Important Remarks on Latest Multigroup Libraries

Abstract

We have already pointed out that the background cross sections and weighting flux are not adequate in the multigroup library VITAMIN-B6. Here we examine whether the latest multigroup libraries, VITENEA-J, VITJEFF31.BOLIB, MATJEFF31.BOLIB, V7-200N47G in SCALE6, MATXS file in ADS-2.0, HILO2k and MATXSLIB-J33, have the same problems or not. The followings are found out from simple benchmark calculations with ANISN; 1) MATXSLIB-J33 has no problem, 2) VITENEA-J, VITJEFF31.BOLIB, V7-200N47G in SCALE6 and HILO2k are produced by using an inadequate weighting flux, 3) VITJEFF31.BOLIB, MATJEFF31.BOLIB and MATXS file in ADS-2.0 have insufficient background cross section data. It is noted that the self-shielding correction in VITENEA-J, VITJEFF31.BOLIB, MATJEFF31.BOLIB, V7-200N47G in SCALE6, MATXS file in ADS-2.0 and HILO2k is not always adequate, which can lead to unexpected results.

Production and testing of the ENEA-Bologna VITJEFF32.BOLIB (JEFF-3.2) multi-group (199 n + 42 γ) cross section library in AMPX format for nuclear fission applications

“…The 1.0E-06 value was chosen as near as possible to 0.0 (in line with the values used in the past for getting close to 0.0), according to the previously generated OECD-NEADB VITAMIN-J [23] library. Concerning then the 0.01 value, it is underlined that this additional V 0 numerical value improves further (see [24]), for example, the neutron cross section self-shielding of Fe-56 in natural iron and of Co-59 (only isotope in natural cobalt), through a more precise self-shielding factor interpolation. Thermal scattering cross sections were produced for six additional bound nuclides which were processed at all the temperatures available in the JEFF-3.2 thermal scattering law data file which is the same as the ones included in the JEFF-3.…”