²⁵²Cf yield calibration method for nuclear material accountancy and safeguards practitioners

Journal Article · Mon Aug 28 00:00:00 EDT 2023 · Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment

DOI:https://doi.org/10.1016/j.nima.2023.168648· OSTI ID:1998124

Lockhart, Madeline L. ^[1]; Henzlova, Daniela ^[2]; Burr, Thomas L. ^[2]; Croft, Stephen ^[3]; Favalli, Andrea ^[4]

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1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); North Carolina State University, Raleigh, NC (United States)
2. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
3. Lancaster University (United Kingdom)
4. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); European Commission, Ispra (Italy). Joint Research Centre (JRC)

Californium-252 is an isotope commonly encapsulated as a physically small but strong spontaneous fission neutron source for applications in industry, academia, and research. Within the nuclear safeguards community, a well-characterized ²⁵²Cf source is often used as an accessible alternative for plutonium in calibrations measurements, which require the absolute source strength. Current methods of source strength quantification can provide an accurate estimate, approximately 1% uncertainty under optimal conditions, but are typically costly and time consuming. An alternative method was developed to determine ²⁵²Cf source strength using passive neutron correlation counting (PNCC). The PNCC method enables institutions and facilities to perform ²⁵²Cf source calibration measurements in-house using detection systems that are common within the nuclear safeguards community. This novel method was previously successfully demonstrated using neutron multiplicity well counters. However, the previous evaluation utilized detection systems with high neutron detection efficiencies, greater than 60%. The purpose of the current study is to extend the previous evaluation and demonstrate the feasibility of the PNCC ²⁵²Cf calibration method for suite of coincidence counters with lower neutron detection efficiencies, between 15% and 35%, which are more commonly encountered in the field, as well as to provide a step-by-step guide to using the method. The neutron source used in this evaluation was previously certified by the National Institutes of Science and Technology (NIST), which provides a reference for the accuracy of the PNCC method. In conclusion, the present source yield calculations demonstrate excellent agreement with a NIST calibration technique and achieve a standard uncertainty below the target 1%.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 1998124
• Alternate ID(s): OSTI ID: 2369058
• Report Number(s): LA-UR-22--30324
• Journal Information: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, Journal Name: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment Vol. 1056; ISSN 0168-9002
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
Californium-252
material accountancy
neutron detection
passive neutron correlation counting
safeguards
source strength