Development of Collimated Fast Neutron Detection without Physical Collimator

We proposed a method for collimated detection of fast neutron without any physical collimator. In elastic scattering of fast neutron by a hydrogen atom in a detector, scattering angle can be estimated by simple kinematics with a measured direction and an energy of a recoiled proton and a pre-estimated energy of the incident fast neutron. The direction of incident fast neutron can be identified by overlap of the cones with the estimated scattering angle projected on reconstruction plane. Feasibility of the method was investigated by Monte Carlo simulation.