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DOE OSTI · 2439170

Analytic Sensitivity Coefficients for General Multigroup Infinite Medium k-Eigenvalue Problems

Weaver, Colin Andrew·Rising, Michael Evan·Kulesza, Joel A.·Perfetti, Christopher Michael·Vaquer, Pablo Andres
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Abstract

This work presents a general set of equations that can be used to rapidly generate new benchmarks to verify nuclear data sensitivity calculations. The general multigroup infinite medium k-eigenvalue neutron transport equation is used to derive analytic expressions for the infinite medium k-eigenvalue, the scalar neutron flux and adjoint flux, and the sensitivity of k∞ to perturbations in the multigroup nuclear data of a single species, isotropic and elastic scattering, material. The multigroup nuclear data for U-235 and U-238 is presented along with their corresponding k-eigenvalues, forward flux, adjoint flux, and sensitivity profiles, which include the sensitivity of k∞ to the total, fission, capture, and scattering macroscopic cross sections as well as to the group-to-group scattering cross section matrix, group-wise fission neutron production, and the unconstrained and constrained fission neutron energy distribution.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSAnalyticInfinite Mediumk-eigenvalueMulitgroupNuclear Criticality Safety Program (NCSP)Sensitivity Coefficient

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Weaver, Colin Andrew, Rising, Michael Evan, Kulesza, Joel A., Perfetti, Christopher Michael, Vaquer, Pablo Andres. 2024-04-21. Analytic Sensitivity Coefficients for General Multigroup Infinite Medium k-Eigenvalue Problems. https://www.osti.gov/biblio/2439170

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