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DOE OSTI · 1898325

Data Assimilation using Non-invasive Monte Carlo Sensitivity Analysis of Reactor Kinetics Parameters [Slides]

Kleedtke, Noah·Hutchinson, J.·Cutler, T.·Michaud, I.·Rising, M.·Hua, M.·Alwin, J.·Grosskopf, M.·Vander Wiel, S.·Neudecker, D.·Thompson, N.
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Abstract

Sensitivity coefficients of prompt neutron decay constant (α) and effective delayed neutron fraction (β eff ) to Pu-239 nuclear data were calculated using a newly available tool (ACEtk). Uncertainty calculations showed the following trends: (1) The prompt neutron decay constant can be used to reduce nuclear data-induced uncertainty in Pu-239(n,f) and (2) the effective delayed neutron fraction can be used to effectively reduce nuclear data-induced uncertainty in Pu-239 total fission $\tilde{v}$. Sensitivity/uncertainty analysis can be used to determine optimal experiment/detector setup to identify compensating errors in nuclear data. Upcoming work includes investigating other nuclide-reaction pairs and response sensitivities, such as Δ$\rho$, neutron leakage spectra, and reaction rate measurements to constrain nuclear data of interest.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSExperiments Underpinned by Computational Learning for Improvements in nuclear Data (EUCLID)Integral ExperimentsNuclear Criticality Safety Program (NCSP)Prompt Neutron Decay Constant

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Kleedtke, Noah, Hutchinson, J., Cutler, T., Michaud, I., Rising, M., Hua, M., Alwin, J., Grosskopf, M., Vander Wiel, S., Neudecker, D., Thompson, N.. 2022-07-27. Data Assimilation using Non-invasive Monte Carlo Sensitivity Analysis of Reactor Kinetics Parameters [Slides]. https://doi.org/10.2172/1898325

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