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VLBI Observations of a Complete Sample of Radio Galaxies. IV-The Radio Galaxies NGC2484, 3C109 and 3C382

G. Giovannini·L. Feretti·T. Venturi·L. Lara·J. Marcaide·M. Rioja·S. R. Spangler·A. E. Wehrle
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Abstract

We present here new VLBI observations of one FR-I radio galaxy (NGC2484) and two Broad Line FR-II radio galaxies (3C109 and 3C382). For 3C109 new VLA maps are also shown. These sources belong to a complete sample of radio galaxies under study for a better knowledge of their structures at parsec resolution. The parsec structure of these 3 objects is very similar: asymmetric emission which we interpret as the core plus a one-sided jet. The parsec scale jet is always on the same side of the main kpc-scale jet. The limit on the jet to counterjet brightness ratio, the ratio of the core radio power to the total radio power and the Synchrotron-self Compton model allow us to derive some constraints on the jet velocity and orientation with respect to the line of sight. From these data and from those published on 2 other sources of our sample, we suggest that parsec scale jets are relativistic in both FR-I and FR-II radio galaxies and that pc scale properties in FR-I and FR-II radio galaxies are very similar despite of the large difference between these two classes of radio galaxies on the kpc scale.

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G. Giovannini, L. Feretti, T. Venturi, L. Lara, J. Marcaide, M. Rioja, S. R. Spangler, A. E. Wehrle. 1994-06-13. VLBI Observations of a Complete Sample of Radio Galaxies. IV-The Radio Galaxies NGC2484, 3C109 and 3C382. https://doi.org/10.1086/174799

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