English
Related papers

Related papers: A study of bent jets in active galactic nuclei at …

200 papers

Observations made with the VLBA have led to fundamental advances in our understanding of how radio jets in AGN evolve from parsec-scales out to distances exceeding several hundred kiloparsecs. In this review I discuss current models of…

Astrophysics · Physics 2007-07-12 Matthew L. Lister

Broadband emission from relativistic outflows (jets) of active galactic nuclei (AGN) and gamma-ray bursts (GRBs) contains valuable information about the nature of the jet itself, and about the central engine which launches it. Using special…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Petar Mimica , Miguel Angel Aloy , Jesus M. Rueda-Becerril , Siham Tabik , Carmen Aloy

TANAMI is a multiwavelength program monitoring active galactic nuclei (AGN) south of -30deg declination including high-resolution Very Long Baseline Interferometry (VLBI) imaging, radio, optical/UV, X-ray and gamma-ray studies. We have…

Active Galactic Nuclei (AGNs) observed with the technique of very long baseline interferometry (VLBI) are used as fiducial references on the sky to precisely measure the shape and orientation of the Earth. Their positions form a celestial…

Astrophysics of Galaxies · Physics 2025-01-31 Ming Hui Xu , Patrick Charlot

We report that active galactic nucleus (AGN) jets are causally connected on parsec scales, based on 15 GHz Very Long Baseline Array (VLBA) data from a sample of 133 AGN jets. This result is achieved through a new method for measuring the…

High Energy Astrophysical Phenomena · Physics 2014-01-28 E. Clausen-Brown , T. Savolainen , A. B. Pushkarev , Y. Y. Kovalev , J. A. Zensus

We aim to investigate the relationship between radio jet activity on parsec-scales and the characteristics of both the bright active galactic nuclei (AGN) and their broad line regions (BLR). For this purpose, we combine 2cm Very Long…

Astrophysics · Physics 2017-08-23 T. G. Arshakian , V. H. Chavushyan , E. Ros , J. A. Zensus

Using stacking of images obtained at different epochs, we studied the variability properties of linear polarization of active galactic nucleus (AGN) jets on parsec-scales. Our sample is drawn from the MOJAVE programme, and consists of 436…

High Energy Astrophysical Phenomena · Physics 2023-06-16 D. I. Zobnina , H. D. Aller , M. F. Aller , D. C. Homan , Y. Y. Kovalev , M. L. Lister , I. N. Pashchenko , A. B. Pushkarev , T. Savolainen

An increasing number of observations and simulations suggests that low-power (<10$^{44}$ erg s$^{-1}$) jets may be a significant channel of feedback produced by active galactic nuclei (AGN), but little is known about their actual effect on…

Multi-frequency VLBI observations allow studies of the continuum spectrum in the different parts of the parsec scale jets of AGN, providing information on the physical properties of the plasma and magnetic fields in them. Since VLBI…

Astrophysics · Physics 2009-04-14 T. Savolainen , K. Wiik , E. Valtaoja , M. Tornikoski

Synchrotron self-absorption in active galactic nuclei (AGN) jets manifests itself as a time delay between flares observed at high and low radio frequencies. It is also responsible for the observing frequency dependent change in size and…

Astrophysics of Galaxies · Physics 2019-04-17 Alexander Kutkin , Ilya Pashchenko , Kirill Sokolovsky , Yuri Y. Kovalev , Margo Aller , Hugh Aller

Parsec scale jet properties are shortly presented and discussed. Observational data are used to derive constraints on the jet velocity and orientation, the presence of velocity structures, and the connection between the pc and kpc scale.…

Astrophysics · Physics 2009-11-10 Gabriele Giovannini

Radio outflows of extents ranging from a few parsecs to a few kiloparsecs are present in Seyfert and LINER galaxies that make up the `radio-quiet' AGN class. AGN jets and/or starburst superwinds have been suggested to produce these…

Astrophysics of Galaxies · Physics 2018-07-10 Preeti Kharb

We present 5321 milliarcsecond-resolution total intensity and linear polarization maps of 437 active galactic nuclei (AGNs) obtained with the VLBA at 15 GHz as part of the MOJAVE survey, and also from the NRAO data archive. The former is a…

Astrophysics of Galaxies · Physics 2018-01-18 M. L. Lister , M. F. Aller , H. D. Aller , M. A. Hodge , D. C. Homan , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

Astrometry with the very long baseline radio interferometry (VLBI) allows to determine the position of a point close to the source's brightest compact detail at milliarcsecond scales. For most active galactic nuclei (AGNs), this compact…

High Energy Astrophysical Phenomena · Physics 2025-09-24 A. V. Popkov , Y. Y. Kovalev , A. V. Plavin , L. Y. Petrov , I. N. Pashchenko

The currents carried by the jets of active galactic nuclei (AGNs) can be probed using maps of the Faraday rotation measure (RM), since a jet current will be accompanied by a toroidal magnetic (B) field, which will give rise to a systematic…

Astrophysics of Galaxies · Physics 2018-05-16 Denise C. Gabuzda , Matt Nagle , Naomi Roche

We present the multi-frequency, multi-epoch Very Long Baseline Interferometry (VLBI) study of the two-sided jets in the low-luminosity active galactic nucleus NGC 3998, where physical properties of the jets on parsec scales remain poorly…

Astrophysics of Galaxies · Physics 2025-03-13 Xi Yan , Lang Cui , Luis C. Ho

It is well known that active galactic nuclei (AGN) show various forms of interaction with their host galaxy, in a number of phenomena generally called AGN feedback. In particular, the relativistic plasma jets launched by a fraction of AGN…

Astrophysics of Galaxies · Physics 2021-06-03 Marco Berton , Emilia Järvelä

Imaging relativistic jets in active galactic nuclei (AGN) at angular resolution significantly surpassing that of the ground-based VLBI at centimetre wavelengths is one of the key science objectives of the RadioAstron space-VLBI mission.…

Astrophysics of Galaxies · Physics 2020-01-10 Gabriele Bruni , Tuomas Savolainen , Jose Luis Gómez , Andrei P. Lobanov , Yuri Y. Kovalev

We have investigated the differences in apparent opening angles between the parsec-scale jets of the active galactic nuclei (AGN) detected by the Fermi Large Area Telescope (LAT) during its first three months of operations and those of…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-20 A. B. Pushkarev , Y. Y. Kovalev , M. L. Lister , T. Savolainen

Intensive VLBI monitoring programs of jets in AGN are showing the existence of intricate emission patterns, such as upstream motions or slow moving and quasi-stationary componentes trailing superluminal features. Relativistic hydrodynamic…

Astrophysics · Physics 2007-05-23 J. L. Gomez , J. M. Marti , I. Agudo , A. P. Marscher , S. G. Jorstad , M. A. Aloy