A model of closed shell plus two particle nuclei

Previously a very simple model for calculating two-nucleon correlations outside of an inert core has been suggested. This model gave the possibility to investigate the surface clusterization of nucleons outside a closed shell. It is interesting that a certain clusterization takes place, even for the weakest interaction between the particles (which could not lead to a bound state in the absence of the core). But the model had one deficiency - it was implicitly assumed that the main contribution to the wave function of this three-body system comes from the one-nucleon s-states (l=0). This may be not so bad in the O17 case, where (without spin-orbit splitting) the 2s-state lies lower than the 1d-state, but, in general this assumption cannot be upheld. The authors reconstruct the model to make it more realistic, but at the same time very simple. (Auth.)