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arXiv · 2311.15305

Multireference covariant density-functional theory for the low-lying states of odd-mass nuclei

E. F. Zhou·X. Y. Wu·J. M. Yao
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Abstract

We extend multireference covariant density-functional theory (MR-CDFT) based on a relativistic point-coupling energy functional to describe the low-lying states of odd-mass nuclei. The nuclear wave function is constructed as a superposition of quadrupole-octupole deformed mean-field configurations, with projection onto angular momentum, particle numbers, and parity within the framework of the generator coordinate method. Using $^{25}$Mg as an example, we calculate the energy spectrum, electric multipole, and magnetic dipole transition strengths based on three different schemes for the mean-field configurations of odd-mass nuclei. We find that the low-energy structure of $^{25}$Mg is reasonably reproduced in all three schemes. In particular, the effect of octupole correlation is illustrated in the application to the low-lying parity doublets of $^{21}$Ne. This work demonstrates the success of the MR-CDFT for the low-lying states of odd-mass nuclei with possible strong quadruple-octupole correlations.

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E. F. Zhou, X. Y. Wu, J. M. Yao. 2023-11-26. Multireference covariant density-functional theory for the low-lying states of odd-mass nuclei. https://doi.org/10.1103/physrevc.109.034305

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