Isotope shift of the 1s2p 3P0-1s2s 1S0 level splitting in heavy He-like ions: Implications for atomic parity-nonconservation studies

Heavy He-like ions are considered to be promising candidates for atomic parity-nonconservation (PNC) studies, thanks to their relatively simple atomic structure and the significant mixing between the almost degenerate (for the atomic numbers Z∼64 and Z∼91) opposite-parity levels 1s2s 1S0 and 1s2p 3P0. A number of experiments exploiting this level mixing have been proposed, and their implementation requires a precise knowledge of the 2 3P0-2 1S0 energy splitting for different nuclear charges and isotopes. In this paper we performed a theoretical analysis of the level splitting, employing the relativistic many-body perturbation theory and including QED corrections for all isotopes in the intervals 54≤Z≤71 and 86≤Z≤93. Possible candidates for future experimental PNC studies are discussed.