Modeling gamma ray production from proton-proton interactions in high-energy astrophysical environments

TL;DR

This paper models gamma ray production from proton-proton interactions in astrophysical environments using advanced hadronic interaction models, providing tools for researchers to interpret gamma ray data and infer proton spectra.

Contribution

It introduces a comprehensive comparison of high-energy hadronic interaction models calibrated with LHC data for gamma ray production in astrophysics.

Findings

Comparison of SIBYLL 2.1, QGSJET-II-04, and EPOS LHC models.

Provision of lookup tables for gamma ray production.

Enhanced understanding of hadronic gamma ray emission mechanisms.

Abstract

Gamma rays are the best probes to study high-energy particle interactions occurring in astrophysical environments. Space based instruments such as Fermi Large Area Telescope (Fermi LAT) and ground based experiments such as VERITAS, H.E.S.S. and MAGIC have provided us with valuable data on various production mechanisms of gamma rays within our Galaxy and beyond. Depending on astronomical conditions, gamma rays can be produced either by hadronic or leptonic interactions. In this paper, we probe the production of gamma rays by the hadronic channel where gamma rays are primarily produced by the decay of secondary neutral pions and $\eta$ mesons from proton-proton interactions in a wide energy range. We use state of the art high-energy hadronic interaction models, calibrated with the new LHC results and widely used in ground based ultra-high energy air shower experiments. We also compare SIBYLL 2.1, QGSJET-II-04 and EPOS LHC models and provide lookup tables which can be used by researchers to model gamma ray production from the hadronic channel and ultimately extract the underlying proton spectrum from gamma ray observations.