Portable Neutron Coincidence Counter

1996PDFTech ReportPNNL-11415DE-AC06-76RLO 1830DesignDetection and identificationNeutron activation analysisPerformance testsTables (Data)NeutronsCoincidence MethodsExperimental DataFissile MaterialsHe-3 CountersNeutron DetectionPerformance TestingUnited StatesWashingtonPacific Northwest National LaboratoryPeurrung, A. J.Bowyer, S. M.Craig, R. A.Dudder, G. B.Knopf, M. A.Panisko, M. E.Reeder, P. L.Stromswold, D. S.Sunberg, D. S.Pacific Northwest National LaboratoryUnited States. Dept. of EnergyUS Transportation CollectionPacific Northwest National Laboratory has designed and constructed a prototype portable neutron coincidence counter intended for use in a variety of applications, such as the verification and inspection of weapons components, safety measurements for novel and challenging situations, portable portal deployment to prevent the transportation of fissile materials, uranium enrichment measurements in hard-to-reach locations, waste assays for objects that cannot be measured by existing measurement systems, and decontamination and decommissioning. The counting system weighs less than 40 kg and is composed of parts each weighing no more than 5 kg. In addition, the counter's design is sufficiently flexible to allow rapid, reliable assembly around containers of nearly arbitrary size and shape. The counter is able to discern the presence of 1 kg of weapons-grade plutonium within an ALR-8 (30-gal drum) in roughly 100 seconds and 10 gin roughly 1000 seconds. The counter's electronics are also designed for maximum adaptability, allowing operation under a wide variety of circumstances, including exposure to gamma-ray fields of 1 R/h. This report provides a detailed review of the design and construction process. Finally, preliminary experimental measurements that confirm the performance capabilities of this counter are discussed.81