Alpha decay of nuclei interesting for synthesis of $Z=119,120$ isotopes

Abstract

Four groups (even-even, even-odd, odd-even and odd-odd) of heavy and super-heavy nuclei are of interest for the synthesis of the isotopes with $Z=119,120$. We report calculations of $\alpha$~decay half-lives using four models: AKRA (Akrawy); ASAF (Analytical Super-Asymmetric Fission); UNIV (Universal Formula), and semFIS (Semi-empirical formula based on Fission Theory). We compare the experimental $Q_{\alpha }$ values either with AME16 atomic mass evaluation (whenever available) and with the theoretical model WS4, able to give masses of not yet measured nuclides. For ${}^{92,94}$Sr cluster radioactivity of ${}^{300,302}$120 we predict a branching ratio relative to $\alpha$~decay of -0.10 and 0.49, respectively, meaning that it is worth trying to detect such kind of decay modes in competition with $\alpha$~decay.

Comments: 28 pages, 4 figures and 14 tables. arXiv admin note: substantial text overlap with arXiv:1702.05598