EBITs are versatile tools for spectroscopic studies of partially ionized atomic systems, mainly in the x-ray domain. This yields valuable information for fundamental atomic physics as well as astrophysics. Ion charge state distributions, resulting from ionization and recombination processes, can be observed and used to benchmark plasma dynamics. Furthermore, EBITs can be used as small stand-alone ion sources, as they are already used for example at the HITRAP facility. The Jena S-EBIT facility are two EBITs, the former R- and S-EBIT from Stockholm*, which both are suitable for x-ray spectroscopy studies and ion extraction. The S-EBIT I has been used as a tool for x-ray spectroscopy, including the testing of newly developed x-ray detectors, like the magnetic metallic microcalorimeter maXs30**. In addition, the setup was expanded by a testing beamline, to evaluate the potential of the S-EBIT I as an ion source. The S-EBIT II is currently in commissioning for operation as a standalone ion source for HITRAP in the near future. This will provide new opportunities for local experiments, like the ARTEMIS experiment, independently from the GSI accelerator infrastructure.

Resonant photo-excitation provides a direct tool for investigating electronic transitions in atoms and ions. By combining EBITs and ultrabrilliant x-ray sources this kind of spectroscopy became also available for highly charged ions. Here we present the PolarX-EBIT, a compact permanent magnet EBIT* built by the Max-Planck-Institute for Nuclear Physics and University Jena specifically for operation at synchrotron radiation light source facilities. It employs a novel off-axis electron gun, allowing the photon beam to pass through the trap and be made available for downstream setups. Additionally, it features fast-switching power supplies for charge breeding and background reduction schemes, a time-of-flight ion extraction beamline and large area SDD detectors. Multiple successful experiments have been performed in the soft and hard x-ray regimes at the light sources BESSY II and PETRA III, measuring transition energies, oscillator strengths, natural line widths, photoionization and population balance**. Furthermore, narrow lines of He-like ions have also been used as a diagnostic tool for the spectral performance of the photon beamlines.