2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/192250The two--neutron separation energy of $^6$He has been reproduced for the first time in a realistic parameter--free microscopic multicluster model comprising the $α+n+n$ and $t+t$ clusterizations, with $α$ cluster breathing excitations included. The contribution of the $t+t$ channel is substantial. A very thick (0.85 fm) neutron halo has been found in full agreement with the results of the latest phenomenological analysis.Submitted to Phys. Rev. C, 8 pages, Latex with Revtex, 2 figures (not included) available on request, 08-03-93Nuclear Theorytext