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Date and Time of the Query: 2019-06-17 T07:16:07 PDT
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For refcode 1993ApJ...407...65G:
Retrieve 106 NED objects in this reference.
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1993ApJ...407...65G RELATIVISTIC BULK MOTION IN ACTIVE GALACTIC NUCLEI G. GHISELLINI, P. PADOVANI, A. CELOTTI, AND L. MARASCHI Received 1992 July 1; accepted 1992 September 29 ABSTRACT We discuss the evidence for relativistic bulk motion of the emitting plasma in the nuclei of ~100 radio sources, which include BL Lacertae objects, radio quasars, and radio galaxies, with published VBLI measurements of the core angular dimension and radio flux. Comparing the predicted and observed high-frequency (X-ray) flux, in the framework of the synchrotron self-Compton model, we derive the beaming or Doppler factor for all sources. This is compared with other beaming indicators, such as the value of the expansion velocity (mostly superluminal and available for ~40% of the objects) and the ratio of the core to the extended radio flux (available for all but two sources). We find that the different beaming indicators agree reasonably well, supporting the simple kinematic model of ballistic motion of knots in a jet. Furthermore, the mean values of the bulk Lorentz factor and the angle to the line of sight derived for the superluminal sources are consistent with those found from the attempts to unify BL Lacertae objects and radio-loud quasars with Fanaroff-Riley Types I and II radio galaxies, respectively. Subject headings: galaxies: active - galaxies: kinematics and dynamics - galaxies: nuclei - radiation mechanisms: miscellaneous - relativity
Retrieve 106 NED objects in this reference.
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