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

D. N. Poenaru; R. A. Gherghescu

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arXiv · 1706.04068

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

D. N. Poenaru·R. A. Gherghescu

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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.

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D. N. Poenaru, R. A. Gherghescu. 2017-06-10. Alpha decay of nuclei interesting for synthesis of $Z=119, 120$ isotopes. https://arxiv.org/abs/1706.04068

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