Siegert pseudostate perturbation theory: one- and two-threshold cases

Koudai Toyota, Toru Morishita, Shinichi Watanabe

Perturbation theory for the Siegert pseudostates (SPS) [Phys.Rev.A 58, 2077 (1998) and Phys.Rev.A 67, 032714 (2003)] is studied for the case of two energetically separated threshol…