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arXiv · 2512.17311

From closed shells to open shells: Coupled-cluster calculations of atomic nuclei

F. Marino·F. Bonaiti·P. Demol·S. Bacca·T. Duguet·G. Hagen·G. R. Jansen·T. Papenbrock·A. Tichai
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Abstract

Coupled-cluster theory is a powerful tool for first-principles calculations of atomic nuclei, enabling accurate predictions of nuclear observables across the Segr\`e chart. While coupled-cluster computations are especially efficient at shell closures, extensions have been developed to tackle open-shell nuclei, by exploiting the equation-of-motion method or by expanding the coupled-cluster wave function on top of a symmetry-breaking (either deformed or superfluid) reference state. In this study, we provide a comprehensive comparison of these different formulations applied to the calcium and nickel isotopes using nuclear two- and three-body interactions from chiral effective field theory. Based on ground-state energies, two-neutron separation energies, and two-neutron shell gaps, different coupled-cluster computations - based on symmetry-broken reference states and equation-of-motion techniques - offer consistent descriptions of bulk properties across medium-mass isotopic chains.

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F. Marino, F. Bonaiti, P. Demol, S. Bacca, T. Duguet, G. Hagen, G. R. Jansen, T. Papenbrock, A. Tichai. 2025-12-19. From closed shells to open shells: Coupled-cluster calculations of atomic nuclei. https://doi.org/10.1103/p297-y8vq

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