Nuclear Theory·nucl-th

Wednesday·April 16, 2025

11 papers—2 primary·9 cross-listed

01
[Submitted on 15 Apr 2025]
Structure and dynamics of open-shell nuclei from spherical coupled-cluster theory
Francesco Marino🇩🇪 · Francesca Bonaiti🇺🇸 · Sonia Bacca🇩🇪 · Gaute Hagen🇺🇸 · Gustav R. Jansen🇺🇸
We extend the spherical coupled-cluster ab initio method for open-shell nuclei where two nucleons are removed from a shell subclosure. Following the recent implementation of the two-particle attached approach [Phys. Rev.C 110 (2024) 4, 044306], we focus on the two-particle-removed method. Using the equations-of-motion framework, we address both nuclear structure and dipole response functions by coupling coupled-cluster theory with the Lorentz integral transform technique. We perform calculations using chiral interactions, including three-nucleon forces, and estimate many-body uncertainties by comparing different coupled-cluster truncation schemes. We validate our approach by studying ground-state energies, excited states, and electric dipole polarizabilities in the oxygen and calcium isotopic chains. For binding energies and selected low-lying excited states, we achieve an accuracy comparable to that of the established closed-shell coupled-cluster theory and generally agree with experiment. Finally, we underestimate experimental data for electric dipole polarizabilities, particularly in calcium isotopes.
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2504.11012 [pdf]
PRC(2025)·10 citations
02
[Submitted on 15 Apr 2025]
Multireference covariant density functional theory for shape coexistence and isomerism in $^{43}$ S
E. F. Zhou · X. Y. Wu · J. Xiang · J. M. Yao · P. Ring
We extend the multireference covariant density functional theory (MR-CDFT) to describe the low-lying states of the odd-mass nucleus $^{43}$ S near the neutron magic number $N = 28$ with shape coexistence. The wave functions of the low-lying states are constructed as superpositions of configurations with different intrinsic shapes and $K$ quantum numbers, projected onto good particle numbers and angular momenta. The MR-CDFT successfully reproduces the main features of the low-energy structure in $^{43}$ S. Our results indicate that the ground state, $3/ 2_{1}^{-}$ , is predominantly composed of the intruder prolate one-quasiparticle (1qp) configuration $ν 1/ 2^{-} [321]$ . In contrast, the $7/ 2_{1}^{-}$ state is identified as a high- $K$ isomer, primarily built on the prolate 1qp configuration $ν 7/ 2^{-} [303]$ . Additionally, the $3/ 2_{2}^{-}$ state is found to be an admixture dominated by an oblate configuration with $K^{π} = 1/ 2^{-}$ , along with a small contribution from a prolate configuration with $K^{π} = 3/ 2^{-}$ . These results demonstrate the capability of MR-CDFT to capture the intricate interplay among shape coexistence, $K$ -mixing, and isomerism in the low-energy structure of odd-mass nuclei around $N = 28$ .
Comments:
7 pages with 3 figure and 1 table
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2504.11244 [pdf]
Nucl.Sci.Tech.(2026)·3 citations

Affiliations

first authorsco-authorsvia INSPIRE

Structure and dynamics of open-shell nuclei from spherical coupled-cluster theory

Multireference covariant density functional theory for shape coexistence and isomerism in 43S

Affiliations

Multireference covariant density functional theory for shape coexistence and isomerism in $^{43}$ S