Multiepoch VLBI Observations of 4C 39.25: Superluminal Motion and Stationary Structure

DOI: 
10.1086/184839
Publication date: 
01/03/1987
Main author: 
Shaffer, David B.
IAA authors: 
Marcaide, Jon
Authors: 
Shaffer, David B.;Marscher, Alan P.;Marcaide, Jon;Romney, Jonathan D.
Journal: 
The Astrophysical Journal
Publication type: 
Article
Volume: 
314
Pages: 
L1-L5
Abstract: 
Eight VLBI maps of the quasar 4C 39.25 are presented, covering the time interval November 1979 to July 1985. During this period the compact components at the eastern and western ends of the source remained roughly stationary with respect to each other. A third component emerged from the western component in 1982 and proceeded to move (relative to the other two components) eastward at a rate of 0.16 + or - 0.02 marcsec per year. This corresponds to an average apparent speed between 3.2c and 8.4c for Hubble's constant between 100 and 50 km/s Mpc and q0 between 1 and 0. This superluminal motion contrasts with the stationary structure observed in the 1970s and also still observed between the eastern and western ends of the source. Possible explanations include superluminal feeding of a stationary compact counterpart to a classical radio lobe, an obstacle in a relativistic jet, a relativistic jet which alternatively expands and contracts owing to gradients in the confining pressure, and gravitational lensing of the compact radio emission.
Database: 
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/1987ApJ...314L...1S/abstract
ADS Bibcode: 
1987ApJ...314L...1S
Keywords: 
Astronomical Models;Quasars;Radio Jets (Astronomy);Relativistic Velocity;Very Long Base Interferometry;Data Correlation;Gravitational Lenses;Hubble Constant;Light Speed;Astrophysics;GALAXIES: JETS;INTERFEROMETRY;QUASARS