The singlet S-wave resonances of He atom in dense quantum plasmas

The singlet S-wave resonances of the He atom embedded in dense quantum plasmas are investigated by applying the complex-coordinate rotation method. The modified Debye-H & uuml;ckel potential is used to model the effective interactions of the test atom in a dense quantum plasma environment. The explicitly correlated Hylleraas configuration-interaction basis function is employed to take into account the electron correlation effect. The first ten S-wave resonance states of the He atom below the N = 2 thresholds of the He+ ion are calculated, and the resonance energies and widths at a variety of screening parameters are obtained with high accuracy. The plasma screening effect on the expectation values of the radial and angular physical quantities are analyzed for the first time. (c) 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).