Related papers: Cosmic Rays with Energy Above 10^{17} ev
An intermediate-scale energy spectrum anisotropy has been found in the arrival directions of ultra-high energy cosmic rays of energies above $10^{19.2}$ eV in the northern hemisphere, using 7 years of data from the Telescope Array surface…
Ultra-high energy cosmic rays interacting with the radiation fields in the universe cause electromagnetic cascades resulting in a flux of extragalactic gamma rays, detectable to some 100 GeV. Recent precise measurements of the extragalactic…
Analytical calculations of extra-galactic cosmic ray spectra above ~10^17 eV are often performed assuming continuous source distributions, giving rise to spectra that depend little on the propagation mode, be it rectilinear or diffusive. We…
A model is introduced, in which the irregularity spectrum of the Galactic magnetic field beyond the dissipation length scale is first a Kolmogorov spectrum $k^{-5/3}$ at small scales $\lambda \, = \, 2 \pi/k$ with $k$ the wave-number, then…
In this paper we show that the conventional diffusive shock acceleration mechanism for cosmic rays associated with relativistic astrophysical shocks in active galactic nuclei (AGNs) has severe difficulties to explain the highest energy…
A model to describe cosmic ray spectra in the energy region from 10 GeV to 100 PeV is suggested based on the assumption that Galactic cosmic ray flux is a mixture of fluxes accelerated by shocks from nova and supernova of different types.…
Air showers recorded by the Haverah Park Array during the years 1974 - 1987 have been re-analysed. For the original estimate of the energy spectrum, a relationship between the ground parameter $\rho$(600) and the primary energy, as…
We present the results of a search for cosmic ray point sources at energies above 10^19 eV in the HiRes stereo data set. The analysis is based on a maximum likelihood ratio test using the probability density function for each event rather…
This analysis aims to determine the mass composition and energy of cosmic rays at energies above 100 TeV based on the lateral distribution of extensive air showers. Here, we propose quite a few air shower observables for reconstructing 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…
Ultrahigh energy cosmic rays are the most energetic of any subatomic particles ever observed in nature. The quest for their mysterious origin is currently a major scientific challenge. Here we explore the possibility that these particles…
Angular correlations of ultra-high energy cosmic rays with cosmologically distant sources may provide clues to these mysterious events. We compare cosmic ray tracks with energies above $ 10^{20}eV$ to a compilation of radio-loud compact QSO…
In this chapter I give an overview of shock acceleration, including a discussion of the maximum energies possible and the shape of the spectrum near cut-off, interactions of high energy cosmic rays with, and propagation through, the…
The clustering of ultrahigh energy (>10^{20} eV) cosmic rays (UHECR) suggests that they might be emitted by compact sources. Statistical analysis (Dubovsky et al., 2000) estimated the source density. We extend their analysis to give also…
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 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…
We analyze the spectrum of the ultrahigh energy (above \approx 10^{9} GeV) cosmic rays. With a maximum likelihood analysis we show that the observed spectrum is consistent with the decay of extragalactic GUT scale particles. The predicted…
Substantial amount of information both on the source and on characteristics of intercepting magnetic fields is encoded in the distribution in arrival times, directions, and energies of charged ultra-high energy cosmic rays from discrete…
Ultra High Energy Cosmic Rays, UHECR, are charged particles with energies between $\sim10^{18}\,{\rm eV}$ and $\sim3\times10^{20}\,{\rm eV}\sim50\,{\rm J}$. They exhibit fundamental physics at energies inaccessible to terrestrial…
Five ultrahigh energy cosmic rays in the combined AGASA and HiRes stereo data are analyzed to test whether they come from a single source. The quad above 37 EeV in the 94-event high energy dataset can be analyzed without considering…