NEA-1544 ZZ-GEFF-2-MATXS.

ZZ-GEFF-2-MATXS.

This library for fusion neutronics calculations, to be used in conjunction with the TRANSX code, is the MATXS format version of ZZ-GEFF-2-GENDF from which it has been derived by means of the MATXSR NJOY module. It has a 175 neutron, 42 photon VITAMIN-J group structure with the standard weighting function: Maxwellian (at the temperature to which the material is referenced) + 1/E + fission spectrum + 1/E + fusion peak + 1/E. It includes 93 materials from 1-H-1 to Bi-209 - almost all from EFF-2 basic data; but Ag-107, Ag-109, natural Cd, the 6 Hf isotopes and the 4 W isotopes have been taken from JEF-2.2 - at 3 temperatures and 6 dilution cross section values; 10 thermal groups are provided below 3 eV. Neutron cross sections and diffusion matrices, photon and gas production, kerma and DPA are given. The library includes H in H2O, metallic Be and Graphite for which an accurate treatment with S(α,β) matrices has been provided for the thermal scattering region, while all remaining materials have been treated with the 'free gas' approximation.
Photon interaction data are taken from GEPDL - which is included in ZZ-GEFF-2-GENDF - a 42 group photon interaction P8 library based upon EPDL-90; in order to couple this photon section - GEPDL - which is P8, with the neutron part - GEFF-2 - which is P5, the latter has been filled with zeroes for the contribution P6 to P8.

NJOY has been used to process both GEFF-2 and GEPDL; since the processing activities lasted over a couple of years, less important materials were processed with the 91.13 version of the code and the 91.38 has been used to process all the remaining materials, including the whole GEPDL. Some very important modifications have been introduced in the code as far as the kerma computation is concerned, in order to solve problems due to physical inconsistencies of the data and non-standard formats of some materials, e.g. the lump reaction MT 10 - neutron diffusion in the continuum energy region - was not properly treated by the kerma module HEATR. The libraries have been produced both in GENDF - ZZ-GEFF-2-GENDF - and in MATXS format - the current one; the size of this library in card image format is about 500MB.

NJOY, BBC, TRANSX.

• G.C.Panini: Preliminary Report on Group Transport Libraries GEFF-2 RFL-2 from EFF 2.2 > JEF 2.2 at June, 22, 1992 - PART B Graphs - EFF-DOC-154(92)

The SIZE of the library in card image ASCII format is about 500MB. The list of the materials includes the values of temperature and of dilution at which each material is given.

ENEA, Bologna ITALY