Per Sunnergren

Regularization Corrections to the Partial-Wave Renormalization Procedure*

Abstract A description of the partial-wave renormalization (PWR), used for calculating the first-order self energy and certain higher-order effects for the energy levels in highly charged ions, is presented. We put special emphasis on correction terms which have to be considered due to the use of the non-covariant subtraction scheme used in PWR.

A theoretical survey of QED tests in highly charged ions

Recent progress in precision tests of QED in strong nuclear fields is presented and discussed. The discussion is focused on theoretical comparisons with experiment on the 1s Lamb-shift in H-like uranium, the two-electron Lamb-shift in He-like ions, the hyperfine structure of H-like bismuth and the bound-electron g-factor in H-like ions.

Adapting high Z methods for a \({\user1{g}_\user1{J} } \) factor prediction for C5+, S15+ and Ca19+

AbstractWe present a

The gJ Factor of an Electron Bound in Hydrogen-Like Carbon: Status of the Theoretical Predictions

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gj factor of an electron bound in a hydrogenlike ion

factor prediction for the ground state of C5+, S15+ and Ca19+. For this purpose we have developed a subtraction scheme within the QED calculations which is outlined in this contribution. Current theoretical limits are mentioned.

Two-electron Lamb-shift calculations on heliumlike ions.

The procedure for calculating combined relativistic many-body-QED effects for heavy, highly charged ions is reviewed. Numerical results are presented for some helium- and lithium-like ions and compared with experiments.

Accurate vacuum-polarization calculations

We present the known theoretical contributions to the gJ factor of an electron bound in hydrogen like carbon. In particular we outline the calculation scheme for the quantum electrodynamical (QED) corrections of order (απ) and present their current theoretical uncertainties. The known terms of the (Zα) expansion are found to be insufficient to describe the current experimental data.

RADIATIVE CORRECTIONS TO THE ELECTRON G-FACTOR IN H-LIKE IONS

By means of new experimental techniques heavy ions with a few electrons can now be studied with improved accuracy. In combination with new computational schemes such data can be used for testing QED at strong fields. In this paper we discuss in particular recent QED calculations on lithium-like uranium and on some helium-like ions and compare them with corresponding experimental results. The agreement between theory and experiments is generally very good. The helium-like ions are of particular interest in this respect. Here, it is possible to determine the two-electron QED contribution independently of the much larger one-electron part. Only a moderate improvement in the experimental accuracy is needed in order to make it possible, for the first time, to test QED effects at strong fields beyond the lowest-order Lamb shift.