Cold fission description with constant and varying mass asymmetries

摘要

Different description for varying the mass asymmetry in the fragmentation process are used to calculate the cold fission barrier penetrability. The relevance of the appropriate choice for both the description of the pre- scission phase and inertia coefficient to unify alpha decay, cluster radioactivity, and spontaneous cold fission processes in the same theoretical framework is explicitly shown. We calculate the half-life of all possible partition modes of nuclei of A > 200 following the most recent Mass Table by Audi and Wapstra. It is shown that if one uses the description in which the mass asymmetry is maintained constant during the fragmentation process, the experimental half-life-values and mass yield of (sup 234) U cold fission are satisfactorily reproduced. (author) 39 refs., 6 figs., 2 tabs.; e-mail: telo at ird.gov.br