A study of the primary cosmic ray composition in the energy range 5ṡ1014-5ṡ1015 eV is performed through the analysis of the deep underground muons and of the e.m. component of Extensive Air Showers detected in coincidence by the MACRO and EAS-TOP experiments at the Gran Sasso Laboratory. We conclude that: a) pure proton and Iron primary beams are excluded by the experimental data; b) a fraction of nuclei heavier than Helium is necessary to explain the experimental data both below and above the knee; c) a mixed composition, obtained a priori from extrapolations of the spectra directly measured below 100 TeV, yields a reasonable account of the observations up to the knee of the primary spectrum. © 1994.
Study of the primary cosmic ray composition around the knee of the energy spectrum
Giacomelli G.;Margiotta-Neri A.;Patrizii L.;Spurio M.;
1994
Abstract
A study of the primary cosmic ray composition in the energy range 5ṡ1014-5ṡ1015 eV is performed through the analysis of the deep underground muons and of the e.m. component of Extensive Air Showers detected in coincidence by the MACRO and EAS-TOP experiments at the Gran Sasso Laboratory. We conclude that: a) pure proton and Iron primary beams are excluded by the experimental data; b) a fraction of nuclei heavier than Helium is necessary to explain the experimental data both below and above the knee; c) a mixed composition, obtained a priori from extrapolations of the spectra directly measured below 100 TeV, yields a reasonable account of the observations up to the knee of the primary spectrum. © 1994.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.