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DOE OSTI · 1227409

Model development and data uncertainty integration

Swinhoe, Martyn Thomas
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Abstract

The effect of data uncertainties is discussed, with the epithermal neutron multiplicity counter as an illustrative example. Simulation using MCNP6, cross section perturbations and correlations are addressed, along with the effect of the 240 Pu spontaneous fission neutron spectrum, the effect of P(ν) for 240 Pu spontaneous fission, and the effect of spontaneous fission and (α,n) intensity. The effect of nuclear data is the product of the initial uncertainty and the sensitivity -- both need to be estimated. In conclusion, a multi-parameter variation method has been demonstrated, the most significant parameters are the basic emission rates of spontaneous fission and (α,n) processes, and uncertainties and important data depend on the analysis technique chosen.

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46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTIONALPHA REACTIONSCOMPOUND-NUCLEUS REACTIONSCOMPUTERIZED SIMULATIONCORRELATIONSCROSS SECTIONSDATA COVARIANCESDISTURBANCESEMISSIONEPITHERMAL NEUTRONSHE-3 COUNTERSMULTIPLICITYNEUTRON SPECTRAPLUTONIUM 240PLUTONIUM DIOXIDESENSITIVITYSPONTANEOUS FISSIONVARIATIONAL METHODS

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Swinhoe, Martyn Thomas. 2015-12-02. Model development and data uncertainty integration. https://doi.org/10.2172/1227409

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