Measurement of 56Fe activity produced in inelastic scattering of neutrons created by cosmic muons in an iron shield

We report on the study of the intensities of several gamma lines emitted after the inelastic scattering of neutrons in 56Fe. Neutrons were produced via nuclear processes induced by cosmic muons in the 20 tons 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 the 252Cf neutrons. Assessment against the published data from neutron scattering experiments at energies up to 14 MeV is also provided. It allowed us to infer the qualitative information about the average energy of muon-created neutrons in the iron shield.Peer reviewed: YesNRC publication: Ye