Resonance states of Ps− using correlated wave functions Original Research Article

We have investigated the image resonance states of positronium negative ion below the image, 4 and 5 Ps thresholds using highly correlated exponential wave functions. Resonance parameters (positions and widths) are extracted employing both the stabilization method and the complex-coordinate rotation method. In addition to many Feshbach resonances below the various Ps thresholds, we have identified two image shape resonances with one each lying above the image and image thresholds, respectively. We have also identified three image shape resonances with one lying above the image threshold and two lying above image threshold. The image shape resonances associated with image Ps threshold and some other Feshbach resonances are reported for the first time in the literature.