Re-analysis of the primary mass composition in the 'knee region' on the basis of the Tien Shan data and the independent-nucleon model of A-A interactions

Abstract

Experimental results on EAS muon and electron size fluctuations obtained in the Tien Shan experiment are reanalysed using a more realistic model of nucleus-nucleus collision and taking into account the influence of the zenith angle distribution on the width of fluctuations and the difference in the shape of muon lateral distributions in EAS initiated by different primary nuclei. The corrected primary mass composition in the 'knee region' is likely to be heavier than at lower energies.