An International View on 3He Alternatives for Nuclear Safeguards

The U.S. National Nuclear Security Administration NA-241 Office of Nuclear Safeguards and Security hosted a small international workshop of invited experts at Los Alamos National Laboratory on the subject of 3He alternatives for use in international safeguards June 2527, 2013. Specifically, the workshop addressed neutron assay techniques that employ neutron coincidence counters for the verification of declared nuclear materials under safeguards and for monitoring purposes. This article provides in outline a record of the meeting and shares the spirit of the discussions and main observations and recommendations. The scene is a rapidly moving one and so this report only provides a snapshot in time. How the safeguards community will respond to a shortage of 3He for use in neutron detection systems is not yet settled and moving forward we encourage broad participation in formulating both technical and policy options. Particularly perceptions may lag actual capability and there is an opportunity for researchers and developers to engage with the community to ensure decisions are well informed. The workshop concluded that no single technology can replace 3He for all safeguards use cases and that performance metrics need to be re-defined for alternative neutron detection system and concepts of operation. The move from scientific feasibility to proven engineering solution requires a phase of practical demonstration under realistic routine safeguards conditions and many developing alternative technologies are reaching this phase. Well-coordinated demonstration was identified as the best way to move forward. Lastly, challenges associated with Figure-of-Merit definitions and proportional counter high-voltage plateaus were discussed and are addressed in this article. A follow-on workshop was held in the second half of 2014.