Structure of halo nuclei 14Be and 32Ne

The density-dependent relativistic mean-field theory, without introducing any adjustment, is applied to the nuclei 12Be, 14Be, 30Ne.and 32Ne. Contrary to the failure of the relativistic mean-field theory for the halo nuclei 14Be and 32Ne, the density-dependent relativistic mean-field theory, in which the relativistic Brueckner-Hartree-Fock results of nuclear matter have been incorporated, can satisfactorily reproduce the experimental data of the binding energy and the abnormally large root-mean-square radius. It is also predicted that the halo neutrons in 14Be occupy the 2s12 level instead of the 1d52 level and the halo neutrons in 32Ne occupy the 2p32 and 2p12 levels instead of the 1f72. A new picture on the appearance of the neutron halo has been obtained.