Narrow Near-Threshold Resonance in e⁺–He⁺ Scattering

An independent alternative calculation is performed for narrow near-threshold resonances in the e⁺–He⁺ system using the stabilization method in the framework of hyperspherical coordinates (HSSM). A narrow resonance at E_r=−0.249995 with width Γ=1.9×10⁻⁵, associated with the He²⁺–Ps (n =1) threshold is confirmed. The resonances around the energies −0.365 and −0.195, predicted by Bhatia and Drachman Phys. Rev. A 42 (1990) 5117 and confirmed by Ho Phys. Rev. A 53 (1996) 3165, do not appear in our calculations.