The <lnA> study in the primary energy range 10^{16} - 10^{17} eV with the Muon Tracking Detector in the KASCADE-Grande experiment

TL;DR

This study uses the KASCADE-Grande Muon Tracking Detector to analyze muon pseudorapidity distributions in extensive air showers, testing hadronic interaction models and estimating the primary cosmic ray mass in the 10^{16} to 10^{17} eV energy range.

Contribution

It introduces a method to compare muon pseudorapidity distributions with simulations to evaluate hadronic interaction models and estimate cosmic ray composition.

Findings

Comparison of eta distributions from data and models QGSJet-II-2 and QGSJet-II-4.

Estimation of the mean logarithmic mass <lnA> of cosmic rays.

Validation of muon pseudorapidity as a probe for primary particle mass.

Abstract

The KASCADE-Grande Muon Tracking Detector enables with high accuracy the measurement of directions of EAS muons with energy above 0.8 GeV and up to 700 m distance from the shower centre. Reconstructed muon tracks are used to investigate muon pseudorapidity (eta) distributions. These distributions are nearly identical to the pseudorapidity distributions of their parent mesons produced in hadronic interactions. Comparison of the eta distributions from measured and simulated showers can be used to test the quality of the high energy hadronic interaction models. In this context a comparison of the QGSJet-II-2 and QGSJet-II-4 model will be shown. The pseudorapidity distributions reflect the longitudinal development of EAS and, as such, are sensitive to the mass of the cosmic rays primary particles. With various parameters of the eta distribution, obtained from the MTD data, it is possible to calculate the mean logarithmic mass of CRs. The results of the <lnA> analysis in the primary energy range 10^{16} eV - 10^{17} eV with the 1st quartile (Q1) of eta distribution will be presented.