X-ray spectroscopy of Be- to He-like germanium

We report on the introduction of Ge(CH3)4 into the Dresden EBIS, a further development of the Dresden EBIT. Energy-dispersive X-ray spectra from highly charged germanium ions are measured with a Si(Li)-detector at different source operation conditions, such as electron currents ranging from 50 mA to 200 mA at electron energies of up to 20 keV. Direct excitation processes in Ge30+ at 18 keV electron energy have been analyzed as well as radiative electron capture into Ge28+ up to Ge31+ ions. Furthermore satellite lines from dielectronic recombination processes in Ge28+ to Ge30+ ions have been measured.