Application of the Fictitious Scattering Radiation Transport Model for Deep-Penetration Monte Carlo Calculations

The fictitious scattering radiation transport model, suitable for Monte Carlo applications in geometrically complex systems, has been extended for use in deep-penetration calculations by the development of an appropriate next-flight estimator. Mathematical derivations are given, and it is shown that the estimation scheme is actually a one-dimensional version of the general model. Sample problems are solved to illustrate the use of the next-flight estimator, its variance characteristics, and the time-saving features of the model. Other items discussed are coupling techniques with standard methods, systems with large cross sections, and inclusion of the fictitious scattering model in multigroup cross-section structure.