Detection of Special Nuclear Material by means of promptly emitted radiation following photonuclear stimulation

Techniques have been developed to exploit abundant prompt emissions from photonuclear reactions for the identification of special nuclear material (SNM). These enhancements are designed to reduce inspections times and delivered dose in systems which have, historically, relied solely on delayed emissions. Experimental evidence is presented for prompt neutron time-of-flight measurements, neutron/photon correlations in multiple detectors, and novel detector development, specifically LaBr₃ scintillators with new gating and buffering circuits to identify prompt gamma signatures. Significant and specific signatures indicative of the presence of SNM can be distinguished for the prompt neutron time-of-flight experiment and the neutron/photon correlations in multiple detectors.