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arXiv · 2207.01764

Covariant Density Functional Theory with Localized Exchange Terms

Qiang Zhao·Zhengxue Ren·Pengwei Zhao·Jie Meng
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Abstract

A new density-dependent point-coupling covariant density functional PCF-PK1 is proposed, where the exchange terms of the four-fermion terms are local and are taken into account with the Fierz transformation. The coupling constants of the PCF-PK1 functional are determined by empirical saturation properties and ab initio equation of state and proton-neutron Dirac mass splittings for nuclear matter as well as the ground-state properties of selected spherical nuclei. The success of the PCF-PK1 is illustrated with properties of the infinite nuclear matter and finite nuclei including the ground-state properties and the Gamow-Teller resonances. In particular, the PCFPK1 eliminates the spurious shell closures at Z = 58 and Z = 92, which exist commonly in many covariant density functionals without exchange terms. Moreover, the Gamow-Teller resonances are nicely reproduced without any adjustable parameters, and this demonstrates that a self-consistent description for the Gamow-Teller resonances can be achieved with the localized exchange terms in the PCF-PK1. ?

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Qiang Zhao, Zhengxue Ren, Pengwei Zhao, Jie Meng. 2022-07-05. Covariant Density Functional Theory with Localized Exchange Terms. https://doi.org/10.1103/physrevc.106.034315

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