STATUS OF FISSION YIELD DATA
Centre d'Etudes Nucleaires et ISN
85X-F 38041 Grenoble Cedex, France
Los Alamos National Laboratory
Los Alamos, New Mexico 87545 USA
In this paper first we summarize the current status of the US evaluation for 34 fissioning nuclides at one or more neutron incident energies and for spontaneous fission. Currently there are 50 yields sets, and for each we have independent and cumulative yields and uncertainties for approximatively 1100 fission products. When finalized the recommended data will become part of the next version of the US ENDF/B-VI. In a second part we review the different models developed to derive independent yields sets. The Zp and empirical models have been extensively studied by A.C. Wahl for 6 fissioning nuclides. Comparison of model estimates with experimental data will be presented. The parameters for other fissioning systems will be derived by the use of systematic trends. A comparison of model estimates with some recent experimental data, obtained from Lohengrin (249Cf T) will be given.
KEYWORDS: Fission, Fragment yields, Fragment charge distribution, Evaluation