Related papers: The AUGER experiment - status and results
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…
I review here some of the physics we are learning and expect to learn in the near future through the observation of cosmic rays. The study of cosmic rays involves a combination of data from accelerators, ground arrays, atmospheric…
The precise determination of the arrival direction of cosmic rays is a fundamental prerequisite for the search for sources or the study of their anisotropies on the sky. One of the most important aspects to achieve an optimal measurement of…
The Pierre Auger Observatory, located in La Pampa Amarilla, Argentina, has been continuously acquiring data since 2004. It comprises a surface detector array covering 3,000 km$^2$ and 27 fluorescence telescopes, designed to detect extensive…
Many models for ultra-high energy cosmic rays postulate exotic scenarios to explain the sources or the nature of these particles. A characteristic feature of these models is the prediction of a significant flux of photons at ultra-high…
The development of an extensive air shower depends not only on the nature of the primary ultra-high-energy cosmic ray but also on the properties of the hadronic interactions. For energies above those achievable in human-made accelerators,…
The impact of the solar activity on the heliosphere has a strong influence on the modulation of the flux of low energy galactic cosmic rays arriving at Earth. Different instruments, such as neutron monitors or muon detectors, have been…
We developed a new method in order to detect and quantify a potential anisotropy in the ultrahigh energy cosmic ray flux. The proposed method is a new statistical tool based upon the percolation process that is used in physics to describe…
While the Pierre Auger Observatory is a very successful instrument for ultra-high energy cosmic ray (UHECR) detection, it is increasingly used as part of various types of multi-messenger searches, in which it contributes with searches for…
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…
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…
Ultra-high energy cosmic rays impinging onto the atmosphere induce huge cascades of secondary particles. The measurement of the energy radiated by these air showers in form of radio waves enables an accurate measurement of the cosmic-ray…
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…
One of the most fascinating puzzles in particle astrophysics today is that of the origin and nature of the highest energy cosmic rays. The Pierre Auger Observatory (PAO), currently under construction in Province of Mendoza, Argentina, and…
The arrival directions of cosmic rays detected by the Pierre Auger Observatory (Auger) with energies above 39~EeV were recently reported to correlate with the positions of 23 nearby starburst galaxies (SBGs): in their best-fit model, 9.7\%…
The southern Pierre Auger Observatory is presently under construction in Malargue, Mendoza, Argentina. It combines two complementary air shower observation techniques; the detection of particles at ground and the observation of associated…
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…
Initial results of a project to detect the radio-frequency pulse associated with extensive air showers of cosmic rays are described briefly. This work is being performed at the CASA/MIA array in Utah, with the intention of designing…
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…
Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it…