Over the last decade, ingenuous developments in Monte Carlo methods have enabled unbiased estimation of adjoint-weighted reactor parameters expressed as bilinear forms, such as kinetics parameters and sensitivity coefficients. A prominent example is the Iterated Fission Probability (IFP) method, which relies on the simulation of the fission chains descending from an ancestor neutron: the neutron population at an asymptotic fission generation yields an estimate of the importance function and hence of the adjoint fundamental eigenmode. In this project we establish rigorous results concerning the moments of the asymptotic neutron population. We then propose a simple benchmark configuration where exact solutions are derived for these moments, which can be used for the verification of new functionalities of production Monte Carlo codes involving the IFP method.
Project team: Emma Horton, Andreas Kyprianou, Andrea Zoia (CEA) and Eric Dumonteil (CEA)