, one in each hemisphere, for complete sky coverage. The southern site of the Auger Observatory,…
The Pierre Auger Observatory aims to determine the nature and origin of the ultra-high energy cosmic rays (UHECR). The Auger hybrid detector combines fluorescence observations of extended air showers, initiated in the atmosphere by these…
The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 10^17 eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by…
We present the spectrum of cosmic rays with energies above 2.5 EeV measured at the Pierre Auger Observatory after 19 years of operation, covering the period before the AugerPrime upgrade. Two independent event sets from the surface array of…
The energy spectrum of ultra-high energy cosmic rays above 10$^{18}$ eV is measured using the hybrid events collected by the Pierre Auger Observatory between November 2005 and September 2010. The large exposure of the Observatory allows the…
Ultra-high-energy cosmic rays (UHECR), of energy >10 EeV, arrive at the Earth regularly, but their sources, acceleration mechanisms, details of propagation through the universe, and particle composition remain mysteries. In addition, their…
The southern site of the Pierre Auger Observatory is under the construction near Malargue in Argentina and now more than 60% of the detectors are completed. The observatory has been collecting data for over 1 year and the cumulative…
Presently large systematic uncertainties remain in the description of hadronic interactions at ultra-high energies and a fully consistent description of air-shower experimental data is yet to be reached. The amount of data collected by the…
More than two years of fluorescence detector data collected in coincidence with at least one station of the surface detector array (``hybrid data'') are used to measure the flux and energy spectrum of cosmic rays above about 10$^{18}$ eV.…