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 ...

The light signal measured by fluorescence telescopes receives strongly depending on the shower geometry with respect to the detector a non-negligible contribution from additionally produced Cherenkov light. This Cherenkov contribution has to be accounted for to determine primary parameters properly. In comparison to the previous ansatz used by other experiments, the impact of a new analytical d...

Experimental observations of extensive air showers have revealed an excess the muon content with respect to their theoretical simulations, which we refer as puzzle. This puzzle hampers a precise determination ultra-high-energy cosmic ray mass composition. We investigate potential producing states dense quark-gluon matter (which call fireballs) resolve quantified data from Pierre Auger Observato...