Positron scattering from hydrogen atom in quantum plasmas: S-wave resonance states

Abstract

The effects of quantum plasmas (QP) on the S-wave resonance states of the positron-hydrogen system have been investigated by using the stabilization method. An effective potential, in the form of exponential cosine screened Coulomb potential, is used to describe the interactions among the charged particles in QPs. A number of S-wave resonance states associated with different thresholds of s-states of hydrogen atom [H(ns)] and s-states of positronium atom [Ps(ns)] are reported. For plasma-free cases, our results agree well with the results of other reliable calculations. Moreover, an in-depth study has been made to investigate the changes produced in the energy Er and width Γ of those states due to varying screening strength of QP. Our present results of energy and width of the positron-hydrogen system under QP associated with the higher-lying thresholds of hydrogen (H) and positronium (Ps) are reported for the first time in the literature.