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Entrance channels and alpha decay half-lives of the heaviest elements

G. Royer·K. Zbiri·C. Bonilla
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Abstract

The barriers standing against the formation of superheavy elements and their consecutive $α$ decay have been determined in the quasimolecular shape path within a Generalized Liquid Drop Model including the proximity effects between nucleons in a neck, the mass and charge asymmetry, a precise nuclear radius and the shell effects given by the Droplet Model. For moderately asymmetric reactions double-hump potential barriers stand and fast fission of compact shapes in the outer well is possible. Very asymmetric reactions lead to one hump barriers which can be passed only with a high energy relatively to the superheavy element energy. Then, only the emission of several neutrons or an $α$ particle can allow to reach an eventual ground state. For almost symmetric heavy-ion reactions, there is no more external well and the inner barrier is higher than the outer one.

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G. Royer, K. Zbiri, C. Bonilla. 2004-10-12. Entrance channels and alpha decay half-lives of the heaviest elements. https://doi.org/10.1016/j.nuclphysa.2003.11.010

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