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DOE OSTI · 23047491

Second-Order Uncertainty Analysis for Radiation Shielding Problems Using MCNP

Favorite, Jeffrey A.·Burr, Tom
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Abstract

Standard uncertainty propagation is based on a first-order Taylor expansion. This approximation is usually justified by assuming that 'uncertainties are very small numbers compared with the values of their corresponding quantities'. Furthermore, the second derivatives needed for a second-order analysis are not usually available, and a second-order analysis requires more knowledge regarding the distribution of the random variables. For radiation shielding problems, the MCNP6 Monte Carlo code computes first and second derivatives of a response with respect to nuclide density or reaction cross section. This paper explores the application of these derivatives to second-order uncertainty analysis.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGCOMPUTERIZED SIMULATIONCROSS SECTIONSDENSITYISOTOPESMONTE CARLO METHODNEUTRON TRANSPORTRANDOMNESSSHIELDING

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Favorite, Jeffrey A., Burr, Tom. 2017-07-01. Second-Order Uncertainty Analysis for Radiation Shielding Problems Using MCNP. https://www.osti.gov/biblio/23047491

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