The Influence of Material Composition and Geometry of Heterogeneous Medium with Resonance Scattering on the Density of Fast Neutrons Remote from the Source

An option of high-density neutron flux generation locally, at a distance from the source, is considered in this paper. The energy dependence of the cross sections of neutron scattering by nuclei of some isotopes displays resonance behavior. Below the resonance level by energy, there is a deep drop of the scattering cross section dictated by the effect of resonance and potential scattering interference. When a slowing-down neutron gets the energy corresponding to a very small scattering cross section, it is capable of flying for several meters without interaction with nuclei of the medium. The possibilities of creating conditions for selection of high-energy neutrons emitted by a reactor or other source and moving in the required direction are investigated in the paper. The research described in the paper is focused on various factors (material composition, geometry) influencing the neutron radiation density and achievable neutron flux limits.