The hadronic interaction model SIBYLL 2.3c and Feynman scaling

TL;DR

The paper introduces Sibyll 2.3c, an improved hadronic interaction model for cosmic ray air shower simulations, which incorporates Feynman scaling to enhance accuracy in particle production spectra based on recent experimental data.

Contribution

It presents the development and validation of Sibyll 2.3c, an updated version of the model that better matches Feynman scaling and recent experimental observations.

Findings

Predictions for depth of shower maximum are improved.

Muon number at ground level is more accurately modeled.

Energy spectrum of muons in air showers aligns better with data.

Abstract

The Monte Carlo model Sibyll has been designed for efficient simulation of hadronic multiparticle production up to the highest energies as needed for interpreting cosmic ray measurements. For more than 15 years, version 2.1 of Sibyll has been one of the standard models for air shower simulation. Motivated by data of LHC and fixed-target experiments and a better understanding of the phenomenology of hadronic interactions, we have developed an improved version of this model, version 2.3, which has been released in 2016. In this contribution we present a revised version of this model, called Sibyll 2.3c, that is further improved by adjusting particle production spectra to match the expectation of Feynman scaling in the fragmentation region. After a brief introduction to the changes implemented in Sibyll 2.3 and 2.3c with respect to Sibyll 2.1, the current predictions of the model for the depth of shower maximum, the number of muons at ground, and the energy spectrum of muons in extensive air showers are presented.