Nuclear data-induced uncertainty quantification of prompt neutron decay constant based on perturbation theory for ADS experiments at KUCA. Issue 2 (1st February 2020)

• Record Type: Journal Article
• Authors: Endo, Tomohiro; Watanabe, Kenichi; Chiba, Go; Yamanaka, Masao; van Rooijen, Willem Frederik Geert; Pyeon, Cheol Ho
• Is Part Of: Journal of nuclear science and technology. Volume 57:Issue 2(2020)
• Page Start: 196
• Page End: 204
• Publication Date: 2020-02-01
• Subjects: Prompt neutron decay constant -- KUCA -- ADS -- measurement -- ω-eigenvalue -- sensitivity analysis -- uncertainty quantification; Nuclear engineering -- Periodicals; Nuclear physics -- Periodicals; Nuclear energy -- Periodicals; 621.4805
• DOI: 10.1080/00223131.2019.1647893
• Languages: English
• ISSNs: 0022-3131

Abstract

ABSTRACT: In experimental benchmarks of the accelerator-driven system (ADS) conducted at the Kyoto University Critical Assembly (KUCA), the prompt neutron decay constant α was measured using two types of pulsed neutron sources, i.e. a D-T neutron source and a spallation neutron source driven by a 100-MeV proton beam. The measurement results of α are useful information to validate the numerical results predicted by the prompt ω -eigenvalue calculation. In this study, the numerical analysis of α using a multi-energy group SN neutron transport code was carried out for the uranium-lead zoned experimental cores. To reduce the discretization error owing to the deterministic code, the KUCA geometry was modelled in detail as a three-dimensional heterogeneous plate-by-plate geometry, and an improved variant of EON quadrature was utilized. In addition, the sensitivity coefficients of α with respect to nuclear data were efficiently evaluated by first-order perturbation theory, followed by nuclear data-induced uncertainty quantification based on the 56 neutron-energy group SCALE covariance library. Consequently, the numerical results of α were validated successfully by the experimental results of the pulsed neutron source method, compared with the range of the nuclear data-induced uncertainties.