Related papers: Ultra High Energy Cosmic Rays: Anisotropies and Sp…
The Pierre Auger Observatory is the largest astroparticle experiment in operation. Complementary to the measurements of the charged ultra-high energy (UHE) cosmic rays, it provides a very good sensitivity to the detection of UHE photons and…
An anisotropy signal for the arrival directions of ultra-high energy cosmic rays (UHECR) of more than 99% confidence level was established using data collected by the Pierre Auger Observatory. Cosmic rays with energy above $\sim 6 \times…
Current experiments collecting high statistics in ultra-high energy cosmic rays (UHECRs) are opening a new window on the universe facing the possibility to perform UHECR astronomy. Here we discuss a large scale structure (LSS) model for the…
We present a combined fit of a simple astrophysical model of UHECR sources to both the energy spectrum and mass composition data measured by the Pierre Auger Observatory. The fit has been performed for energies above 5 EeV, i.e. the region…
We have calculated the probability that the clustering of arrival directions of ultra-high energy cosmic rays (UHECRs) is consistent with a finite number of uniformly distributed proton sources. The case of a continuous source distribution…
We analyze the distribution of arrival directions of ultra-high energy cosmic rays recorded at the Pierre Auger Observatory in 10 years of operation. The data set, about three times larger than that used in earlier studies, includes arrival…
Context: As more and more data are collected by cosmic ray experiments such as the Pierre Auger Observatory and Telescope Array (TA), the search for the sources of the Ultra High Energy Cosmic Rays (UHECR) continues. Already we have some…
We obtain the dipolar anisotropies in the arrival directions of ultra-high energy cosmic rays diffusing from nearby extragalactic sources. We discuss both the energy regime of spatial diffusion and the quasi-rectilinear one leading to just…
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…
Over the last decade a number of important observational results have been reported using data from the Pierre Auger Observatory. We shall review some of the recent key findings that have significantly advanced our understanding of…
The Pierre Auger Observatory advances the study of ultra-high-energy cosmic rays through a hybrid system of surface and fluorescence detectors. This paper presents recent results, including refined spectrum measurements, anisotropy…
Here we discuss the latest developments in the debate, where the ultrahigh energy cosmic ray particles come from. In this brief review, we emphasize the predictions that necessarily follow from the various concepts proposed. We discuss both…
Recent results from the Pierre Auger Observatory show energy dependent chemical composition of ultrahigh-energy cosmic rays (UHECR) with a growing fraction of heavy elements at high energies. This points to a non-negligible contribution of…
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…
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…
One of the models recently proposed to explain the origin of the ultra high energy cosmic rays assumes that these particles may be accelerated by the electromotive force around presently inactive quasar remnants. We study predictions for…
In its Phase I, the Pierre Auger Observatory has led to several observations, driving the field of ultra-high-energy cosmic ray (UHECR) research over the last 20 years. Major achievements obtained so far include the unprecedented precise…
Recent data from the Pierre Auger Observatory has revealed the presence of a large-scale dipole in the arrival direction distribution of ultra-high energy cosmic rays (UHECR). In this work, we build up an understanding of the diffusive…
We use an updated version of {\it SimProp}, a Monte Carlo simulation scheme for the propagation of ultra-high energy cosmic rays, to compute cosmogenic neutrino fluxes expected on Earth in various scenarios. These fluxes are compared with…
The Auger experiment was designed to study the high-energy cosmic rays by measuring the properties of the showers produced in the atmosphere. The Southern Auger Observatory has taken data since January 2004. Results on mass composition,…