SMI Seminar on fundamental interactions and symmetries

X-ray spectroscopy of highly charged ions with synchrotron light sources

by Dr René Steinbrügge (Heidelberger Ionenstrahl-Therapiezentrum, Universitätsklinikum Heidelberg)


For online participation via zoom please request the link the latest by 12:00 on the day of the seminar via email to martin dot simon at oeaw dot ac dot at


The properties of electronic transitions in highly charged ions are important for modelling hot plasmas, testing quantum electrodynamic calculations and applications in metrology. By combining an electron beam ion trap (EBIT) with monochromatized x-rays from synchrotron radiation sources, these transitions can be resonantly excited, providing a direct way of investigating them.

I will present measurements using the compact PolarX-EBIT, which was designed specifically for the use at synchrotron light sources. In multiple campaigns, we measured transition energies, oscillator strengths, natural line widths, photoionization and population balance of iron, oxygen, and neon ions in several charge states, providing data needed for astrophysical models. The achieved precision allows to test quantum electrodynamics calculations of few electron systems. As transitions in highly charged ions are less sensitive to external perturbations, they can also serve as energy references for other experiments. Furthermore, the narrow lines of He-like ions have been used as a diagnostic tool for the spectral performance of the photon beamlines.