Behaviour of the lateral shower age of cosmic ray extensive air showers

TL;DR

This paper presents an analytical and simulation-based study of the lateral shower age in cosmic ray air showers, exploring its behavior and correlations across different primary particles, with implications for understanding shower composition.

Contribution

It introduces a new analytical parametrization for lateral shower age and validates it using Monte Carlo simulations, enhancing understanding of shower development.

Findings

Analytical model agrees with CORSIKA simulations

Lateral shower age correlates across different primary particles

Superposition of electromagnetic sub-showers explains observed features

Abstract

Some simple arguments are introduced for a possible explanation of the behavior of the lateral shower age of proton-initiated showers. The corresponding analytical treatment based on the proposed argument is then illustrated. Using the Monte Carlo simulation (MC) code CORSIKA, we have validated how the different characteristics associated with the lateral shower age predicted in the present analytical parametrization, can be understood. The lateral shower age of a proton-initiated shower and its correlations with the lateral shower ages of electron- and neutral pion-initiated showers supports the idea that the result of superposition of several electromagnetic sub-showers initiated by neutral pions might produce the lateral density distribution of electrons of a proton initiated shower. It is also noticed with the simulated data that the stated feature still persists even in the local shower age representation.