Related papers: The mass of cosmic rays above 1017 eV
We give a summary of the theoretical attempts to make sense of the observational data concerning the highest energy cosmic rays, (E > 3x10^{19} eV).
We report a calculation of the expected rate of inclined air showers induced by ultra high energy cosmic rays to be obtained by the Auger Southern Observatory assuming different mass compositions. We describe some features that can be used…
We present arguments aiming at reconciling apparently contradictory results concerning the chemical composition of cosmic rays of highest energy, coming recently from the Auger and HiRes collaborations. In particular, we argue that the…
We assume an extreme scenario, in which the arriving cosmic rays are composed of only iron nuclei at energies above $10^{19.6}\,\text{eV}\simeq40\,\text{EeV}$, while allowing a freedom in the scale of the depth of shower maximum…
Although cosmic rays were discovered a century ago, we do not know where or how they are accelerated. There is a realistic hope that the oldest problem in astronomy will be solved soon by ambitious experimentation: air shower arrays of…
Air showers, produced by the interaction of energetic cosmic rays with the atmosphere, are an excellent alternative to study particle physics at energies beyond any human-made particle accelerator. For that, it is necessary to identify…
A very recent observation by the Auger Observatory group claims strong evidence for cosmic rays above 56 EeV being protons from Active Galactic Nuclei. If, as would be expected, the particles above the ankle at about 2 EeV are almost all of…
The lateral distribution of muons with ~1.0x\sec(\theta) GeV in extensive air showers within ~10^{17}-10^{19} eV energy region obtained during different observational periods from November 1987 to June 2013 has been analyzed. Experimental…
We explore the feasibility of estimating primary cosmic ray composition at ultra high energies from the sum of muon, electron and photon densities and the depth of maximum of extensive air showers detected by the Auger Observatory. From the…
This is the first of a series of papers analysing the Galactic Cosmic Ray composition and origin. We show that the Galactic Cosmic Ray source (GCRS) composition is best described in terms of (i) a general enhancement of the refractory…
The cosmic ray primary composition in the energy range between 10**15 and 10**16 eV, i.e., around the "knee" of the primary spectrum, has been studied through the combined measurements of the EAS-TOP air shower array (2005 m a.s.l., 10**5…
Ground based observations appear to indicate that Ultra High Energy Cosmic Rays (UHECR) of the highest energies (>10^{18.7} eV) consist of heavy particles -- shower depth and muon production data both pointing towards this conclusion. On…
We study the dependence of extensive air shower development on the first hadronic interactions at ultra-high energies occurring in the startup phase of the air shower cascade. The interpretation of standard air shower observables depends on…
Cosmic rays with energies exceeding $10^{17}$ eV are frequently registered by measurements of the fluorescence light emitted by extensive air showers. The main uncertainty for the absolute energy scale of the measured air showers is coming…
Primary cosmic ray particles above energies of about 100 TeV are investigated by large-area ground based detector installations, observing various components of the development of extensive air-showers (EAS). By such an indirect access to…
Considerations of the collision losses for protons traversing the 2.7 K black body microwave radiation field have led to the conclusion that the highest energy cosmic rays, those observed at $\geq 10^{20}$ eV, must come from sources within…
We present arguments aiming to reconcile the apparently contradictory results concerning the chemical composition of cosmic rays of highest energy, coming recently from Auger and HiRes collaborations. In particular, we argue that the energy…
This review summarizes recent developments in the understanding of high-energy cosmic rays. It focuses on galactic and presumably extragalactic particles in the energy range from the knee (10^15 eV) up to the highest energies observed…
We describe a method to analyse inclined air showers produced by ultra high energy cosmic rays using an analytical description of the muon densities. We report the results obtained using data from inclined events…
We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs,…