E. Angelakis, L. Fuhrmann, I. Nestoras, C. M. Fromm, R. Schmidt, J. A. Zensus, N. Marchili, T. P. Krichbaum, M. Perucho-Pla, H. Ungerechts, A. Sievers, D. Riquelme
The F-GAMMA program is a coordinated effort to investigate the physics of
Active Galactic Nuclei (AGNs) via multi-frequency monitoring of {\em Fermi}
blazars. The current study is concerned with the broad-band radio spectra
composed of measurement at ten frequencies between 2.64 and 142 GHz. It is
shown that any of the 78 sources studied can be classified in terms of their
variability characteristics in merely 5 types of variability. The first four
types are dominated by spectral evolution and can be reproduced by a simple
two-component system made of the quiescent spectrum of a large scale jet
populated with a flaring event evolving according to Marscher & Gear (1985).
The last type is characterized by an achromatic change of the broad-band
spectrum which must be attributed to a completely different mechanism. Here are
presented, the classification, the assumed physical system and the results of
simulations that have been conducted.
View original:
http://arxiv.org/abs/1111.6992
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