We review open questions and prospects for progress in ultrahigh-energy cosmic ray
(UHECR) research, based on a series of discussions that took place during the “The High …

In this report we review the important progress made in recent years towards understanding
the experimental data on ultra-high-energy (E≳ 1 0 9 GeV) cosmic rays. We begin with a …

A new analysis of the data set from the Pierre Auger Observatory provides evidence for
anisotropy in the arrival directions of ultra-high-energy cosmic rays on an intermediate …

We demonstrate that a population of active galactic nuclei (AGN) can describe the observed
spectrum of ultra-high-energy cosmic rays (UHECRs) at and above the ankle, and that the …

Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival
directions of the cosmic rays with the highest-energies, which are correlated with the …

A method is developed to search for air showers initiated by photons using data recorded by
the surface detector of the Auger Observatory. The approach is based on observables …

We report the discovery of faint very high energy (VHE; E> 100 GeV) γ-ray emission from the
radio galaxy Centaurus A in observations performed with the High Energy Stereoscopic …

We review some of the recent progress in our knowledge about high-energy cosmic rays,
with an emphasis on the interpretation of the different observational results. We discuss the …

In the first part of this review we discuss the basic observational features at the end of the
cosmic ray (CR) energy spectrum. We also present there the main characteristics of each of …

This paper proposes and discusses a test of the chemical composition of ultra-high energy
cosmic rays that relies on the anisotropy patterns measured as a function of energy. In …