Related papers: The mass of cosmic rays above 1017 eV
The mass composition of high energy cosmic rays above $10^{17}$ eV is a crucial issue to solve some open questions in astrophysics such as the acceleration and propagation mechanisms. Unfortunately, the standard procedures to identify the…
We present new data on Cherenkov light observations obtained during the period 1994-2009, after a modernization of the Yakutsk EAS array. A complex analysis of $\xmax$ and its fluctuations $\sigma(\xmax)$ was performed over a wide energy…
A re-examination of the atmospheric cascade profile of the highest energy cosmic ray is presented. The study includes air-shower simulations considering different cross sections, particle multiplicity and variation of the…
A spectrum of cosmic rays within energy range 10^15 - 3x10^17 eV was derived from the data of the small Cherenkov setup, which is a part of the Yakutsk complex EAS array. In this, work a new series of observation is covered. These…
The origin and chemical composition of ultra high energy cosmic rays is still an open question in astroparticle physics. The observed large-scale isotropy and also direct composition measurements can be interpreted as an extragalactic…
Our Galaxy is the largest nuclear interaction experiment which we know, because of the interaction between cosmic ray particles and the interstellar material. Cosmic rays are particles, which have been accelerated in the Galaxy or in…
We calculate energy spectra and mass composition of cosmic rays accelerated by the galactic population of pulsars during their radio and gamma-ray phase. Several models proposed for the distribution of the initial parameters of the galactic…
Observation of Ultra High Energy Cosmic Rays (UHECR) -whose energy exceeds $10^20$eV- is still a puzzle for modern astrophysics. The transfer of more than 16 Joules to a microscopic particle can hardly be achieved, even in the most powerful…
Cosmic rays with energies above $10^{18}$ eV are currently of considerable interest in astrophysics and are to be further studied in a number of projects which are either currently under construction or the subject of well-developed…
The production of energetic particles in the universe remains one of the great mysteries of modern science. The mechanisms of acceleration in astrophysical sources and the details about the propagation through the galactic and extragalactic…
A complete model for the origin of high-energy >~10^{14} eV) cosmic rays from gamma-ray bursts (GRBs) and implications of this hypothesis are described. Detection of high-energy neutrinos from GRBs provide an unambiguous test of the model.…
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…
It is commonly accepted that high energy cosmic rays up to $10^{19}$ eV can be produced in catastrophic astrophysical processes. However the source of a few observed events with higher energies remains mysterious. We propose that they may…
Understanding the acceleration of Ultra High Energy Cosmic Rays is one of the great challenges of contemporary astrophysics. In this short review, we summarize the general observational constraints on their composition, spectrum and…
It has been argued that the observations of cosmic particles with energies in excess of $10^8$ TeV represent a puzzle. Its solution requires new astrophysics or new particle physics. We show that the latter is unlikely given that the scale…
The propagation of cosmic iron nuclei with energies above 10^19 eV from their sources to the Galaxy is discussed by assuming that cosmic rays at ultra-high energies are of extragalactic origin. In extragalactic space, cosmic nuclei interact…
We review the hypothesis that the acceleration of protons at internal shocks in Gamma Ray Bursts (GRB) could be the origin of the ultra-high energy cosmic rays (UHECR) observed at earth, E_max > 10^19 eV. We find that, even though protons…
We demonstrate by numerical flux calculations that neutrino beams producing the observed highest energy cosmic rays by weak interactions with the relic neutrino background require a non-uniform distribution of sources. Such sources have to…
It is proposed that the highest energy $\sim 10^{20}$eV cosmic ray primaries are protons, decay products of a long-lived progenitor whose high kinetic energy arises from decay of a distant (cosmological) superheavy particle, G. Such a…
Reasons for the current interest in cosmic rays above 10^19 eV are described. The latest results on the energy spectrum, arrival direction distribution and mass composition of cosmic rays are reviewed, including data that were reported…