Related papers: The Pierre Auger Observatory Open Data
The origin and nature of ultrahigh-energy cosmic rays (UHECRs) are one of the most intriguing mysteries in particle astrophysics and astronomy. The two largest observatories, the Pierre Auger Observatory and the Telescope Array Experiment,…
Unveiling the sources of ultra-high-energy cosmic rays remains one of the main challenges of high-energy astrophysics. Measurements of anisotropies in their arrival directions are key to identifying their sources, yet magnetic deflections…
In this paper, the connection between Pierre Auger Observatory measurements and photons is discussed. Three cases are presented: the search for photons in the ultrahigh-energy cosmic-ray radiation, the impact of the photon background in the…
We report a measurement of the flux of cosmic rays with unprecedented precision and statistics using the Pierre Auger Observatory. Based on fluorescence observations in coincidence with at least one surface detector we derive a spectrum for…
We argue that the data published by the Pierre Auger Collaboration (arXiv:0711.2256) disfavor at 99% confidence level their hypothesis that most of the highest-energy cosmic rays are protons from nearby astrophysical sources, either Active…
Studies of the correlations of ultra-high energy cosmic ray directions with extra-Galactic objects, of general anisotropy, of photons and neutrinos, and of other astrophysical effects, with the Pierre Auger Observatory. Contributions to the…
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 Pierre Auger Collaboration is exploring the potential of radio-detection techniques to measure the extensive air showers. The main advantage of these setups is the possibility to cover a large area with no atmospheric attenuation and…
An upper limit of 16% (at 95% c.l.) is derived for the photon fraction in cosmic rays with energies greater than 10^19 eV, based on observations of the depth of shower maximum performed with the hybrid detector of the Pierre Auger…
Ongoing and planned enhancements of the Pierre Auger Observatory
The mass composition of ultra-high-energy cosmic rays is an open problem in astroparticle physics. It is usually inferred from the depth of the shower maximum (Xmax) of cosmic-ray showers, which is only ambiguously determined by modern…
After a century of observations, we still do not know the origin of cosmic rays. I will review the current state of cosmic ray observations at the highest energies, and their implications for proposed acceleration models and secondary…
The Auger Engineering Radio Array (AERA) is an enhancement of the Pierre Auger Observatory in Argentina. Covering about View the $17\,$km$^2$, AERA is the world-largest antenna array for cosmic-ray observation. It consists of more than 150…
In this contribution, we present the status and first data from the Radio Detector (RD) at the Pierre Auger Observatory, consisting of $1660$ radio antennas deployed across the $3000$ km$^2$ surface detector array. These antennas measure…
We present a measurement of the cosmic-ray spectrum above 100\,PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750~m. An inflection of the spectrum is observed, confirming the presence of the…
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the…
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 fluorescence-detection techniques of cosmic-ray air-shower experiments require precise knowledge of atmospheric properties to reconstruct air-shower energies. Up to now, the atmosphere in desert-like areas was assumed to be stable…
The fluorescence detector (FD) of the Pierre Auger Observatory is currently operating 18 fluorescence telescopes of the 24 that will be employed in the completed detector. These telescopes, grouped in 4 eyes each consisting of 6 telescopes,…
The Pierre Auger Observatory (PAO) and Telescope Array (TA) collaborations report significant differences in the observed energy spectra of ultra-high-energy cosmic rays (UHECRs) above 30~EeV. In this work we present a joint fit of TA and…