International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators

4-8 May 2009, Vienna

SM/EN-02

Active Neutron Interrogation to Detect Shielded Fissionable Material

D.L. Chichester and E.H. Seabury

Idaho National Laboratory, Idaho Falls, United States of America

Corresponding Author: david.chichester@inl.gov

Portable electronic neutron generators (ENGs) may be used to interrogate suspicious items to detect, characterize, and quantify the presence fissionable material based upon the measurementof prompt and/or delayed emissions of neutrons and/or photons resulting from fission. The small size ( <0.2 m3), light weight (<12 kg), and low power consumption (<50 W) of modern ENGs makes them ideally suited for use in field situations, incorporated into systems carried by 2 - 3 individuals under rugged conditions. At Idaho National Laboratory we are investigating techniques and portable equipment for performing active neutron interrogation of moderate sized objects less than ~ 2-4 m3 to detect shielded fissionable material. Our research in this area primarily relies upon the use of pulsed deuterium-tritium ENGs and the measurement of die-away prompt fission neutrons in-between neutron bursts. Fissionable materials used for this work include enriched uranium and plutonium in >1 kg quantities. This paper will summarize recent results from our research including descriptions of detectors and interrogation profiles together with a discussion of detection performance evaluations for a variety of shield scenarios.

The authors have assigned to the International Atomic Energy Agency a non-exclusive, royalty-free licence to publish this paper.


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