Ultra-high-energy cosmic rays (UHECRs) hit the Earth's atmosphere with energies
exceeding 1018 eV. This is the same energy as carried by a tennis ball moving at 100 km h …

To take up the challenge of understanding the origin of the ultra-high-energy cosmic rays
(UHECRs), new observational means appear necessary. The JEM-EUSO Collaboration has …

The nature of ultra-high energy cosmic rays (UHECRs) above 1017 eV is still unknown,
even if data collected in the last decade have partially answered these puzzling questions …

We calculate the number density and luminosity of the sources of ultra-high energy cosmic
rays (UHECRs), using the information about the small scale anisotropies and the observed …

Recent evidence from the Pierre Auger Observatory suggests a transition, at 5 EeV-10EeV
in the composition of Ultra High Energy Cosmic Rays (UHECRs), from protons to heavier …

We introduce the new version of SimProp, a Monte Carlo code for simulating the
propagation of ultra-high energy cosmic rays in intergalactic space. This version, SimProp …

Since their first observation in 1962, the existence of Ultra High Energy Cosmic Rays
(UHECR) remains a mystery in modern astrophysics. Those cosmic rays, with energies well …

We discuss the possibility of accurately estimating the source number density of ultra-high-
energy cosmic rays (UHECRs) using small-scale anisotropy in their arrival distribution. The …

Modern observatories of ultra-high energy cosmic rays (UHECR) have collected over 104
events with energies above 10 EeV, whose arrival directions appear to be nearly …

The search for ultra-high energy (UHE) photons is a key to reveal the origin of the highest
energetic cosmic rays. Nuclei interacting with the extra-galactic background light, dominantly …