Ab Initio Study of the Beryllium Isotopes Be7 to Be12

Abstract

We present a systematic study of the low-lying states in beryllium isotopes from Be7 to Be12 using nuclear lattice effective field theory with the N3LO interaction. Our calculations achieve good agreement with experimental data for energies, radii, and electromagnetic properties. We introduce a novel, model-independent method to quantify nuclear shapes, uncovering a distinct pattern in the interplay between positive and negative parity states across the isotopic chain. By combining Monte Carlo sampling of the many-body density operator with a novel nucleon-grouping algorithm, the prominent two-center cluster structures, the emergence of one-neutron halo, complex nuclear molecular dynamics such as π orbital and σ orbital, emerge naturally. Published by the American Physical Society 2025