info:eu-repo/semantics/article
Perturbation scheme for estimating uncertainties in thermal scattering cross sections of water
Fecha
2018-11Registro en:
Maul, Lance; Marquez Damian, Jose Ignacio; Braoudakis, George; Ho, Mark; Yeoh, Guan Heng; Perturbation scheme for estimating uncertainties in thermal scattering cross sections of water; Pergamon-Elsevier Science Ltd; Annals of Nuclear Energy; 121; 11-2018; 232-249
0306-4549
CONICET Digital
CONICET
Autor
Maul, Lance
Marquez Damian, Jose Ignacio
Braoudakis, George
Ho, Mark
Yeoh, Guan Heng
Resumen
Neutron-moderator scattering interactions in the thermal energy range are often treated with specialised cross section data derived from the Thermal Scattering Law S(α,β). This scattering law is calculated based on theoretical and experimental models that describe the structure and dynamics of the principle moderator molecule. In this work, a perturbation scheme based on the Total Monte Carlo method is described and the uncertainties of the parameters used to calculate S(α,β) for H in H2O and D and O in D2O from the ENDF/B-VIII.0 library were estimated and propagated through to the cross sections and to an integral criticality scenario in the OPAL Reactor, Sydney Australia, using the transport code Serpent. The calculated uncertainties in the total cross sections are in reasonable agreement with experimental data and provide a basis for future model refinement; uncertainties in several parameters used in the LEAPR of NJOY were identified as critical to specific energy regions and behaviours of the total cross sections. The effect on criticality of these uncertainties was found to be 48 pcm and 41 pcm for H2O and D2O, respectively, within the OPAL Reactor during a low-power configuration.