Cross-section induced uncertainties in neutron source mission rate calculations
Main Article Content
Abstract
Analysis presented in the paper is focused on the characterization of uncertainties induced by cross-section data, which contributing to the overall uncertainty of the correction factors. Advances in computational methods and computational power shifted the calculation of correction factors among the standard steps of the manganese bath method what decrease an interest about this part of the method. Anyway, with the development of computational tools, the cross-section data were also improved, and new evaluations of nuclear data libraries include more information about the cross-section data covariances. Therefore, the propagation of uncertainties induced by neutron cross-sections can be carried out within standard transport calculation of the manganese sulphate bath model. In this paper, the super-sequence SAMPLER module that implements stochastic techniques is used to assess the uncertainty in computed results. Reaction rates on all nuclides of the solution are computed in 400 cases with uncertain parameters and the results are evaluated by an auxiliary tool. Consideration of nuclear data uncertainty in calculations is a general trend that requires the attention of nuclear researchers and should draw attention in metrology. Additional 1.5 % (one-sigma) uncertainty is introduced to the overall uncertainty through correction factor.
Article Details
Keywords
cross-section uncertainties, neutron source, emission rate, manganese sulphate bath, SAMPLER
References
[2]. Roberts, N. J. “MCNP Calculations of Correction Factors for Radionuclide Neutron Source Emission Rate Measurements using the Manganese Bath”, Report, Centre for Ionizing Radiation Metrology, Teddington, (2001).
[3]. Wieselquist, W. A., et al., “SCALE Code System”, ORNL/TM-2005/39, Version 6.2.4, Oak Ridge National Laboratory, Oak Ridge, TN, (2020).
[4]. M. B. Chadwick, M. Herman, P. Obložinský et al., “ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data”, Nucl. Data Sheets, 112, 2887-2996 (2011).
[5]. A. Jimenez-Carrascosa, O. Cabellos, C. J. Diez, N. Garcia-Herranz, ”Processing of JEFF nuclear data libraries for the SCALE Code System and testing with criticality experiments,” in Spanish Nuclear Society Annual Meeting, Granada, Spain (October 2021).
[6]. Plompen, A.J.M., Cabellos, O., De Saint Jean, C. et al., “The joint evaluated fission and fusion nuclear data library, JEFF-3.3”, Eur. Phys. J., A 56, 181 (2020).