Hiroshi Nagai, Monica Orienti, Motoki Kino, Kenta Suzuki, Gabriele Giovannini, Akihiro Doi, Keiichi Asada, Marcello Giroletti, Jun Kataoka, Filippo D'Ammando, Makoto Inoue, Anne Lahteenmaki, Merja Tornikoski, Jonathan Leon-Tavares, Seiji Kameno, Uwe Bach
The radio galaxy 3C 84 is a representative of gamma-ray-bright misaligned active galactic nuclei (AGNs) and one of the best laboratories to study the radio properties of the sub-pc jet in connection with the gamma-ray emission. In order to identify possible radio counterparts of the gamma-ray emissions in 3C 84, we study the change in structure within the central 1 pc and the light curve of sub-pc-size components C1, C2, and C3. We search for any correlation between changes in the radio components and the gamma-ray flares by making use of VLBI and single dish data. Throughout the radio monitoring spanning over two GeV gamma-ray flares detected by the {\it Fermi}-LAT and the MAGIC Cherenkov Telescope in the periods of 2009 April to May and 2010 June to August, total flux density in radio band increases on average. This flux increase mostly originates in C3. Although the gamma-ray flares span on the timescale of days to weeks, no clear correlation with the radio light curve on this timescale is found. Any new prominent components and change in morphology associated with the gamma-ray flares are not found on the VLBI images.
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http://arxiv.org/abs/1204.1392
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