Full Monte-Carlo description of the Moscow State University Extensive Air Shower experiment

TL;DR

This paper presents a comprehensive Monte-Carlo model of the EAS-MSU detector array, enabling detailed analysis of cosmic ray data and supporting the investigation of potential gamma-ray signals at PeV energies.

Contribution

It introduces a full Monte-Carlo simulation framework for the EAS-MSU experiment, improving data interpretation and detector performance understanding.

Findings

Good agreement between data and simulations

Supports analysis of muonless shower excess

Facilitates future physical results extraction

Abstract

The Moscow State University Extensive Air Shower (EAS-MSU) array studied high-energy cosmic rays with primary energies ~(1-500) PeV in the Northern hemisphere. The EAS-MSU data are being revisited following recently found indications to an excess of muonless showers, which may be interpreted as the first observation of cosmic gamma rays at ~100 PeV. In this paper, we present a complete Monte-Carlo model of the surface detector which results in a good agreement between data and simulations. The model allows us to study the performance of the detector and will be used to obtain physical results in further studies.