Review of JENDL-3 data from viewpoint for FBR benchmark tests

Results of FBR benchmark tests are reviewed. JENDL-3 predicts various FBR characteristics much better than JENDL-2. Particularly C/E values of sodium void coefficients and Doppler coefficients are much improved and space dependences observed with JENDL-2 for reaction rates, sodium void coefficients and control rod worth nearly disappear. On the other hand, it was pointed out that there exist a slight core dependence for effective multiplication factors and overestimation of threshold reaction rates. Concerning these points, the JENDL-3 data were reviewed by comparing the JENDL-2 data. Simultaneous evaluation was adopted for principal actinide nuclides. As a results, fission cross sections of 235U and 239Pu are lower than those of JENDL-2 below a few hundred keV. Lower capture cross section and higher inelastic scattering cross section were adopted for 238U. A harder fission spectrum of Madland-Nix type was assumed. Considering the results of the benchmark tests and the characteristics of the JENDL-3 data. The following can be concluded. The balance of JENDL-3 is much better than that of JENDL-2. The low fission cross sections of 235U and 239Pu and the low capture cross section of 238U seem to be reasonable. On the other hand, further study will be required for the inelastic scattering cross section of 238U and the fission spectrum. (author)