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

The beta-decay half-lives of neutron-rich nuclei with 20 <= Z <= 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 beta-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 greater than or similar to 140, an important result for the understanding of the origin of heavy elements in the universe. (C) 2013 Elsevier B.V. All rights reserved.