We report in this paper a study in terms of the nuclear shell model about the location of the calcium isotopes drip line. The starting point is considering the realistic two-body potential derived by Entem and Machleidt within chiral perturbation theory at next-to-next-to-next-to-leading order (${\mathrm{N}}^3\mathrm{LO}$), as well as a chiral three-body force at next-to-next-to-leading order (${\mathrm{N}}^2\mathrm{LO}$) whose structure and low-energy constants are consistent with the two-body potential. Then we construct the effective single-particle energies and residual interaction needed to diagonalize the shell-model Hamiltonian. The calculated two-neutron separation energies agree nicely with experiment until ${}^{56}\mathrm{Ca}$, which is the heaviest isotope whose mass has been measured, and do not show any sign of two-neutron emission until ${}^{70}\mathrm{Ca}$. We discuss the role of the choice of the model space in determining the neutron drip line, and also the dependence of the results on the parameters of the shell-model Hamiltonian.

• Received 26 June 2020
• Revised 22 September 2020
• Accepted 6 November 2020

DOI:https://doi.org/10.1103/PhysRevC.102.054326