Triply excited 2P and 2D resonance of He-

The 2P (2s2s2p) and 2D (2s2p2p) resonance structure observed in the electron-helium scattering experiments has been investigated using a saddle-point technique. For 2P we obtain for the energy -0.796 93 a.u. with an 82-term wave function. This agrees well with the experimental result. In the past, the 2D structure was thought to be a Feshbach resonance. In this calculation, we show that the 2s2p 3P target is repulsive to the third p electron in the sense that the variational energy of the He- system is monotonically increased as the p electron approaches the target. Hence, the Feshbach resonance cannot be formed for this state. Some comments will be made concerning earlier theoretical calculations in the literature