The neutron dripline in calcium isotopes from a chiral interaction

TL;DR

This paper introduces a new chiral nuclear interaction that accurately models calcium isotopes and predicts the two-neutron dripline at $^{71}$Ca, extending beyond previous theoretical limits.

Contribution

The study develops and validates a novel chiral interaction, N$^3$LO$_{ m Texas}$, that improves predictions of calcium isotope stability and the neutron dripline using ab-initio methods.

Findings

The new interaction reproduces nuclear properties across a wide mass range.

It predicts the calcium two-neutron dripline at $^{71}$Ca.

The interaction accurately models nuclear matter near saturation.

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.