Gamma ray production in inelastic scattering of neutrons produced by cosmic muons in $^{56}$Fe

TL;DR

This study investigates gamma ray emissions resulting from neutron inelastic scattering in iron caused by cosmic muons, comparing natural cosmic-ray-induced neutrons with those from a $^{252}$Cf source, and assessing existing neutron scattering data.

Contribution

It provides new measurements of gamma line intensities from cosmic-ray-produced neutrons in iron and compares them with other neutron sources and published data.

Findings

Gamma line intensities vary with neutron source.

Cosmic muon-induced neutrons produce measurable gamma emissions.

Results align with some existing neutron scattering data.

Abstract

We report on the study of the intensities of several gamma lines emitted after the inelastic scattering of neutrons in $^{56}$Fe. Neutrons were produced by cosmic muons passing the 20t massive iron cube placed at the Earth's surface and used as a passive shield for the HPGe detector. Relative intensities of detected gamma lines are compared with the results collected in the same iron shield by the use of $^{252}$Cf neutrons. Assessment against the published data from neutron scattering experiments at energies up to 14 MeV is also provided.