Longitudinal shower development and its signature at observation level

Abstract

From a study of Cverenkov photon arrival times at various core distances at the observation level it has already been established that the photon front is well fitted with a spherical surface traveling at the speed of light and originating from a fixed point on the shower axis. The radius of curvature as measured at the observation level has been found to be roughly equal to the height of shower maximum from the observation level. In the present work we study the relationship between the radius of curvature of the shower fromt (R), the height of electron maximum (he), the Cverenkov photon maximum (hCv) and the average production height of Cverenkov photons (h-). Cverenkov pulse width (w) has always ben used as a parameter to study cascade development especially at tens of PeV energies. We discuss the relation between the w and he at TeV energies for gamma-ray and proton primaries.