Analysis of the unbound spectrum of 12Li

摘要

The unbound nucleus ~(12)Li is evaluated by studying three-neutron one-proton excitations within the multistep shell model in the complex energy plane. It is found that the ground state of this system consists of an antibound 2- state. A number of narrow states at low energy are found which ensue from the coupling of resonances in ~(11)Li to continuum states close to threshold.