Jet Activity in Supermassive Binary Black Holes

Supermassive binary black holes (SBBHs) are a natural outcome of galaxy mergers. Here we show that low-frequency (f ≤ 10-6 Hz) quasi-periodic variability observed from radioloud, jet-emitting AGNs provides substantial inductive support for the presence of close (d ≤ 0.1 pc) SBBHs in their centers. We estimate the properties for a sample of SBBH candidates and discuss the results within the context of jet activity and binary evolution.