Canonical states in relativistic continuum theory with the Green's function method: Neutrons in continuum of zirconium giant-halo nuclei

Abstract

The canonical states in the relativistic continuum Hartree-Bogoliubov theory with Green's function method are obtained by diagonalizing the density matrix on a spatial mesh. Taking the giant halo nucleus $^{128}\mathrm{Zr}$ as an example, the obtained canonical single-particle energies and wave functions are compared in detail with the corresponding calculations with the box-discretized method. The occupation number ${v}_{i}^{2}$ in the canonical basis and the neutrons in continuum ${N}_{c}$ are investigated for the Zr giant halo nuclei. The dependencies on the pairing strength ${V}_{0}$ and on the different density functionals PK1 and NL-SH are also studied. It is found that the calculations with Green's function and box-discretized methods are almost consistent in describing nuclear global properties and the neutrons in continuum, meanwhile the ${N}_{c}$ of giant halo nuclei may heavily depend on the adopted pairing strength as well as the density functional.