"ISINN-32" Empirical predictions of $\alpha$-decay and spontaneous fission half-lives in the decay chains of elements 119 and 120

Abstract The competition between $\alpha$~decay and spontaneous fission in the decay chains of isotopes with $Z = 119$ and $120$ is investigated using empirical formulas. The $\alpha$-decay half-lives are calculated using the Viola--Seaborg semi-empirical formula, while the spontaneous fission half-lives are evaluated using an empirical formula based on the neutron excess $N-Z$ and the $\alpha$-decay energy $Q_\alpha$. The reliability of the approach is validated against experimental data for known nuclei with $Z \ge 103$. A number of $\alpha$-decay chains are identified as promising for experimental observation, with six or more consecutive $\alpha$~decays expected before termination by spontaneous fission. The present results may be of interest for future experimental searches for superheavy nuclei.