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Predictions of $alpha$ decay half-lives for even-even superheavy nuclei with $104 leqslant Z leqslant 128$ based on two-potential approach within cluster-formation model

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 نشر من قبل Xiao-Hua Li
 تاريخ النشر 2020
  مجال البحث
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In present work, we systematically study the $alpha$ decay half-lives of 170 even-even nuclei with $60 leqslant Z leqslant 118$ within the two-potential approach while the $alpha$ decay preformation factor $P_alpha$ is obtained by the cluster-formation model. The calculated results can well reproduce the experimental data. In addition, we extend this model to predict the $alpha$ decay half-lives of 64 even-even nuclei with $104 leqslant Z leqslant 128$ whose $alpha$ decay is energetically allowed or observed but not yet quantified. For comparing, the two famous models i.e. SemFIS proposed by D. Poenaru ${et al.}$ [href {https://doi.org/10.1209/0295-5075/77/62001}{Europhys. Lett. textbf{77} (2007) 62001}] and UDL proposed by C. Qi ${et al.}$ [href {https://doi.org/10.1103/PhysRevLett.103.072501}{Phys. Rev. Lett. textbf{103} (2009) 072501}] are used. The predicted results of these models are basically consistent. At the same time, through analyzing the changing trend of $alpha$ decay energy $Q_{alpha}$ of emph{Z} = 118, 120, 122, 124, 126 and 128 isotopes nuclei with the increasing of neutron number emph{N} and that of $alpha$ decay preformation factor $P_alpha$ of those isotopes even-even nuclei with the increasing of neutron number emph{N}, emph{N} = 178 may be a new neutron magic number.

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