Regular Article

Templates of expected measurement uncertainties

¹ Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
² Naval Nuclear Laboratory, Schenectady, NY, 12301-1072, USA
³ University of California Berkeley, Berkeley, CA, 94720, USA
⁴ U.S. Naval Academy, Annapolis, MD, 21402, USA
⁵ Argonne National Laboratory, Lemont, IL, 60439-4842, USA (retired)
⁶ Lancaster University, Lancaster, LA1 4YW, UK
⁷ National Institute of Standards and Technology, Gaithersburg, MD, 20899-8463, USA
⁸ Pacific Northwest National Laboratory, Richland, WA, 99352, USA
⁹ Helmholtz Centre Dresden Rossendorf, 01328 Dresden, Germany
¹⁰ Uppsala University, 75120 Uppsala, Sweden
¹¹ Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
¹² International Atomic Energy Agency, A-1400 Vienna, Austria
¹³ University of Vienna, A-1010 Vienna, Austria
¹⁴ Duke University, Durham, NC, 27708-0308, USA
¹⁵ Triangle Universities Nuclear Laboratory, Durham, NC, 27708-0308, USA
¹⁶ CEA, DAM, DIF, F-91297 Arpajon, France
¹⁷ Univ. Bordeaux, LP2I, UMR5797, CNRS, F-33170 Gradignan, France
¹⁸ Brookhaven National Laboratory, Upton, NY, 11973-5000, USA
¹⁹ Lawrence Livermore National Laboratory, Livermore, CA, 94551-0808, USA
²⁰ The University of Tennessee Knoxville, Knoxville, Tennessee, 37996, USA
²¹ Université Paris-Saclay, CEA, LMCE, 91680 Bruyères-le-Châtel, France

^* e-mail: dneudecker@lanl.gov

Received: 28 April 2023
Received in final form: 19 July 2023
Accepted: 7 August 2023
Published online: 10 November 2023

Abstract

The covariance committee of CSEWG (Cross Section Evaluation Working Group) established templates of expected measurement uncertainties for neutron-induced total, (n,γ), neutron-induced charged-particle, and (n,xn) reaction cross sections as well as prompt fission neutron spectra, average prompt and total fission neutron multiplicities, and fission yields. Templates provide a list of what uncertainty sources are expected for each measurement type and observable, and suggest typical ranges of these uncertainties and correlations based on a survey of experimental data, associated literature, and feedback from experimenters. Information needed to faithfully include the experimental data in the nuclear-data evaluation process is also provided. These templates could assist (a) experimenters and EXFOR compilers in delivering more complete uncertainties and measurement information relevant for evaluations of new experimental data, and (b) evaluators in achieving a more comprehensive uncertainty quantification for evaluation purposes. This effort might ultimately lead to more realistic evaluated covariances for nuclear-data applications. In this topical issue, we cover the templates coming out of this CSEWG effort–typically, one observable per paper. This paper here prefaces this topical issue by introducing the concept and mathematical framework of templates, discussing potential use cases, and giving an example of how they can be applied (estimating missing experimental uncertainties of ²³⁵U(n,f) average prompt fission neutron multiplicities), and their impact on nuclear-data evaluations.