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arXiv · 1512.05845

Correlations between neutrons and protons near Fermi surface and $Q_α$ of super-heavy nuclei

Ning Wang·Min Liu·Xizhen Wu·Jie Meng
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Abstract

The shell corrections and shell gaps in nuclei are systematically studied with the latest Weizsäcker-Skyrme (WS4) mass model. We find that most of asymmetric nuclei with (sub)-shell closures locate along the shell stability line (SSL), $N=1.37Z+13.5$, which might be due to a strong correlation between neutrons and protons near Fermi surface. The double magicity of nuclei $^{46}$Si and $^{78}$Ni is predicted according to the corresponding shell gaps, shell corrections and nuclear deformations. The unmeasured super-heavy nuclei $^{296}$118 and $^{298}$120, with relatively large shell gaps and shell corrections, also locate along the SSL, whereas the traditional magic nucleus $^{298}$Fl evidently deviates from the line. The $α$-decay energies of super-heavy nuclei with $Z=113-126$ are simultaneously investigated by using the WS4 model together with the radial basis function corrections. For super-heavy nuclei with large shell corrections, the smallest $α$-decay energy for elements $Z=116$, 117 and 118 in their isotope chains locates at $N=178$ rather than $184$.

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Ning Wang, Min Liu, Xizhen Wu, Jie Meng. 2015-12-18. Correlations between neutrons and protons near Fermi surface and $Q_α$ of super-heavy nuclei. https://doi.org/10.1103/physrevc.93.014302

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