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The emission of
$ \alpha $ clusters represents the favored decay mode for most unstable medium mass nuclei, heavy nuclei, and super-heavy nuclei. Since its first experimental observation by Rutherford [1,2], it naturally became one of the standard tools for the study of nuclear structures and reactions and the exclusive way for the identification of new super-heavy nuclei. Moreover, the theoretical interpretation of$ \alpha $ decay as a quantum tunneling effect through a nuclear Coulomb barrier [3] represented a real breakthrough for quantum physics in general, by validating its hypotheses experimentally. The basic experimental observables related to this phenomenon are the$ \alpha $ decay energy$ Q_{\alpha} $ and the associated half-lives$ T_ {\frac {1}{2}} $ . The first notable success of treating$ \alpha $ decay as a semiclassical one-dimensional quantum tunneling process lead to simple but extremely precise correlations relating half-lives,$ Q_{\alpha} $ values, and nucleon numbers through a WKB estimation of the barrier penetration probability. The first correlation of this type was proposed by Geiger and Nuttall [4], which became the basis for various continuously improved empirical formulas for$ \log_{10}T_{\frac {1}{2}} $
Alpha decay of heavy and super heavy nuclei with a generalized electrostatic potential
- Received Date:2020-06-30
- Available Online:2020-12-01
Abstract:Half-lives ofαdecay forZ≥ 84 nuclei are calculated based on the WKB theory applied for a phenomenological potential barrier composed of a centrifugal contribution and a screened electrostatic interaction represented by a Hulthen potential. For favored decays, the model has a single adjustable parameter associated with the screening of the electrostatic potential. The description of half lives for unfavored decays requires an additional hindrance term. A good agreement with experimental data is obtained in all considered cases. The evolution of the screening parameter for each nucleus revealed its dependence on shell filling. The model is also used for theoretical predictions on a few nuclei with uncertain or incomplete decay information.

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