https://doi.org/10.1140/epjp/s13360-022-02865-7
Regular Article
Nuclear data evaluation for decay heat analysis of spent nuclear fuel over 1–100 k year timescale
1
James Watt School of Engineering, University of Glasgow, G12 8QQ, Glasgow, UK
2
Scottish Universities Environmental Research Centre, G75 0QF, East Kilbride, UK
a
h.doran.1@research.gla.ac.uk
Received:
26
February
2022
Accepted:
22
May
2022
Published online:
6
June
2022
Accurate nuclear data are essential in the evaluation of decay heat from spent nuclear fuel (SNF). The accuracy of such data was assessed using an approach that compares values reported in different evaluated libraries and determines whether discrepancies reflect inaccuracies in primary data. A short list of 43 isotopes which are most significant to SNF decay heat calculations over 1–100 k years was produced by combining generic reactor inventory code with decay heat analysis for undifferentiated SNF. Decay properties (half-lives and decay energies) and neutron interactions (cross section and fission yields) were compared from 6 evaluated libraries. Fission product (FP) discrepancies identified are 90Sr half-life, where inclusion of a single measurement significantly reduces the evaluated value; 95mNb beta energy, where DDEP evaluation omits the decay to the 95Mo ground state; 99Tc beta energy, where evaluations differ by approximately 10% with a variety of shape factors used; 126Sb/126mSb beta (JEF2.2/3.1.1/3.3) and electron energies (JEFF3.1.1), where intensity differences are reported; and 137Cs beta energy, where ENDF/B-VIII.0 and JEF3.3 evaluations use incorrect shape factors. For actinides, the major discrepancies identified were 237Np alpha energy (JEF2.2/3.1.1) and 225Ac electron energies (ENDF/B-VIII.0) but overall show less discrepancies during long-term disposal (0.1–100 ky) compared to FP’s during interim storage (1–100 years). Further assessments of the 90Sr half-life and the best shape factor for the 99Tc beta decay are needed to improve future decay heat analyses, which are important for designing future stores and evaluating schemes for possible heat recovery.
© The Author(s) 2022
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
