Configuration space Faddeev calculations are performed for the binding energy
of Lambda-Lambda-6He and Lambda-9Be bound states, here considered as
alpha-Lambda-Lambda and alpha-alpha-Lambda clusters respectively, in order to
study the dependence of the calculated binding energy on the alpha-Lambda
potential input. For Lambda-Lambda-6He, using realistic interactions, the
uncertainty in extracting the Lambda-Lambda S=L=0 interaction strength does not
exceed 0.1 MeV, which is a fraction of the order of magnitude derived for other
theoretical uncertainties. For Lambda-9Be, the dependence of the calculated
binding energy on the alpha-Lambda potential is considerably larger, of order 1
MeV. Our results for Lambda-9Be suggest that the odd-state alpha-Lambda
interaction is substantially reduced with respect to the even-state component.Comment: 16 pages, including 4 figures, typos corrected, slightly revised,
accepted to Nuclear Physics