Continuous-energy perturbation methods in the MORET 5 code
Résumé
The MORET code is a simulation tool that solves the transport equation for neutrons using the Monte Carlo method. A perturbation procedure using first order Taylor expansion series in the continuous-energy calculation for isotopic concentrations and density perturbations have been recently implemented. It relies on the calculation of an adjoint weighted sensitivity coefficient with respect to isotopic concentration. Thus, the MORET code now offers the users the possibility to use either the correlated sampling or taylor series as the perturbation method. The present paper provides a description of continuous-energy perturbation methods available in the MORET code focusing on the Taylor expansion series, which have been implemented in the last release of the code. Then, some considerations about the algorithm and implementation are presented. Finally the verification is presented using several ICSBEP and OECD/NEA benchmarks and some configurations of the French proprietary experimental program MIRTE. © 2017 Elsevier Ltd