Probing the resonance of Dirac particle in the relativistic point-coupling model by complex-momentum-representation method

Abstract

The complex-momentum-representation (CMR) method is applied to investigate the single-particle resonant states in the relativistic point-coupling model. Taking Sn isotopes as examples, the resonant energies and widths are systematically calculated and compared with those from the Green’s function method. It is found that the resonant states are predicted accurately with the CMR method even for those lying near the continuum threshold. The predicted resonant energies and widths generally decrease with the increase of neutron number, which are mainly induced by the different potentials of Sn isotopes. It is also found that the wave functions in the momentum space are relatively localized for the resonant states especially for the broad resonances, while they have long tails in the coordinate space, which indicates the advantage of CMR method in studying the properties of resonant states.