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arXiv · 2101.07102

Diffuseness parameter as a bottleneck for accurate half-life calculations

Abstract

An investigation of the calculated $α$ decay half-lives of super heavy nuclei (SHN) reveals that the diffuseness parameter is a great bottleneck for achieving accurate results and predictions. In particular, when universal proximity function is adopted for nuclear potential, half-life is found to vary significantly and nonlinearly as a function of diffuseness parameter. To overcome this limiting hurdle, a new semiempirical formula for diffuseness that is dependent on charge and neutron numbers is proposed in this work. With the model at hand, half-lives of 218 SHN are computed, for 68 of which there exists available experimental data and 150 of which are predicted. The calculations of half-lives for 68 SHN are compared against experimental data and the calculated data obtained by using deformed Woods-Saxon, deformed Coulomb potentials model, and six semiempirical formulas. The predictions of 150 SHN are compared against the predictions of seven of the current best semiempirical formulas. Calculations of the present study are in good agreement with the experimental half-lives outperforming all but ImSahu semiempirical formula. Moreover, the predictions of our model are consistent with predictions of the semiempirical formulas. We strongly conclude that more attention should be directed toward obtaining accurate diffuseness parameter values for using it in nuclear calculations.

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Aladdin Abdul-latif, Omar Nagib. 2021-01-18. Diffuseness parameter as a bottleneck for accurate half-life calculations. https://doi.org/10.1103/physrevc.100.024601

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