A Multiband Approach to AGN: Radioscopy & Radio Astronomy
  Only in the radio-loud population of active galactic nuclei (AGN) does the production, collimation, and acceleration of powerful relativistic jets take place. We introduce here a concept of combined VLBI- and X-ray spectroscopic observations of sources with relativistic, broad iron lines. This approach has enormous potential to yield deep insights into the accretion/jet-production process in AGN. Better knowledge of the milliarcsecond-resolution radio structure of the nuclear radio cores in so-called ``radio-quiet'' broad-iron-line Seyfert galaxies is essential for future combined radio/X-ray studies of the different modes of radio-jet production in accreting black hole systems. 
M. Kadler (MPIfR), E. Ros (MPIfR), J. Kerp (RAIUB), A.L. Roy (MPIfR),   A.P. Marscher (Inst. f. Astroph. Research, BU), J.A....