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arXiv · 1312.2189

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

A. K. Nasirov·W. von Oertzen·A. I. Muminov·R. B. Tashkhodjaev
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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.

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A. K. Nasirov, W. von Oertzen, A. I. Muminov, R. B. Tashkhodjaev. 2013-12-08. Peculiarities of clusters formation in true ternary fission of $^{252}$Cf and $^{236}$U$^*$. https://doi.org/10.1088/0031-8949%2F89%2F5%2F054022

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