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arXiv · 1709.03606

Quasiparticle-vibration coupling effects on nuclear transitions of astrophysical interest

Caroline Robin·Elena Litvinova
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Abstract

The relativistic quasiparticle time-blocking approximation (RQTBA) is applied to the description of nuclear excitation modes of astrophysical interest. This method is based on the meson-nucleon Lagrangian and goes beyond the standard relativistic quasiparticle random-phase approximation (RQRPA) by treating the coupling between single quasiparticles and collective vibrations of the nucleus. We calculate electric dipole transitions and Gamow-Teller modes in the (p,n) direction in a few Sn isotopes and obtain the rates of (n,$\gamma$) reaction and $\beta^-$-decay processes, which govern the r-process nucleosynthesis, in a unified RQTBA framework. Gamow-Teller transitions in the (n,p) branch, which in principle can serve for the modeling of stellar evolution, are also investigated, and $^{90}$Zr is taken as a study case.

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Caroline Robin, Elena Litvinova. 2017-09-11. Quasiparticle-vibration coupling effects on nuclear transitions of astrophysical interest. https://doi.org/10.1063/1.5016139

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