Microscopic cold fission yields ofCf252

Abstract

We show that the sharp maximum corresponding to $^{107}\mathrm{Mo}$ in the fragment distribution of the $^{252}\mathrm{Cf}$ cold fission is actually a Sn-like radioactivity, similar to other decay processes in which magic nuclei are involved, namely $\ensuremath{\alpha}$ decay and heavy cluster emission, also called Pb-like radioactivity. It turns out that the mass asymmetry degree of freedom has a key role in connecting initial Sn with the final Mo isotopes along the fission path. We investigate the cold rearrangement of nucleons within the framework of the two-center shell model in order to compute the cold valleys in the charge equilibrated fragmentation potential. The fission yields are estimated by using the semiclassical penetration approach. We consider 5 degrees of freedom, namely the interfragment distance, the shapes of fragments, the neck parameter, and mass asymmetry. We found an isomeric minimum between the internal and external barriers. It turns out that the inner cold valley of the total potential energy is connected to the doubly magic isotope $^{132}\mathrm{Sn}$.