The chemical composition of primary cosmic rays in the energy range ~10**15 eV from muon energy spectrum with the Okayama muon telescope

H. MATSUMOTO, A. IYONO, M. MASUDA, T. WADA, I. YAMAMOTO, S. TSUJI, K. OKEI, T. NAKATSUKA, Y. YAMASHITA  AND N. OCHI.

30th International Cosmic Ray Conference

Merida, Mexico