Cluster models of _ΛΛ⁶He and _Lambda;⁹Be hypernuclei

Configuration space Faddeev calculations are performed for the binding energy of _ΛΛ⁶He and _Λ⁹Be bound states, here considered as αΛΛ and ααΛ clusters respectively, in order to study the dependence of the calculated binding energy on the αΛ potential input. For _ΛΛ⁶He, using realistic interactions, the uncertainty in extracting the ΛΛ ¹S₀ interaction strength does not exceed 0.1 MeV, which is a fraction of the order of magnitude derived for other theoretical uncertainties. For _Λ⁹Be, the dependence of the calculated binding energy on the αΛ potential is considerably larger, of order 1 MeV. Our results for _Λ⁹Be suggest that the odd-state αΛ interaction is substantially reduced with respect to the even-state component.