Related papers: Experimental Summary: Very High Energy Cosmic Rays…
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…
We review the experimental evidences about flux and mass composition of ultra high energy cosmic rays in connection with theoretical scenarios concerning astrophysical sources. In this context, we also address the discussion about the…
A brief motivation for studying cosmic rays at energies 10^14 < E < 10^17 eV is given. Besides astrophysical interests in identifying and understanding their sources, there are also particle physics aspects related to their transport…
We explore scenarios where the highest energy cosmic rays (HECR) are produced by new particle physics near the grand unification scale. Using detailed numerical simulations of extragalactic cosmic and gamma-ray propagation, we show the…
The present white paper is submitted as part of the "Snowmass" process to help inform the long-term plans of the United States Department of Energy and the National Science Foundation for high-energy physics. It summarizes the science…
We will discuss the main relevant aspects of the physics of ultra high energy cosmic rays. After a short recap of the experimental evidences, we will review theoretical models aiming at describing the sources of these extremely energetic…
Some new developments obtained in the last few years concerning the propagation of high energy cosmic rays are discussed. In particular, it is shown how the inclusion of drift effects in the transport diffusion equations leads naturally to…
Over the last 30 years or so, a handful of events observed in ground-based cosmic ray detectors seem to have opened a new window in the field of high-energy astrophysics. These events have energies exceeding 5x10**19 eV (the region of the…
Experimental results from Haverah Park, Yakutsk, AGASA and Fly's Eye are reviewed. All these experiments work in the energy range above 0.1 EeV. The 'dip' structure around 3 EeV in the energy spectrum is well established by all the…
Recent observations on ultra high energy cosmic rays (those cosmic rays with energies greater than $\sim 4 \times 10^{18}$ eV) suggest an abundant flux of incoming particles with energies above $1 \times 10^{20}$ eV. These observations…
The workshop on "Hadron-Hadron and Cosmic-Ray Interactions at multi-TeV Energies" held at the ECT* centre (Trento) in Nov.-Dec. 2010 gathered together both theorists and experimentalists to discuss issues of the physics of high-energy…
Scattering processes in the cosmic microwave background limit the propagation of ultra high energy charged particles in our Universe. For extragalactic proton sources resonant photopion production results in the famous…
The paper describes methods used for the detection of cosmic rays with energies above 10^18 eV (UHECR, UltraHigh Energy Cosmic Rays). It had been anticipated there would be a cutoff in the energy spectrum of primary cosmic rays around 3…
The shape of the longitudinal development of the showers generated in the atmosphere by very high energy cosmic ray particles encodes information about the mass composition of the flux, and about the properties of hadronic interactions that…
Most QCD models of high energy collisions predict that the inelasticity $K$ is an increasing function of the energy. We argue that, due to percolation of strings, this behaviour will change and, at $\sqrt{s} \simeq 10^4$ GeV, the…
In this contribution we summarize the highlights from the Pierre Auger Observatory presented at the 35th International Cosmic Ray Conference. We discuss the update of the measurement of the energy spectrum of cosmic rays over a wide range…
An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to be gradually dominated by an extra-galactic component. In…
We will review the main physical aspects of Ultra High Energy Cosmic Rays. We will discuss in particular their propagation through astrophysical backgrounds, focusing on the latest experimental observations of HiRes, Telescope Array and…
The highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic processes in the Universe. Their existence triggered a flurry of theoretical explanations ranging from…
Recent measurements of ultra-high energy cosmic rays and neutrinos are briefly reviewed. With several new large scale observatories nearing completion or becoming fully operational only very recently, a large body of high quality and high…