Programme

O.21 -- Oral, VCTP-51

Date: Tuesday, 4 August 2026

Time: 14:40-15:00

Empirical systematics for spontaneous fission and alpha-decay half-lives of heavy and superheavy nuclei

Moiseev Nikita (1,2), Antonenko Nikolai (1,2), Adamian Gurgen (1)

(1) Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Russia; (2) National Research Tomsk Polytechnic University, 634050 Tomsk, Russia

A systematic analysis of the relationship between spontaneous fission $T_{1/2}^{\mathrm{SF}}$ and $\alpha$-decay $T_{1/2}^{\alpha}$ half-lives is performed for ground-state heavy and superheavy nuclei. The ratio of logarithmic half-lives exhibits a grid-like behavior with respect to proton $Z$ and neutron $N$ numbers and remains nearly constant along $\alpha$-decay chains where the neutron excess $N-Z$ is fixed. This regularity leads to a three-parameter empirical formula linking $T_{1/2}^{\mathrm{SF}}$ directly to $T_{1/2}^{\alpha}$ and $N-Z$. In addition, a linear correlation between $\log_{10} T_{1/2}^{\mathrm{SF}}$ and the $\alpha$-particle separation energy $Q_\alpha$ at fixed $N-Z$ is established, yielding a second formula. Both formulas reproduce experimental spontaneous fission half-lives with mean absolute deviations within one order of magnitude. They are applied to analyze the competition between $\alpha$ decay and spontaneous fission along $\alpha$-decay chains originating from isotopes of elements 119 and 120. The existence of a fundamental relationship between spontaneous fission and $\alpha$-decay processes is discussed.

Presenter: Moiseev Nikita