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arXiv · 1210.0680

$β$-decay half-lives of neutron-rich nuclei and matter flow in the $r$-process

Z. M. Niu·Y. F. Niu·H. Z. Liang·W. H. Long·T. Nikšić·D. Vretenar·J. Meng
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Abstract

The $β$-decay half-lives of neutron-rich nuclei with $20 \leqslant Z \leqslant 50$ are systematically investigated using the newly developed fully self-consistent proton-neutron quasiparticle random phase approximation (QRPA), based on the spherical relativistic Hartree-Fock-Bogoliubov (RHFB) framework. Available data are reproduced by including an isospin-dependent proton-neutron pairing interaction in the isoscalar channel of the RHFB+QRPA model. With the calculated $β$-decay half-lives of neutron-rich nuclei a remarkable speeding up of $r$-matter flow is predicted. This leads to enhanced $r$-process abundances of elements with $A \gtrsim 140$, an important result for the understanding of the origin of heavy elements in the universe.

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Z. M. Niu, Y. F. Niu, H. Z. Liang, W. H. Long, T. Nikšić, D. Vretenar, J. Meng. 2013-05-24. $β$-decay half-lives of neutron-rich nuclei and matter flow in the $r$-process. https://doi.org/10.1016/j.physletb.2013.04.048

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