Direct sensitivity analysis to nuclear data of thorium molten salt reactors at equilibrium using MURE

Abstract

Abstract. In this paper we propose to use the MURE (MCNP Utility for Reactor Evolution) package to calculate directly nuclear data sensitivities of the breeding gain of a thorium molten salt reactor. The continuous fuel reprocessing is used to control reactivity. This control coupled with the fact that the fuel has reached its equilibrium, induces feedback effects on nuclear data sensitivities. That is why sensitivities are calculated directly by recalculating the fuel equilibrium of a simplified model after modifications of the ACE files for the reactions that are expected to have the strongest contribution to the uncertainty: 233U capture cross section and neutron fission yield.