Inner-shell electrons naturally sense the electric field close to the nucleus, which can reach
extreme values beyond 1015 V cm− 1 for the innermost electrons. Especially in few-electron …

When collecting spectroscopic data on at least four isotopes, nonlinearities in the King plot
are a possible sign of physics beyond the standard model. In this work, an improved …

The nuclear-polarization corrections to the energy levels of highly charged ions are
systematically investigated to leading order in the fine-structure constant. To this end, the …

A critical set of two-loop quantum electrodynamics corrections to the g factor of hydrogenlike
ions is calculated in the Furry picture. These corrections are due to the polarization of the …

The finite nuclear size corrections to the ground state energies and g-factors in muonic
atoms are investigated for several elements. Both approximative and exact solutions of the …

The influence of hypothetical new interactions beyond the standard model on atomic spectra
has attracted recent interest. In the present work, interelectronic photon-exchange …

Highly accurate algebraic relations between the fine structure constant a and a wide range
of particle masses are given, ranging from Δa/a=(2.1±0.1)× 10-7 to Δa/a=(-2.7±0.3±0.6)× 10 …

Penning trap experiments for fundamental atomic physics Page 1 Habilitationsschrift zur
Erlangung der Venia legendi für das Fach Physik der Ruprecht-Karls-Universität Heidelberg …

The current status of the theoretical investigation of the bound-electron g factor in lithium-like
and boron-like highly charged ions is reported. Some tension between the several …