Addendum: Doubly excited1,3Se,1,3Po, and1,3Deresonances in He below then=2He+threshold

Abstract

An extended variational method is used to study doubly excited ${}^{1}{D}^{e}$ ${\mathrm{H}}^{\ensuremath{-}}$ and ${}_{2}(\ensuremath{-}{1,0)}_{n}^{2}$ $(n=2,3)$ ${}^{1}{S}^{e};$ ${}_{2}{(0,1)}_{n}^{+}$ $(n=2,3),$ ${}_{2}{(1,0)}_{4}^{\ensuremath{-}}$, and ${}_{2}(\ensuremath{-}{1,0)}_{3}^{\ensuremath{-}}$ ${}^{1}{P}^{o}$; and ${}_{2}{(1,0)}_{n}^{+}$ $(n=2,3),$ ${}_{2}{(1,0)}_{4}^{+}$, and ${}_{2}{(0,1)}_{3}^{0}$ ${}^{1}{D}^{e}$ He, in which the electron-electron correlations are strong. Based on the flexibility of B-spline functions, we regrouped the saddle-point wave functions, obtained in the first saddle-point variational calculation, to fewer terms, and included more partial waves to achieve more accurate wave functions. More converged resonant energies and widths are obtained by the present saddle-point variational and complex-rotation method. The relation of convergence to electron-electron correlations is discussed. The present improved results are compared well with other theoretical results.