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Beta-decay rates of r-process nuclei in the relativistic quasiparticle random phase approximation

T. Niksic·T. Marketin·D. Vretenar·N. Paar·P. Ring
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Abstract

The fully consistent relativistic proton-neutron quasiparticle random phase approximation (PN-RQRPA) is employed in the calculation of beta-decay half-lives of neutron-rich nuclei in the N$\approx$50 and N$\approx$82 regions. A new density-dependent effective interaction, with an enhanced value of the nucleon effective mass, is used in relativistic Hartree-Bogoliubov calculation of nuclear ground states and in the particle-hole channel of the PN-RQRPA. The finite range Gogny D1S interaction is employed in the T=1 pairing channel, and the model also includes a proton-neutron particle-particle interaction. The theoretical half-lives reproduce the experimental data for the Fe, Zn, Cd, and Te isotopic chains, but overestimate the lifetimes of Ni isotopes and predict a stable 132Sn.

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T. Niksic, T. Marketin, D. Vretenar, N. Paar, P. Ring. 2004-12-08. Beta-decay rates of r-process nuclei in the relativistic quasiparticle random phase approximation. https://doi.org/10.1103/physrevc.71.014308

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