Detection of Local Sources of Thermal Neutrons Using Devices with a Plate Neutron Collimator

This study investigates the characteristics of a parallel plate collimator (Soller collimator) for neutrons, based on metal plates coated with a mixture of polyethylene and boron carbide, both with natural isotope composition and enriched with boron-10. Monte-Carlo simulations of the response function for various Soller collimator designs for thermal neutrons are presented, considering the neutron beam's energy spectrum, and collimation angle. The dependence of the collimator's angular resolution on the plate height, the distance between plates, the thickness of the polyethylene and boron carbide coating, and the number of plates has been studied. It is demonstrated that two point sources of thermal neutrons, located at an angular distance of approximately 6-7 degrees, can be identified as separate sources (resolved in space) using a detector with the studied collimator through space scanning.