Alborz observatory is an EAS array in the heights of Alborez mountain chain near Tehran. For the development of the array, more number of detectors is inevitable. The managing the financial resources and achieving the highest efficiency of the array is important for the project. Therefore, Water Cherenkov Detectors has been used for 9 months in the same way as the previous experiment with Scint...

Simulations of optical image of a shower are implemented into a procedure of shower energy determination. This ”top-down” approach starts with shower development and fluorescence light production in the air, to obtain the expected detector response. In this paper, distributions of energy deposited by a shower in the air through ionization, as obtained from CORSIKA, are used to derive the flux o...

In extensive air showers induced by ultra-high-energy (UHE) cosmic rays, secondary photons are expected to be produced at energies far above those accessible other means. It has been shown that the decay of such photons, as possible in certain theories allowing Lorentz violation, can lead significant changes shower development. Based on observations average depth maximum $\left<X_\text{max}\rig...

The IceCube neutrino detector is built into the Antarctic ice sheet at the South Pole to measure high energy neutrinos. For this, 4800 photomultiplier tubes (PMTs) are being deployed at depths between 1450 and 2450 meters into the ice to measure neutrino induced charged particles like muons. IceTop is a surface air shower detector consisting of 160 Cherenkov ice tanks located on top of IceCube....

The KASKADE and CORSIKA air shower generators are compared to the data collected by MASS2 balloon experiment in 1991. The test of longitudinal profile for proton, helium and muon flux production provide good constraints on these air shower generators. KASKADE and CORSIKA especially with the new simulator UrQMD for low energies are found to fit these data well. This study is limited to a compari...

The HIJING and VENUS models of relativistic hadron-nucleus and nucleus-nucleus collisions are used to study interactions of proton and nuclei with nitrogen , specific for the extensive air shower developments initiated by cosmic rays in the atmosphere. The transverse energy,transverse momenta and secondary particles produced spectra as well as their energy and mass dependence were investigated ...

Calorimetric measurements of extensive air showers are performed with the fluorescence detector of the Pierre Auger Observatory. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory operates several instruments to record atmospheric conditions across and above the detector site. New developments have been made in the study of the aerosol optical ...

Model calculations are performed of extensive air shower (EAS) component energies using a variety of hadronic interaction parameters. A conversion factor from electromagnetic component energy to the energy of ultra-high energy cosmic rays (UHECRs) and its model and primary mass dependence is studied. It is shown that model dependence of the factor minimizes under the necessary condition of the ...

The problem of the uniqueness of solutions during the evaluation of primary energy spectra in the knee region using an extensive air shower (EAS) data set and the EAS inverse approach is investigated. It is shown that the unfolding of primary energy spectra in the knee region leads to mutually compensative pseudo solutions. These solutions may be the reason for the observed disagreements in the...