Cold (Neutronless) Alpha Ternary Fission of 252Cf: Theory and Comparison with Experiment

Abstract

A new phenomenon is studied: the cold (neutronless) ternary α-accompanied fragmentation of 252Cf. The corresponding isotopic yields were calculated as the ratio of the penetrability of a given fragmentation over the sum of penetrabilities of all possible (neutronless) α-ternary fragmentations. No preformation factors were considered. We considered that close to the scission configuration the nucleons of the alpha particle form a small neck. At a given value of the neck radius a double scission takes place and a third light fragment is formed between the two heavier fragments. The corresponding barriers between the light and heavy fragment and between the alpha particle and the two heavier fragments were evaluated by using a double folding potential generated by M3Y nucleon-nucleon forces and realistic fragment ground state deformations. The relative calculated isotopic yields greater than 2 × 10-3 have been observed experimentally for the partners with known spectra. We predict that fragmentations with unknown light partners 105,106Zr, 109,110Mo and 114Ru to be identified in the present data.