521 citations · 10.3k across the 138 of their papers we have counts for
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Adiabatic expansion and magnetic fields in AGN jets
A. B. Pushkarev, Y. Y. Kovalev, A. P. Lobanov
Results of high-resolution simultaneous multi-frequency 8.1-15.4 GHz VLBA polarimetric observations of relativistic jets in active galactic nuclei (the MOJAVE-2 project) are analyz…
Probing parsec scale jets in AGN with geodetic VLBI
A. B. Pushkarev, Y. Y. Kovalev
We report on an ongoing effort to image active galactic nuclei simultaneously observed at 2.3 and 8.6 GHz in the framework of a long-term VLBI project RDV (Research and Development…
15 GHz VLBI detection of the HST-1 feature in the M87 jet
C. S. Chang, E. Ros, Y. Y. Kovalev +1
A bright feature 100 pc away from the core in the powerful jet of M 87 shows mysterious properties. Earlier radio, optical and X-ray observations have shown that this feature, labe…
High-resolution studies of the twin jet in NGC 1052
E. Ros, M. Kadler, Y. Y. Kovalev +3
The radio loud galaxy NGC 1052 is being studied in an intensive multi-band campaign including X-ray brigthness monitoring and spectroscopic observations, single-dish radio brightne…
Physics of the central region in the quasar 0850+581
Y. Y. Kovalev, A. P. Lobanov, A. B. Pushkarev
The apparent position of the origin (core) of extragalactic radio jets shifts with the observing frequency, owing to synchrotron self-absorption and external absorption. One of the…
Testing adiabatic expansion of shocks in parsec-scale jets by dual-frequency VLBI experiments
A. B. Pushkarev, Y. Y. Kovalev, A. P. Lobanov
We present results of simultaneous dual-frequency (2 GHz and 8 GHz) very long baseline interferometry (VLBI) observations of 12 active galactic nuclei with prominent jets. Spectral…
Kinematics of AGN and Quasar Jets
K. I. Kellermann, M. L. Lister, D. C. Homan +3
The major multi-epoch VLBA programs are described and discussed in terms of relativistic beaming models. Broadly speaking the observed kinematics are consistent with models having…
Opacity in compact extragalactic radio sources and its effect on astrophysical and astrometric studies
Y. Y. Kovalev, A. P. Lobanov, A. B. Pushkarev +1
The apparent position of the "core" in a parsec-scale radio jet (a compact, bright emitting region at the narrow end of the jet) depends on the observing frequency, owing to synchr…
The Trails of Superluminal Jet Components in 3C111
M. Kadler, E. Ros, M. Perucho +8
In 1996, a major radio flux-density outburst occured in the broad-line radio galaxy 3C111. It was followed by a particularly bright plasma ejection associated with a superluminal j…
Opacity in compact extragalactic radio sources and its effect on radio-optical reference frame alignment
Y. Y. Kovalev, A. P. Lobanov, A. B. Pushkarev +1
Accurate alignment of the radio and optical celestial reference frames requires detailed understanding of physical factors that may cause offsets between the positions of the same…
Multiwavelength Observations of the Powerful Gamma-ray Quasar PKS 1510-089: Clues on the Jet Composition
J. Kataoka, G. Madejski, M. Sikora +16
We present the results from a multiwavelength campaign of the powerful Gamma-ray quasar PKS 1510-089. This campaign commenced with a deep Suzaku observation lasting three days for…
Intrinsic Structure and Kinematics of the Sub-Parsec Scale Jet of M87
Y. Y. Kovalev
We report new results from a sub-parsec scale study of the inner jet in M87 performed at 15 GHz with the Very Long Baseline Array. We have detected a limb brightened structure of t…
The Inner Jet of the Radio Galaxy M87
Y. Y. Kovalev, M. L. Lister, D. C. Homan +1
We report new 2 cm VLBA images of the inner radio jet of M87 showing a limb brightened structure and unambiguous evidence for a faint 3 mas long counter-feature which also appears…
The WEBT Campaign on the Blazar 3C279 in 2006
M. Boettcher
The quasar 3C279 was the target of an extensive multiwavelength monitoring campaign from January through April 2006, including an optical-IR-radio monitoring campaign by the Whole…
Relativistic Beaming and the Intrinsic Properties of Extragalactic Radio Jets
M. H. Cohen, M. L. Lister, D. C. Homan +4
Relations between the observed quantities for a beamed radio jet, apparent transverse speed and apparent luminosity (beta_app,L), and the intrinsic quantities, Lorentz factor and i…
The innermost regions of Active Galactic Nuclei - from radio to X-rays
Eduardo Ros, Matthias Kadler, Sarah Kaufmann +3
Active Galactic Nuclei (AGN) can be probed by at different regions of the electromagnetic spectrum: e.g., radio observations reveal the nature of their relativistic jets and their…
Multifrequency variability of the blazar AO 0235+164. The WEBT campaign in 2004-2005 and long-term SED analysis
C. M. Raiteri, M. Villata, M. Kadler +3
A huge multiwavelength campaign targeting the blazar AO 0235+164 was organized by the Whole Earth Blazar Telescope (WEBT) in 2003-2005 to study the variability properties of the so…
Multiwavelength Observations of 3C 66A during the WEBT campaign of 2003 - 2004
M. Boettcher, J. Harvey, M. Joshi
The BL Lac object 3C 66A was the target of an extensive multiwavelength monitoring campaign from July 2003 through April 2004, involving observations throughout the electromagnetic…
Sub-milliarcsecond Imaging of Quasars and Active Galactic Nuclei. IV. Fine Scale Structure
Y. Y. Kovalev, K. I. Kellermann, M. L. Lister +11
We have used VLBA fringe visibility data obtained at 15 GHz to examine the compact structure in 250 extragalactic radio sources. For 171 sources in our sample, more than half of th…
The WEBT campaign to observe AO 0235+16 in the 2003-2004 observing season
C. M. Raiteri, M. Villata, M. A. Ibrahimov +2
A multiwavelength campaign on the BL Lac object AO 0235+16 has been organized by the WEBT collaboration during the observing seasons 2003-2004 and 2004-2005. Here we report on the…
Combined VLBI- and X-ray Observations of Active Galactic Nuclei
M. Kadler, E. Ros, J. Kerp +2
Compact radio cores in radio-loud active galactic nuclei (AGNs) are classical targets of Very-Long-Baseline interferometric (VLBI) research. Until today little has been known about…