ROLE OF FRAGMENT HIGHER STATIC DEFORMATIONS IN THE COLD BINARY FISSION OF Cf

We study the binary cold fission of 252Cf in the frame of a cluster model where the fragments are born to their respective ground states and interact via a double-folded potential with deformation effects taken into account up to multipolarity λ = 4. The preformation factors were neglected. In the case when the fragments are assumed to be spherical or with ground state quadrupole deformation, the Q-value principle dictates the occurence of a narrow region around the double magic 132Sn, like in the case of cluster radioactivity. When the hexadecupole deformation is turned on, an entire mass-region of cold fission in the range 138÷156 for the heavy fragment arise, in agreement with the experimental observations. This fact suggests that in the above mentioned mass-region, contrary to the usual cluster radioactivity where the daughter nucleus is always a neutron/proton (or both) closed shell or nearly closed shell spherical nucleus, the clusterization mechanism seems to be strongly influenced by the hexadecupole deformations rather than the Q-value. PACS number : 25.85.Ca,27.90.+b Typeset using REVTEX 1