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The nuclear shell effects near the r-process path in the relativistic Hartree-Bogoliubov theory

M. M. Sharma·A. R. Farhan
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Abstract

We have investigated the evolution of the shell structure of nuclei in going from the r-process path to the neutron drip line within the framework of the Relativistic Hartree-Bogoliubov (RHB) theory. By introducing the quartic self-coupling of $ω$ meson in the RHB theory in addition to the non-linear scalar coupling of $σ$ meson, we reproduce the available data on the shell effects about the waiting-point nucleus $^{80}$Zn. With this approach, it is shown that the shell effects at N=82 in the inaccessible region of the r-process path become milder as compared to the Lagrangian with the scalar self-coupling only. However, the shell effects remain stronger as compared to the quenching exhibited by the HFB+SkP approach. It is also shown that in reaching out to the extreme point at the neutron drip line, a terminal situation arises where the shell structure at the magic number is washed out significantly.

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M. M. Sharma, A. R. Farhan. 2002-02-09. The nuclear shell effects near the r-process path in the relativistic Hartree-Bogoliubov theory. https://doi.org/10.1103/physrevc.65.044301

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