ENEA-Bologna Production and Testing or JEFF-3.1 Multi-Group Cross Section Libraries for Nuclear Fission Applications

The ENEA-Bologna Nuclear Data Group produced the JEFF-3.1 VITJEFF31.BOLIB and MATJEFF31.BOLIB fine-group coupled neutron and photon (199 n + 42 y) cross section libraries far nuclear fission applications, respectively in AMPX and MATXS format, with the same specifications and energy group structure of the ENDF/B-VI.3 VITAMIN-B6 American library. Each library, containing 181 nuclide cross section files, was generated tram the same set of cross section data files in GENDF format, obtained through the Bondarenko (f-factor) method, with an ENEA-Bologna revised version of the GROUPR module of the NJOY-99.160 system. Collapsed working libraries of self-shielded cross sections in FIDO-ANISN format, used by the deterministic transport codes of the DANTSYS and DOORS systems, can be generated from VITJEFF31.BOLIB and MATJEFF31.BOLIB through, respectively, further data processing with an ENEA-Bologna revised version of the SCAMPI system and with the TRANSX code. This parer describes the methodology and specifications of the data processing performed and presents some results of the VITJEFF31.BOLIB validation.