I am astronomy professor, working at the Institut für Theoretische Physik und Astrophysik at Würzburg University. My research group is working on studies of black holes and the relativistic plasma jets being ejected from their immediate vicinity. Such jets are observed in both Galactic, stellar-mass black hole systems, and in extragalactic, supermassive black hole system and they dominate the emission of these objects over the whole spectrum from radio to gamma-ray energies. Such jets show fascinating phenomena like (apparent) superluminal motion, intraday variability, and dramatic outbursts. Curiously, this jet-production takes place only in a relatively small fraction of all black-hole systems: the radio-loud objects. How do black holes form jets? How are they collimated and accelerated? How do they interact with the environment of their host galaxies?

In collaboration with colleagues in Bamberg, at the Max-Planck-Institut für Radioastronomie in Bonn, and at institutes all over the world, we are trying to address these and other questions with the help of astronomical observations across the electromagnetic spectrum. We are particularly focusing on radio observations of jets using the special technique of Very Long Baseline Interferometry (VLBI) with the VLBA and the LBA, radio single-dish observations with the Effelsberg 100-m telescope, X-ray observations with XMM-Newton, Suzaku, Swift, and INTEGRAL, and gamma-ray observations with Fermi/LAT. I am a Fermi/LAT affiliated scientists and do a lot of my work in collaboration with the LAT Science Working Group (SWG) on Blazars and other AGN.

Major Projects and Collaborations that we are involved in include:

	MOJAVE - Monitoring Of Jets in Active galactic nuclei with VLBA Experiments
	TANAMI - Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry
	F-GAMMA - FERMI-GST AGN Multi-frequency Monitoring Alliance
	Fermi Science Working Group on Blazars and Other AGN (Image Credit: NASA E/PO, Sonoma State University, Aurore Simonnet)
	Swift Team
	ANTARES Collaboration
	KM3NeT Consortium

And here is a selection of the telescopes that we are using (click on the images for a full-resolution view):