Study of the neutron field from a hadronic cascade in iron: Verification of a Monte Carlo calculational model by comparison with measured data

The Monte Carlo code FLUNEV, an extension of the hadronic shower code FLUKA for production and transport of neutrons below 50 MeV, is modified by reduction both of the total energy carried by intranuclear cascade particles and of the excitation energy preceding the evaporation step in inelastic hadron-nucleus collisions, following phenomenological suggestions given by Alsmiller and Alsmiller (Nucl. Instr. and Meth. A278 (1989) 713), and by Barashenkov et al. (Dubna report JINR/E2-89-437 (1989)). The modified version of our code is verified by comparison with experimental neutron distributions around thin iron targets and thick iron absorbers irradiated by high energy protons, and with earlier calculations of neutron fields. Good agreement is achieved in most cases. (orig.)