1. Spectroscopy/ImagingLeibniz Institute of Photonic Technology Albert-Einstein-Str. 9 D-07745 Jena Germany
2. Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University Helmholtzweg 4 D-07745 Jena Germany
3. PlasmadiagnosticsLeibniz Institute for Plasma Science and Technology Felix-Hausdorff-Str. 2 D-17489 Greifswald Germany