Simplified Simulation of Fast Neutron Scattering for an Explosives Detection Application

In developing applications for fast neutron scattering in explosives detection, Monte Carlo simulations were completed that characterized the scattering behavior of fast neutrons in a simplified geometry. Targets included C, N, O, and Fe, as well as air, water, oil, and the explosive RDX (C3H6N6O6). Work included a study of energy binning, particle histories, and statistical uncertainty. Results of the simulations closely matched expected scatter behavior. Energy bins of 0.2 MeV and 1 × 10⁸ particle histories provided ample statistical certainty.