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

We study doubly excited ${}^{1,3}{S}^e$, ${}^{1,3}{P}^o,$ and ${}^{1,3}{D}^e$ resonances in He below the $n=2\mathrm{}$ ${\mathrm{He}}^{+}$ threshold by the saddle-point complex-rotation method with $B$-spline functions. We calculated 78 resonances. Recently, accurate measurements on the ${}^1{P}^o$ have been performed, which allow detailed comparisons with our ab initio theoretical results. For ${}^1{P}^o$, we calculate six members in the ${}_2{\mathrm{}(0,1)\mathrm{}}_n^{+}(2\mathrm{}<~n<~7)$ series, five members in the ${}_2{\mathrm{}(1,0)\mathrm{}}_n^{-}(3\mathrm{}<~n<~7)$ series, and four members in the ${}_2\left(-{1,0)}_n^0\right(3\mathrm{}<~n<~6)$ series. The resonance energies and widths are compared with accurate experimental and theoretical results. The agreement is good. For other symmetries, the energies and widths are also calculated up to $n\cong$7, and are also in good agreement with available experimental and theoretical results.