A simulation model investigation of neutron-oxygen inelastic scattering and subsequent nucleus deexcitation based on experimental data

TL;DR

This paper evaluates and improves neutron-oxygen inelastic scattering models using experimental data, aiming to reduce uncertainties in neutrino detector simulations, especially for Super-Kamiokande.

Contribution

It identifies the optimal combination of simulation models (INCL++ and NucDeEx) for accurate neutron-oxygen interaction modeling based on experimental data.

Findings

INCL++ and NucDeEx combination aligns well with experimental data

Improved modeling reduces systematic uncertainties in neutrino interactions

Enhances future neutrino detector physics analyses

Abstract

The nuclear interaction model plays an essential role in understanding neutrino-nucleus interactions in large-scale neutrino detectors. For example, in the Super-Kamiokande experiment, systematic uncertainties regarding atmospheric neutrino interactions on oxygen limit the sensitivity to some physics studies, such as the diffuse supernova neutrino background search. Reduction of such uncertainties necessitates an accurate modeling of nuclear reactions and subsequent nuclear deexcitation. For this purpose, a detailed study was performed by comparing various combinations of simulation models with the newly released neutron experimental data. From this study, it is found that the combination of INCL++ and NucDeEx implemented in a Geant4-based simulation shows a better agreement with the experimental data. The presented result will be referred to improve the future physics studies at neutrino detectors, including the current focus of Super-Kamiokande.