New Faddeev-Yakubovsky calculations are reported for 6 ΛΛ He and 10 ΛΛ Be in terms of clusters of α's and Λ's, using ΛΛ s-wave potentials motivated by several of the Nijmegen model interactions. The self consistency of the ΛΛ hypernuclear world data for these species is discussed. The newly reported 6 ΛΛ He event is found to be compatible with ΛΛ interaction strengths provided by the Nijmegen soft-core one-boson-exchange model NSC97. Faddeev calculations for 5 ΛΛ H and 5 ΛΛ He suggest that these ΛΛ hypernuclei are stable against emitting Λ's for any (essentially attractive) ΛΛ interaction, whereas calcualtions for 4 ΛΛ H do not allow a clear-cut conclusion whether or not it is particle stable.

Evidence for particle stability of ( 4 )( LambdaLambda)H has been suggested by the BNL-AGS E906 experiment. We report on Faddeev-Yakubovsky calculations for the four-body LambdaLambdapn system using LambdaN interactions which reproduce the observed binding energy of (3)(Lambda)H(1 / 2(+)) within a Faddeev calculation for the Lambdapn subsystem. No ( 4 )( LambdaLambda)H bound state is found over a wide range of LambdaLambda interaction strengths, although the Faddeev equations for a three-body LambdaLambdad model of ( 4 )( LambdaLambda)H admit a 1(+) bound state for as weak a LambdaLambda interaction strength as required to reproduce B(LambdaLambda)(( 6 )( LambdaLambda)He).

New Faddeev-Yakubovsky calculations for light ΛΛ hypernuclei are presented in order to assess the self consistency of the ΛΛ-hypernuclear binding-energy world data and the implied strength of the ΛΛ interaction, in the wake of recent experimental reports on 4 ΛΛ H and 6 ΛΛ He. Using Gaussian softcore simulations of Nijmegen one-boson-exchange model interactions, the Nijmegen soft-core model NSC97 simulations are found close to reproducing the recently reported binding energy of 6 ΛΛ He, but not those of other species. For stranger systems, Faddeev calculations of light ΛΞ hypernuclei, using a simulation of the strongly attractive ΛΞ interactions due to the same model, suggest that 6 ΛΞ He marks the onset of nuclear stability for Ξ hyperons.

Faddeev calculations are reported for 5 ΛΛ H, 5 ΛΛ He and 6 ΛΛ He in terms of two Λ hyperons plus 3 H, 3 He, 4 He nuclear clusters respectively, using ΛΛ central potentials considered in past non-Faddeev calculations of 6 ΛΛ He. The convergence with respect to the partial-wave expansion is studied, and comparison is made with some of these ΛΛ hypernuclear calculations. The ΛΛ − ΞN mixing effect is briefly discussed.