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arXiv · 2512.11723

The neutron dripline in calcium isotopes from a chiral interaction

B. S. Hu·A. Ekström·C. Forssén·G. Hagen·W. G. Jiang·T. Miyagi·T. Papenbrock
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Abstract

Interactions derived from effective field theories of quantum chromodynamics have thus far failed to bind calcium nuclei beyond neutron number $N=40$, while nuclear density functionals typically place the neutron dripline near $^{70}$Ca, at $N=50$. We present the chiral interaction N$^3$LO$_{\rm Texas}$, a combination of two- and three-nucleon potentials at fourth and third chiral order, respectively, with low-energy constants optimized using emulator-accelerated fits to few- and many-body data. This interaction accurately reproduces binding energies and charge radii of key nuclei with mass number $A=3$ to $208$, important excited states, and nuclear matter near saturation. Using ab-initio methods, we find that the calcium two-neutron dripline extends to $^{71}$Ca.

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B. S. Hu, A. Ekström, C. Forssén, G. Hagen, W. G. Jiang, T. Miyagi, T. Papenbrock. 2025-12-12. The neutron dripline in calcium isotopes from a chiral interaction. https://arxiv.org/abs/2512.11723

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