Developments in shower reconstruction and composition analysis for CARPET-3 EAS array

Abstract

This contribution describes the current progress on the composition analysis of data recorded with Carpet EAS detector. The focus of the paper is on the methodologi- cal side of analysis. A study of the primary composition in the PeV region can currently be carried out solely by means of extensive air shower (EAS) measurements. These measurements rely on the use of different particle interaction models describing the development of EAS in the atmosphere and indicate that the mass composition of primary spectrum change in the PeV re- gion, as reviewed and discussed by Blet al. (2009). As direct experiments measuring the primary particle spectrum at and above the PeV region are not in the foreseeable future, further ground based observations on the properties of EAS with different detection and analysis techniques are needed. Precision measurements of the lateral density functions (LDFs) of charged particles in EAS have been performed with the Carpet EAS array. This measurement can give fur- ther light on the composition of the primary cosmic-ray par- ticles in the knee region. This contribution focuses on some of the aspects relevant to the development of the new methods of analysis of the Carpet EAS data. The experimental LDFs, compared with simulated ones (CORSIKA QGSJET 01C,Heck et al., 1998), are presented and further description is given on the progress of the development of analysis methods. Such developments are needed for analysis of new data and for analysis of the newly proposed Carpet-3 EAS array.