Two-channel Siegert pseudostate approach to a three-body Coulomb problem:S-wave resonances ofPs−(N=2,3)

Abstract

The recently developed two-channel Siegert pseudostate method of Sitnikov and Tolstikhin [Phys. Rev. A 67, 032714 (2003)] is here applied to the case of ${\mathrm{Ps}}^{\ensuremath{-}}$ ${(e}^{+}ee)$ exploiting the hyperspherical elliptic coordinates method. S-wave resonances and antiresonances are calculated and classified according to their locations in the complex plane of the uniformization parameter. The resonance positions and widths are compared to other accurate calculations.