Statistical approaches to the even-odd effect in fission

Statistical approaches have been widely used for describing the nuclear-fission process. They were quite successful in explaining several prominent features of the global nuclide distributions and many other aspects, while there are controversial conclusions on the origin of the even-odd effect in the nuclear-charge yields. We analyze the ingredients of the main statistical approaches to the even-odd effect in fission and show up that many of their deficiencies rely on unrealistic assumptions. Finally, we demonstrate that the large body of experimental results, obtained in the recent years to a great part at GSI, Darmstadt, is very successfully reproduced by a new stringent statistical approach. (authors)