Symmetric and asymmetric scission properties: Identical shape elongations of fissioning nuclei

The shape elongation β of a fissioning nucleus (of mass A_f) undergoing mass-symmetric and mass-asymmetric deformation is experimentally determined. The results indicate that, either for the mass-symmetric or for the mass-asymmetric deformation, the value of shape elongation is nearly independent of Af and temperature. Three types of shape elongations are observed: The liquid drop property governed mass-symmetric deformation with β ∼ 1.65; the mass-asymmetric deformation with β ∼ 1.53; and the shell influenced mass-symmetric deformation with β ∼ 1.43.