ACCURATE CALCULATION OF SELF-ENERGY SCREENING DIAGRAMS FOR HIGH-Z-HELIUM-LIKE ATOMS

An accurate calculation of the self-energy screening diagrams for the ground state of high Z helium-like atoms is carried out. The total sel f-energy screening contribution is represented by the sum of the irred ucible, reducible and vertex parts. The irreducible contribution is ca lculated using the partial wave mass renormalization procedure. The re ducible and vertex contributions are grouped to be calculated without renormalization. It is found that the total self-energy screening cont ribution to the ground state energy of U90+ constitutes -9.2 eV. The t heoretical value of the ground state energy of U-238(90+) without high er order one-electron QED corrections is evaluated to be -261384(2) eV .