Peculiarities of clusters formation in true ternary fission of ${}^{252}$Cf and ${}^{236}$U${}^{\ast }$

Abstract

The existence of a new type of cluster decay called "collinear cluster tri-partition" (CCT) is discussed by an analysis of the landscape of the potential energy surface (PES). The total energy of the ternary system is found as a sum the binding energies of fragments and nucleus-nucleus interaction between them. The pre-scission state of the ternary system is assumed to be arranged as a chain of the three fragments along a straight line. Minima and valleys of the PES are determined by variation of the proton and neutron distributions between them. Pre-scission prompt emission of neutrons is assumed and PES is calculated for the cases of emission of 2---4 neutrons. The presence of the valley corresponding to the formation of the isotopes of Sn with masses $A$=130---136 is inherent for all PES calculated for CCT for spontaneous fission of ${}^{252}$Cf and fission induced by neutrons of ${}^{235}$U. There are local minima indicating the formation of Ca, Fe, Ni, Ge and Se isotopes having magic proton or/and neutron numbers, such as 20, 28, and 50. The analysis shows that the experimentally observed ${}^{68}$Ni is formed as the edge fragment of the ternary system connecting to Sn by Si and Ca isotopes at fission of ${}^{236}$U and ${}^{252}$Cf, respectively.

13 pages, 6 figures

Cited by in corpus (4)

• Deformation effects in the alpha accompanied cold ternary fission of even-even ${}^{244-260}$Cf isotopes
• A New Radioactive Decay Mode, True Ternary Fission, the Decay of Heavy Nuclei Into Three Comparable Fragments
• Dynamics of the tri-nuclear system at spontaneous fission of ${}^{252}$Cf
• Nuclear shell effect and collinear tripartition of nuclei