Estimate of the Cosmic Ray Composition by a Pattern Analysis of the Core of PeV EAS

A system of large-area position sensitive multiwire proportional chambers (MWPC), installed below the hadron calorimeter of the KASCADE (KArlsruhe Shower Core and Array DEtector) central detector is able to observe the density distributions of the high energy muons and hadrons penetrating the calorimeter. By use of a classification in terms of multifractal moments, a mass sensitive parametrisation of the density distributions is given. In combination with additional measured parameters, i.e. number of reconstructed muons in the core and the shower size an artificial neural net analysis leads to an estimation of the relative abundances of the different primary components in cosmic rays in the energy region around the "knee".