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Stability of the Heaviest Nuclei on Spontaneous-Fission and Alpha-Decay

A. Staszczak·Z. Lojewski·A. Baran·B. Nerlo-Pomorska·K. Pomorski
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Abstract

Spontaneous-fission half-lives of the heaviest even-even nuclei are evaluated and compared with their alpha-decay mode. Calculations of spontaneous-fission half-lives are performed in the dynamical way with potential energy obtained by the macroscopic-microscopic method and the inertia tensor obtained by the cranking approximation. The alpha-decay half-lives are calculated for the same region of nuclei by use of the Viola and Seaborg formula. The ground-state properties such as mean square radii and electric quadrupole moments are also studied. From the analysis of spontaneous-fission half-life values it is found that a peninsula of deformed metastable superheavy nuclei near Z=106 and N=162 is separated from an island of the spherical superheavy, around the doubly magic nucleus with Z=114 and N=184, by a trench in the vicinity of neutron number N=170.

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A. Staszczak, Z. Lojewski, A. Baran, B. Nerlo-Pomorska, K. Pomorski. 1996-09-30. Stability of the Heaviest Nuclei on Spontaneous-Fission and Alpha-Decay. https://arxiv.org/abs/nucl-th/9609065

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