Determination of resonance energies and widths of the Mg 1P0 doubly excited states by the stabilization method with the B-spline-based configuration interaction approach

The resonance energies and widths of the Mg 3pns and 3pnd P-1(o) doubly excited states are determined by calculating the density of resonance states using the stabilization method with the B-spline-based configuration interaction (BSCI) approach. The effects due to the intrashell core excitation and intershell core-valence interactions are taken into account in the BSCI calculation by using a parametrized long-range core-polarization potential. Our results are in good agreement with the existing theoretical and experimental results.