An automated delayed neutron counting system for mass determinations of special nuclear materials


An automated delayed neutron counting (DNC) system has been developed at the Royal Military College of Canada (RMC) to enhance nuclear forensics capabilities pertaining to special nuclear material analysis. The system utilises the SLOWPOKE-2 Facility at RMC as a neutron source and 3He detectors. System control and data acquisition occur through a LabVIEW platform. The time dependent count rate of the delayed neutron production has been examined for 235U, using certified reference materials. Experimental validation according to ISO 17025 protocols suggests typical errors and precision of −3.6 and 3.1%, respectively, and a detection limit of 0.26 μg 235U.

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Financial support has been provided by the Director General of Nuclear Safety, the Analytical Sciences Group and the SLOWPOKE-2 Facility at the Royal Military College of Canada. The authors would like to thank Dave Ferguson, John Shaw, Matthew Mackay, Kathy Nielsen and Kristine Mattson for their assistance.

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Correspondence to E. C. Corcoran.

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Sellers, M.T., Kelly, D.G. & Corcoran, E.C. An automated delayed neutron counting system for mass determinations of special nuclear materials. J Radioanal Nucl Chem 291, 281–285 (2012).

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  • Delayed neutron counting
  • Nuclear forensics
  • Special nuclear materials