Comparison between the Gamow shell model and the cluster-orbital shell model for weakly bound systems

Abstract

We study contributions of poles and continua of the single-particle states to the wave function obtained by the cluster-orbital shell model (COSM). The COSM wave function is described in terms of a linear combination of nonorthogonal Gaussian basis sets. We study oxygen and helium isotopes as examples of normal and weakly bound nuclei. In the investigation of the contribution of the single-particle states, we expand the COSM wave function by using an extended completeness relation, which is constructed by the solution of the single-particle Hamiltonian. We use the complex scaling method to obtain the bound, resonant, and continuum states of the Hamiltonian and construct the extended completeness relation. The results are compared with those obtained by the Gamow shell model calculation.