Air shower universality from 10^14 to 10^22 eV
  Scaling properties of nuclei- and photon-initiated air showers are examined in wide primary energy range ($10^{14}\div 10^{22}$~eV) taking into account Landau-Pomeranchuk-Migdal and geomagnetic field effects. It is shown that the invariance in lateral distribution and also the universal dependence between shower age and root mean square radius of electron component exist up to the highest energies. The implications of shower universality for reanalysis, cross-checking and validation of the results of different experiments together with decreasing of the influence of hadronic model uncertainties are discussed in detail. 
A A Lagutin, R I Raikin, T L Serebryakova
astro-ph.HE