Effects of Uncertainties in Lead Cross Section Data in Monte Carlo Analysis of lead Cooled and reflected Reactors

This paper describes the problems encountered in the analysis of the Encapsulated Nuclear Heat Source (ENHS) core benchmark and the new cross section libraries developed to overcome these problems. The ENHS is a new lead-bismuth or lead cooled novel reactor concept that is fuelled with metallic alloy of Pu, U and Zr, and is designed to operate for 20 effective full power years without re-fuelling and with very small burn-up reactivity swing. There are numerous uncertainties in the prediction of core parameters of this and other innovative reactor designs, arising from approximations used in the solution of the transport equation, in nuclear data processing and cross section libraries generation. In this paper we analyzed the effects of uncertainties in lead cross sections data from several versions of ENDF, JENDL and JEFF for lead-cooled and reflected computational benchmarks. (author)