Calculation of Reactor Kinetics Parameters βeff and Λ with Monte Carlo Differential Operator Sampling
Japan Atomic Energy Agency, Nuclear Science and Engineering Directorate, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
The methods to calculate the kinetics parameters of βeff and Λ with the differential operator sampling have been reviewed. The comparison of the results obtained with the differential operator sampling and iterated fission probability approaches has been performed. It is shown that the differential operator sampling approach gives the same results as the iterated fission probability approach within the statistical uncertainty. In addition, the prediction accuracy of the evaluated nuclear data library JENDL-4.0 for the measured βeff/Λ and βeff values is also examined. It is shown that JENDL-4.0 gives a good prediction except for the uranium-233 systems. The present results imply the need for revisiting the uranium-233 nuclear data evaluation and performing the detailed sensitivity analysis.
Key words: Reactor kinetics parameters / Effective delayed neutron fraction / Neutron generation time / Monte Carlo / Differential operator sampling
© Owned by the authors, published by EDP Sciences, 2014