High-lying 1Po doubly-excited states of H- and He below the N = 3-13 hydrogenic thresholds

We present in this paper autoionizing energies of the 1Po states of H- and He belonging to the N = 3 - 13 hydrogenic thresholds. Calculations are performed for both inter-shell and intra-shell resonances using the screening constant by unit nuclear charge (SCUNC) method in the framework of a semi-empirical procedure. The results obtained in this paper agree very well with available theoretical and experimental values. These agreements point out the possibility to use the SCUNC method in the study of other Rydberg-type series in doubly excited states of He-positive like ions. (author)