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Home / Publications / Journals / Nuclear Science and Engineering / Volume 183 / Number 2

Sensitivity of Cross Sections to Isotopic Densities for Subgroup Resonance Self-Shielding Calculations

M. Dion, G. Marleau

Nuclear Science and Engineering / Volume 183 / Number 2 / June 2016 / Pages 261-274

Technical Paper /

First Online Publication:May 20, 2016
Updated:June 6, 2016

The sensitivity coefficients of self-shielded cross sections to isotopic densities are computed for a subgroup resonance self-shielding model. The method we propose is based on the derivatives of the collision probabilities used in the slowing-down equation. In this work, we look at how the sensitivities vary as a function of the position inside a fuel pin or of the position of a fuel pin within an assembly. Moreover, we evaluate the importance of the superhomogenization factors, used to correct self-shielded cross sections for the subgroup method, on the cross-section sensitivities. We also present a comparison with the Monte Carlo code Serpent where the sensitivity coefficients are approximated using a finite difference method.

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