A-dependence of ΔΔ-bond and charge symmetry energies

Abstract

The Δ -bond energies (ΔBΔΔ) of double-Δ hypernuclei provide a measure of the nature of the in-medium strength of the ΔΔ interaction. Likewise, the charge symmetry breaking in mirror nuclei with Δ and ΔΔ is expected to shed light on ΔN and ΔΔN interactions. A generalized mass formula, constructed earlier with broken SU(6) symmetry, is optimized and employed to calculate the separation energies from light to heavy nuclei. The new experimental data on ΔΔ-separation energy of a few double-Δ hypernuclei, and Δ-separation energy of several single-Δ hypernuclei have put more stringent constraint on this mass formula. The ΔBΔΔ values calculated with this optimized formula are in good agreement with the experimental data. This optimized mass formula can be used to predict ΔΔ-bond energy in neutron-rich environment, and to extract Coulomb-corrected symmetry energy from experimental data as well. It suggests existence of bound hypernuclei beyond the normal neutron-drip line.