Ia. Goidenko et al., Radiative corrections in highly charged ions and tests of QED in strong electric and magnetic fields, PHYS SCR, T92, 2001, pp. 426-428
To provide predictions of the Lamb shift of highly charged ions on the leve
l of accuracy of about 10(-6) has been achieved after exact results for the
contributions of all two-photon self-energy diagrams have been performed.
We report on the present status of our Lamb-shift calculations including al
l QED-corrections of first- and second-order in the finestructure constant
a and all relevant nuclear effects. An excellent agreement between the most
recent experimental data for Lamb shift of the ls-ground state in hydrogen
like uranium can be stated. This can serve as a sensitive test of QED in th
e strongest electric fields accessible in nature. In a second part of this
article we report about an all-order numerical evaluation of the one-photon
selfenergy at low nuclear charge (Z = 1,...,5). A sensitive comparison of
our numerical approach with analytical approach to the one-photon selfenerg
y confirms the consistency of these two different approaches (numerical and
analytic) to very high precision.