Effective field theory for weakly bound two-neutron halo nuclei: Corrections from neutron-neutron effective range
Phys. Rev. C 112, 014001 – Published 7 July, 2025
DOI: https://doi.org/10.1103/lds3-g3tp
Abstract
Using an effective field-theoretical approach, we investigate the properties of weakly bound two-neutron halo nuclei (also known as Borromean nuclei) that do not support a low-energy -wave core-neutron resonance. Extending the recently formulated effective field theory for weakly bound Borromean nuclei, we incorporate corrections arising from the effective range of neutron-neutron scattering and evaluate their impact on the mean-square radii and electromagnetic response. In particular, we compute the ratio of the matter and charge radii, the shape of the dipole strength function, and the electric polarizability. Our results indicate that these corrections remain numerically small when the two-neutron separation energy of the Borromean nucleus is much less than 1 MeV.
