Hypernuclear interactions and the binding energies of Λ and ΛΛ hypernuclei

By use of variational calculations a reasonable hadronic description is obtained of the s-shell hypernuclei, of 9/sub Λ/Be, and of the well depth, with ΛN forces which are consistent with Λp scattering and which are quite strongly spin-dependent, with reasonable TPE ΛNN forces and with strongly repulsive dispersive-type ΛNN forces. For the latter we also consider a spin-dependent version which is somewhat favored by our analysis. 9/sub Λ/Be is treated as a 2α+Λ system and is significantly overbound, ≅ MeV, if only αα and αΛ potentials are used. An ααΛ potential obtained from the ΛNN forces nicely accounts for this overbinding. The ΛΛ hypernuclei /sub Λ//sub Λ/6He and /sub Λ//sub Λ/10Be are treated as α+2Λ and 2α+2Λ systems. Use of the /sub Λ//sub Λ/10Be event gives ≅1.5 MeV too little binding for /sub Λ//sub Λ/6He. The 1S0 Λ/sub Λ/ potential obtained from 10/sub Λ//sub Λ/Be is quite strongly attractive, comparable to the ΛN and also to the NN potential without OPE