8.4 GHz VLBI monitoring of the gamma-bright blazar PKS 0528+134

Citation
S. Britzen et al., 8.4 GHz VLBI monitoring of the gamma-bright blazar PKS 0528+134, ASTRON ASTR, 341(2), 1999, pp. 418-426
Citations number
70
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
00046361 → ACNP
Volume
341
Issue
2
Year of publication
1999
Pages
418 - 426
Database
ISI
SICI code
0004-6361(199901)341:2<418:8GVMOT>2.0.ZU;2-Q
Abstract
We present an analysis of the structural evolution of the jet of PKS 0528+1 34, one of the strongest gamma-active blazars. We study almost eight years (1986.25 - 1994.07) of jet evolution using 20 epochs taken from the extensi ve database of X-band geodetic VLBI observations. We discuss the activity a nd kinematics of the jet in the light of the prominence of this source in t he high energy regime. Rapid structural changes take place in its jet, and the VLBI image undergoes obvious structural evolution across the epochs in which the component motion follows different bent paths. The simplest model portrays PKS 0528+134 as a bent jet of length similar to 5 - 6 mas compris ing seven jet features. Not unexpectedly for a gamma-active quasar, we find superluminal motion of similar to 4 - 6c for five of the jet components. T hese five jet features can be traced over the entire observing period, whil e two newer components were ejected at times near epochs of enhanced gamma- ray activity. We can associate the increased activity in the radio and gamm a-ray bands with morphological changes in the source structure. We discuss the possible link between curvature of the jet and the brightness of the so urce at high energies.