Trajectory Periods Folding Method for Modeling of Uranium and Thorium Fuel Transmutations

The Continuous Energy Monte Carlo Burnup Code (MCB) is a general-purpose tool dedicated for simulations of radiation transport and radiation-induced changes in matter in any nuclear system. In the recent years the methodology of the trajectory periods folding was integrated with MCB. In the proposed methodology, the mass flow of direct nuclide-to-nuclide transitions leading to nuclide transmutation chains in every step is interpreted over entire period of interest. In this way, all quantitative information about the transmutation process for the period beyond single calculation step is preserved. In the study we present the background of the method as well as its implementation for the modeling of the Lead Cooled Fast Reactor in the adiabatic equilibrium state.