Relatore
Descrizione
The broad-line radio galaxy 3C 120 has the properties of a Seyfert galaxy at optical through X-ray frequencies, and a quasar-like blazar at radio frequencies. It is one of a very small number - and probably the best - of active galaxies suitable for probing the relationship between the accretion disk/corona and a relativistic jet. We recently monitored 3C 120 with Swift at optical/UV/X-ray frequencies alongside our long-standing VLBA monthly imaging program and monitoring of the 37 GHz flux at the Metsahovi Radio Observatory. The changing optical-UV spectrum reveals the presence of a component with an inverted spectrum, which may be synchrotron radiation from electrons with a nearly mono-energetic (roughly 10 GeV) distribution. A flare from
optical to X-ray frequencies appears to have originated near the radio core 0.5-1.3 pc from the black hole. Analysis of the optical-X-ray light curves disfavors the proposal that the inner accretion disk is disrupted prior to the launch of a superluminal knot seen in the VLBA images.
This research was supported in part by NASA through the Swift and Fermi guest investigator programs, grants NNX16AN69G and 80NSSC17K0649, and by the National Science Foundation via grant AST-1615796.
