Monte carlo interpretation of shielding benchmark experiment nesdip and analysis of endf/b-vii.0, jeff-3.1 and jendl-4 iron and water cross sections

The pressure vessel is an important component of the nuclear reactor, the knowledge of the fluence of neutron in this part of the reactor during its operation and their associated effects is a key issue. The calculation method and also the cross section data and their treatment, have an important rule to this problem. For this object the NESDIP benchmark where the neutron transports through typical side-shield of a Pressurized Water Reactor (PWR) were performed at AEA technology Winfrith, UK (United Kingdom). In this study we have been interpreted this benchmark using the Monte Carlo transport code MCNPX for the aim to contribute a validation of the method of calculation, and analyse the cross sections, for Iron (56Fe) and water (1H and 16O), presented by: ENDF/B-VII.0, JEFF-3.1 and JENDL-4 libraries. The continuous energy cross section libraries were produced by the nuclear data processing system NJOY99. The principal results required from the benchmark analysis are the calculated-to-measured (C/M) dosimetry reaction rates of 103Rh (n,n’)103mRh monitor, at different depth in a water/iron shield reproducing the ex-core radial geometry of a PWR. The calculations of the NESDIP benchmark experiment showed us that calculation method is effective for the protection study of the REP. And generally, the average C/M ratios obtained are reasonably good when the uncertainties of the measurements are taken into account. The MCNPX code are choosing on the main are used routinely for studying radiation shielding analysis and the fact that feature a rich palette of Variance Reduction (VR) techniques, which play a very important role to reduce the computer required to obtain results of sufficient precision. Some of these VR techniques have been used in the frame of this protection study such as the energy cut-offs (CUT card), the Geometry splitting and Russian roulette (IMP card) and the phase space.