A search was conducted for TeV -rays emitted from the direction of the ultra–high-energy cosmic ray detected by the Fly’s Eye experiment with energy E 3 1020 eV. No enhancement was found at a level of 10 10 cm 2 s 1 for E > 350 GeV. A steady source of ultra–high-energy cosmic ray protons or photons would be expected to produce a -ray flux above this level. An upper limit was also set for the fl...

Cosmic Rays (CR) travel at speeds essentially indistinguishable from the speed of light. However whilst travelling through magnetic fields, both regular and turbulent, they are delayed behind the light since they are usually charged particles and their paths are not linear. Those delays can be so long that they are an impediment to correctly identifying sources which may be variable in time. Fu...

The accurate determination of the elemental composition of cosmic rays at high energies is expected to provide crucial clues on the origin of these particles. Previous direct measurements of composition have been limited by experiment collecting power, resulting in marginal statistics above 10 eV, precisely the region where the “knee” of the cosmic-ray energy spectrum is starting to develop. In...

the dependence of the lateral distribution of cherenkov light in simulated extensive air showers to the energy and the mass of the primary cosmic rays has been studied. it has been shown that a previous claim about mass independent proportionality of shower energy to the total cherenkov photon number is not valid in energies below eeas ~ 1014 ev. we have found that the core distance of the so c...

The dependence of the lateral distribution of Cherenkov light in simulated extensive air showers to the energy and the mass of the primary cosmic rays has been studied. It has been shown that a previous claim about mass independent proportionality of shower energy to the total Cherenkov photon number is not valid in energies below EEAS ~ 1014 eV. We have found that the core distance of the so c...

A new version of the Monte Carlo event generator DPMJET for air shower simulations is presented. It is a code system based on the Dual Parton Model and combines all features of the DTUNUC-2, DPMJET-II and PHOJET 1.12 event generators. DPMJET-III allows the simulation of hadron-hadron, hadron-nucleus, nucleus-nucleus, photonhadron, photon-photon and photon-nucleus interactions from a few GeV up ...