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arXiv · 1305.5387

Nuclear $\beta^+$/EC decays in covariant density functional theory and the impact of isoscalar proton-neutron pairing

Z. M. Niu·Y. F. Niu·Q. Liu·H. Z. Liang·J. Y. Guo
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Abstract

Self-consistent proton-neutron quasiparticle random phase approximation based on the spherical nonlinear point-coupling relativistic Hartree-Bogoliubov theory is established and used to investigate the $\beta^+$/EC-decay half-lives of neutron-deficient Ar, Ca, Ti, Fe, Ni, Zn, Cd, and Sn isotopes. The isoscalar proton-neutron pairing is found to play an important role in reducing the decay half-lives, which is consistent with the same mechanism in the $\beta$ decays of neutron-rich nuclei. The experimental $\beta^+$/EC-decay half-lives can be well reproduced by a universal isoscalar proton-neutron pairing strength.

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Z. M. Niu, Y. F. Niu, Q. Liu, H. Z. Liang, J. Y. Guo. 2013-05-23. Nuclear $\beta^+$/EC decays in covariant density functional theory and the impact of isoscalar proton-neutron pairing. https://doi.org/10.1103/physrevc.87.051303

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