English
Related papers

Related papers: Parsec-scale jet direction evolution in AGNs

200 papers

A number of works reported on the existence of a large scale alignment of the polarization plane of extragalactic sources as well as the alignment of radio-sources structural axes. However, both claims and their interpretation remain…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-18 D. Blinov , C. Casadio , N. Mandarakas , E. Angelakis

The formation of relativistic jets in active galactic nuclei (AGN) is related to accretion on to their central supermassive black holes, and magnetic fields are believed to play a central role in launching, collimating and accelerating the…

Astrophysics of Galaxies · Physics 2017-02-23 Juliana C. Motter , Denise C. Gabuzda

The latest results of the most detailed analysis of multi-epoch polarization-sensitive observations of active galactic nuclei (AGN) jets at parsecs scales by very long baseline interferometry (VLBI) reveal several characteristic patterns of…

High Energy Astrophysical Phenomena · Physics 2024-02-13 R. V. Todorov , E. V. Kravchenko , I. N. Pashchenko , A. B. Pushkarev

We present an analysis of the core linear polarization properties of 387 parsec-scale active galactic nuclei (AGN) jets. Using 15 GHz VLBA data, we revisit the conclusions of the first paper in this series with multi-epoch measurements and…

Astrophysics of Galaxies · Physics 2018-08-16 M. A. Hodge , M. L. Lister , M. F. Aller , H. D. Aller , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

We present results from the highest resolution polarization imaging survey of a complete sample of extragalactic radio sources carried out to date. Our sample consists of a statistically complete flat-spectrum subset of 32 AGNs from the…

Astrophysics · Physics 2009-11-07 Matthew L. Lister

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

The long-term variability study over a range of black hole (BH) mass systems from the microquasars of stellar-mass black holes to the Active Galactic Nuclei (AGNs) of supermassive black holes, in $\gamma$-rays offers new insights into the…

High Energy Astrophysical Phenomena · Physics 2024-10-10 Ajay Sharma , Raj Prince , Debanjan Bose

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

The fine-scale structure and the kinematics of relativistic active galactic nuclei (AGN) jets have been studied by very-long-baseline interferometry at very high resolutions since 1998 at 2 cm wavelength for a sample of over a hundred radio…

Astrophysics · Physics 2014-11-18 Eduardo Ros

We discuss acceleration measurements for a large sample of extragalactic radio jets from the MOJAVE program which studies the parsec-scale jet structure and kinematics of a complete, flux-density-limited sample of Active Galactic Nuclei…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-20 D. C. Homan , M. Kadler , K. I. Kellermann , Y. Y. Kovalev , M. L. Lister , E. Ros , T. Savolainen , J. A. Zensus

We used 15 GHz VLBA observations of 366 sources having at least 5 epochs within a time interval 1995-2013 from the MOJAVE program and/or its predecessor, the 2 cm VLBA Survey. For each source we produced a corresponding stacked image…

High Energy Astrophysical Phenomena · Physics 2015-02-03 Alexander B. Pushkarev , Matthew L. Lister , Yuri Y. Kovalev , Tuomas Savolainen

The combined study of the flaring of Active Galactic Nuclei (AGN) at radio wavelengths and pc-scale jet kinematics with Very Long Baseline Interferometry (VLBI) has led to the view that i) the observed flares are associated with ejections…

High Energy Astrophysical Phenomena · Physics 2023-07-14 Silke Britzen , Michal Zajaček , Gopal-Krishna , Christian Fendt , Emma Kun , Frédéric Jaron , Aimo Sillanpää , Andreas Eckart

We present a study of variability time scales in a large sample of Active Galactic Nuclei at several frequencies between 4.8 and 230 GHz. We investigate the differences of various AGN types and frequencies and correlate the measured time…

(See the complete and formatted abstract in the paper). We report on VLBI monitoring of the low-luminosity AGN (LLAGN) in M81 at 1.7, 2.3, 5, and 8.4GHz. These observations are phase-referenced to the supernova SN1993J (located in the same…

High Energy Astrophysical Phenomena · Physics 2015-05-28 I. Marti-Vidal , J. M. Marcaide , A. Alberdi , M. A. Perez-Torres , E. Ros , J. C. Guirado

The idea that systematic Faraday Rotation gradients across the parsec-scale jets of AGNs can reveal the presence of helical magnetic (B) fields has been around since the early 1990s. These gradients are taken to be due to the systematic…

High Energy Astrophysical Phenomena · Physics 2019-08-19 Mehreen Mahmud , Colm P. Coughlan , Eoin Murphy , Denise C. Gabuzda , Redmond Hallahan

Several multi-frequency polarization studies have shown the presence of systematic Faraday Rotation gradients across the parsec-scale jets of Active Galactic Nuclei (AGN), taken to be due to the systematic variation of the line-of-sight…

Astrophysics · Physics 2007-08-03 Mehreen Mahmud , Denise Gabuzda , Vladislavs Bezrukovs

Blazars are a subclass of radio-loud active galactic nuclei (AGNs), where the jet is aligned close to the line of sight. Blazars emission is dominated by non-thermal processes, where Doppler boosted radiation originates from a relativistic…

High Energy Astrophysical Phenomena · Physics 2021-08-19 Jakub Juryšek , Vitalii Sliusar , Dimitri Moulin , Roland Walter

The jets from active galactic nuclei exhibit stability which seems to be far superior compared to that of terrestrial and laboratory jets. They manage to propagate over distances up to a billion of initial jet radii. Yet this may not be an…

High Energy Astrophysical Phenomena · Physics 2017-06-28 Serguei S. Komissarov

We are investigating the kinematics of jets in active galactic nuclei on parsec scales by studying a representative population of sources. This study is being carried out using the Very Long Baseline Array at 15 GHz, with more than 800…

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 24 months of operations and those of…

High Energy Astrophysical Phenomena · Physics 2012-05-04 A. B. Pushkarev , M. L. Lister , Y. Y. Kovalev , T. Savolainen