Photonuclear-based Explosive Detection System Optimizations

The Idaho National Engineering and Environmental Laboratory (INEEL) has developed a photoneutron‐based nondestructive evaluation (NDE) technique that uses a pulsed, high energy (2‐ to 12‐MeV) electron accelerator and a customized high‐purity germanium‐based gamma‐ray spectroscopy system. This NDE technique is being applied to the detection of nitrogen‐containing explosives. Each pulse of electrons produces highly penetrating bremsstrahlung photons. Interrogating neutrons are generated by the bremsstrahlung photons interacting within a photoneutron source. The interaction of these interrogating neutrons with an object‐of‐interest generates elemental characteristic gamma rays. Spectrometry is performed between accelerator pulses by analyzing these neutron‐capture gamma rays. Calculations have been performed to study the neutron production in the D2O converter and the subsequent 14N neutron capture reactions in the chemical explosive simulant drum, the effectiveness of the neutron reflector and moderator, an...