He-6(Lambda Lambda) and Be-9(Lambda) systems in the three-body cluster model treated on the basis of differential Faddeev equations

The He-6(Lambda Lambda) and Be-9(Lambda) hypernuclei are treated as the S = 0, T = 0 (for the former) and S = 1/2, T = 0 (for the latter) bound stales of the three-cluster systems Lambda Lambda alpha and Lambda alpha alpha, respectively. The cluster-reduction method is used to solve the s-wave differential Faddeev equations for these systems. On the basis of the MT I-III model, the Lambda Lambda interaction potential is specified in the form V-Lambda Lambda = 2/3 V-NN. Phenomenological potentials are used to describe Lambda alpha and alpha alpha interactions. The binding energies of the He-6(Lambda Lambda) and Be-9(Lambda) hypernuclei and the parameters of low-energy Lambda-hyperon and alpha-particle scattering on a He-5(Lambda) hypernucleus are calculated. It is shown that the proposed Lambda Lambda interaction potential makes it possible to reproduce faithfully the binding energy of the He-6(Lambda Lambda) hypernucleus and that scattering in the Lambda(Lambda)(5)He system is similar to neutron scattering on a deuteron. (C) 2000 MAIK Nauka/Interperiodica.