Related papers: Anisotropy Studies with the Pierre Auger Observato…
Models which associate the origin of the ultra-high energy cosmic rays (UHECR) with decays of relic superheavy particles predict the anisotropy of UHECR flux toward the Galactic center. We use the existing SUGAR data, which covered the…
Several explanations for the existence of Ultra High Energy Cosmic Rays invoke the idea that they originate from the decay of massive particles created in the reheating following inflation. It has been suggested that the decay products can…
We calculate the arrival direction distribution of ultra-high-energy cosmic rays (UHECRs) with a new suite of models of the Galactic magnetic field (GMF), assuming sources follow the large-scale structure of the Universe. Compared to…
Recent analyses from the Pierre Auger Collaboration suggest correlations between the arrival directions of Ultra-High-Energy Cosmic Rays (UHECRs) and catalogs of starburst galaxies (SGBs) and jetted active galactic nuclei (AGNs). We revisit…
We study anisotropy of cosmic rays in the energy range 0.2-1.4 EeV at intermediate angular scales using the public data set of the Pierre Auger Observatory. At certain scales, the analysis reveals a number of deviations from the isotropic…
Ultra High Energy Cosmic Rays are the most energetic particles directly measured, reaching orders of magnitude above those attained in the LHC. The Pierre Auger Observatory is shedding light onto the long-standing mysteries of their nature…
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…
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…
The flux of Ultra High Energy Cosmic Rays (UHECRs) at $E>10^{18.5}$ eV is believed to arise in plasma shock environments in extragalactic sources. In this paper, we present a systematic study of particle acceleration by relativistic shocks,…
We investigate the production of ultra-high-energy cosmic ray (UHECR) in relativistic jets from low-luminosity active galactic nuclei (LLAGN). We start by proposing a model for the UHECR contribution from the black holes (BHs) in LLAGN,…
Recently the Telescope Array collaboration reported an observation of cosmic ray event with very high energy 244 EeV ($2.44 \times 10^{20}$ eV). Importantly, the event is hard to correlate with the matter distribution in the local Universe,…
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…
For several decades, the origin of ultra-high-energy cosmic rays (UHECRs) has been an unsolved question of high-energy astrophysics. One approach for solving this puzzle is to correlate UHECRs with high-energy neutrinos, since neutrinos are…
We constrain the energy at which the transition from Galactic to extragalactic cosmic rays occurs by computing the anisotropy at Earth of cosmic rays emitted by Galactic sources. Since the diffusion approximation starts to loose its…
The Pierre Auger Southern Observatory in Argentina has begun taking data as it is being developed up to a final enclosed area of 3000 square kilometres. A key aspect of the project is to provide information on the origin of the highest…
We study the cosmic ray arrival distribution expected from a source of neutrons in the galactic center at energies around 1 EeV and compare it with the anisotropy detected by AGASA and SUGAR. Besides the point-like signal in the source…
We investigated the possibility of acceleration of ultra-high-energy cosmic rays (UHECRs) in nearby active galactic nuclei (AGNs) using archival multi-wavelength observational data, and then we constrained their physical conditions, i.e.,…
We investigate correlation between the arrival directions of ultra-high-energy cosmic rays (UHECRs) and the large-scale structure (LSS) of the Universe by using statistical quantities which can find the angular scale of the correlation. The…
Motivated by the detection of a significant dipole structure in the arrival directions of ultrahigh-energy cosmic rays above 8 EeV reported by the Pierre Auger Observatory (Auger), we search for a large-scale anisotropy using data collected…
Ultra-high energy photons (UHE, E > 10^19 eV) are inevitably produced during the propagation of 10^20 eV protons in extragalactic space. Their short interaction lengths (<20 Mpc) at these energies, combined with the impressive sensitivity…