GENEUS - A Program Designed for Nuclear Data Evaluations

Full text: Nuclear data evaluations merge experimental and theoretical knowledge in order to produce evaluated information which is suitable for the design of novel nuclear technologies and radioactive waste incineration- e.g. accelerator driven system, generation IV reactors, fusion reactors. However, for these applications uncertainty information is of utmost importance, especially for energy ranges with scarce experimental information (beyond 20 MeV). GENEUS (General Nuclear Data Evaluation and Uncertainty System) is a program package which evaluates angle-integrated cross sections for neutron-induced reactions and associated covariance matrices. The program starts out from model cross sections provided by the nuclear model code TALYS-1.0 and prior covariance matrices containing parameter uncertainties and model defects. The former account for the limited knowledge of the parameters of the nuclear model employed and the latter for deficiencies of the model with regard to actually measured values. In few update steps, experimental information, consisting of cross sections as well as covariance matrices is added via the linearized Bayesian Update. The output is given in the ENDF-format, the standard format for nuclear data libraries. The method is illustrated by means of evaluations on Pb-208 and Mn-55. (author)