Related papers: Ultra High Energy Cosmic Rays Diffusion in an Expa…
We discuss the region of transition between galactic and extragalactic cosmic rays. The exact shapes and compositions of these two components contains information about important parameters of powerful astrophysical sources and the…
More than 100 years after the discovery of cosmic rays and various experimental efforts, the origin of ultra-high energy cosmic rays (E > 100 PeV) remains unclear. The understanding of production and propagation effects of these highest…
We consider the problem of the cosmic ray spectrum formation assuming that cosmic rays are produced by Galactic sources. The anomalous diffusion equation proposed in our recent papers is used to describe cosmic ray propagation in the…
We discuss the production of ultra high energy neutrinos coming from the propagation of ultra high energy cosmic rays and in the framework of top-down models for the production of these extremely energetic particles. We show the importance…
One of the most striking astrophysical phenomena today is the existence of cosmic ray particles with energies in excess of 10^20 eV. While their presence has been confirmed by a number of experiments, it is not clear where and how these…
Cosmic ray nuclei fluxes are expected to be measured with high precision in the near future. For instance, high quality data on the antiproton component could give important clues about the nature of the astronomical dark matter. A very…
We model the transport of cosmic ray nuclei in the Galaxy by means of a new numerical code. Differently from previous numerical models we account for a generic spatial distribution of the diffusion coefficient. We found that in the case of…
The production of ultra high-energy cosmic rays in de Sitter invariant vacuum states is considered. Assuming the present-day universe is asymptoting toward a future de Sitter phase, we argue the observed flux of cosmic rays places a bound…
We explore scenarios where the highest energy cosmic rays are produced by new particle physics near the grand unification scale. Using detailed numerical simulations of extragalactic nucleon, gamma-ray, and neutrino propagation, we show the…
The differential energy spectrum of cosmic rays from Cherenkov radiation measurements in EAS in the energy range of 10^15-10^20eV has been compared with an anomalous diffusion model for the particles in interstellar space having fractal…
We present an introductory lecture on general features of cosmic rays, for non-experts, and some recent developments concerning cascade equations for air shower developments.
This is a written version of a series of lectures aimed at graduate students in astrophysics/particle theory/particle experiment. In the first part, we explain the important progress made in recent years towards understanding the…
We present the main results on the energy spectrum and composition of the highest energy cosmic rays of energy exceeding 10$^{18}$ eV obtained by the High Resolution Fly's Eye and the Southern Auger Observatory. The current results are…
One of the models recently proposed to explain the origin of the ultra high energy cosmic rays assumes that these particles may be accelerated by the electromotive force around presently inactive quasar remnants. We study predictions for…
We obtain the dipolar anisotropies in the arrival directions of ultra-high energy cosmic rays diffusing from nearby extragalactic sources. We discuss both the energy regime of spatial diffusion and the quasi-rectilinear one leading to just…
Although cosmic rays were discovered 90 years ago, we do not know how and where they are accelerated. There is compelling evidence that the highest energy cosmic rays are extra-galactic -- they cannot be contained by our galaxy's magnetic…
We briefly describe the energy loss processes of ultrahigh energy protons, heavier nuclei and gamma rays in interactions with the universal photon fields of the Universe. We then discuss the modification of the accelerated cosmic ray energy…
The paper starts by giving a motivation for this research and justifying the considered stochastic diffusion models for cosmic microwave background radiation studies. Then it derives the exact solution in terms of a series expansion to a…
We apply statistical inference on the Pierre Auger Open Data to discern for the first time the full mass composition of cosmic rays at different energies. Working with longitudinal electromagnetic profiles of cosmic ray showers, in…
A new Monte Carlo simulation code for the propagation of Ultra High Energy Cosmic Rays is presented. The results of this simulation scheme are tested by comparison with results of another Monte Carlo computation as well as with the results…