Study of the 18Ne and 11Li Nuclei in a Three-body Model

We investigate the structure of the nuclei Ne-18 and Li-11 within a three-body model using Faddeev equations with the hyperspherical adiabatic expansion method. The Ne-18 system is described as an inert 160 core and two protons. Besides reproducing the experimentally known bound states, two tentative states with J(pi)=3(+) and 1(-) are predicted close to the two-proton separation threshold. We also find several low-lying resonances based on a 3(-) excited state of the core. The Li-11 nucleus is treated using a Li-9+n+n model. In this case, the lack of information of the Li-9+n spectrum only allows us to obtain the ground state with enough accuracy. The calculated three-body wavefunction has been used to develop a simplified two-body model of the Li-11 nucleus (dineutron model). This model is found to reproduce very well the recent data for the electric transition probability, B(E1).