New Modes of Collinear Cluster Tri-Partition

In our previous publications, we discussed various manifestations of a new decay channel of the low excited heavy nuclei, dubbed collinear cluster tri-partition (CCT). The most populated CCT mode was revealed in the mass correlation distribution of fission fragments as a local region (‘‘bump’’) of increased yields below the loci linked to the conventional binary fission. The bump was named ‘‘Ni-bump’’ because it is centered at the masses associated with the magic isotopes of Ni. In the new experiment, we have modified essentially hardware and software used in our previous experiments. New experimental data were obtained for the ^235 U( γ,f ) reaction. The results complement our knowledge about the CCT mechanism, in particular its relationship with the shape isomer states in fission fragments.