Unification and physical interpretation of the radio spectra variability   patterns in Fermi blazars and jet emission from NLSy1s
  The F-GAMMA program is among the most comprehensive programs that aim at understanding the physics in active galactic nuclei through the multi-frequency monitoring of Fermi blazars. Here we discuss monthly sampled broad-band radio spectra (2.6 - 142 GHz). Two different studies are presented. (a) We discuss that the variability patterns traced can be classified into two classes: (1) to those showing intense spectral-evolution and (2) those showing a self-similar quasi-achromatic behaviour. We show that a simple two-component model can very well reproduce the observed phenomenologies. (b) We present the cm-to-mm behaviour of three gamma-ray bright Narrow Line Seyfert 1 galaxies over time spans varying between ~1.5 and 3 years and compare their variability characteristics with typical blazars. 
E. Angelakis, L. Fuhrmann, I. Nestoras, C. M. Fromm, R. Schmidt, J. A.   Zensus, N. Marchili, T. P. Krichbaum, M. Perucho, H...
astro-ph.HE