12–23 Jul 2021
Online
Europe/Berlin timezone

Muon excess in ultra-high energy inclined EAS according to the NEVOD-DECOR data

14 Jul 2021, 18:00
1h 30m
03

03

Talk CRI | Cosmic Ray Indirect Discussion

Speaker

R.P. Kokoulin (MEPhI)

Description

Data of the NEVOD-DECOR experiment on investigations of inclined cosmic ray muon bundles for a long time period (May 2012 – March 2021) are presented. Their comparison with the results of calculations based on simulations of EAS hadron and muon components allows one to study the behavior of the energy spectrum and mass composition of primary cosmic rays and/or to check the validity of hadron interaction models in a wide energy range from about 10^16 to more than 10^18 eV. The analysis showed that the observed intensity of muon bundles at primary particle energies of about 10^18 eV and higher can be compatible with the expectation only under the assumption of an extremely heavy mass composition of cosmic rays. This conclusion is consistent with data of a number of other experiments investigating the muon component of air showers at ultra-high energies. On the contrary, measurements of the depth of the shower maximum in the atmosphere (Xmax) in the experiments using air fluorescence technique favor a light mass composition of primary cosmic rays at these energies. This contradiction (so-called “muon puzzle”) cannot be resolved without serious changes of the existing hadron interaction models.

Keywords

Inclined muon bundles, 10 - 1000 PeV primary energies

Subcategory Experimental Results

Primary authors

Presentation materials