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Related papers: Jets in AGN -- New Results from HST and VLA

200 papers

They are weak, they are small, and they are often overlooked, but they are numerous and an ubiquitous sign of accreting black holes: compact radio cores and jets in low-power AGN. Here I summarize our work concerning these radio cores and…

Astrophysics · Physics 2007-05-23 Heino Falcke

In this paper I review the results of our ongoing project to investigate the coupling between accretion disk and radio jet in galactic nuclei and stellar mass black holes. We find a good correlation between the UV bump luminosity and the…

Astrophysics · Physics 2015-06-24 Heino Falcke

Compact radio cores are not only common in radio galaxies and quasars but also in many nearby galaxies with low-active, supermassive black holes. One famous example is the Galactic Center source Sgr A*. Recent studies of proper motions and…

Astrophysics · Physics 2007-05-23 Heino Falcke

In order to further test our hypothesis that jets and disk around compact accreting objects are symbiotic features we investigate the newly discovered superluminal galactic radio jets GRS 1915+105 and GRO J1655-40 and the two famous…

Astrophysics · Physics 2007-05-23 Heino Falcke , Peter L. Biermann

We report on the JVLA observations of three high redshift Active Galactic Nuclei (AGN), having a black hole mass estimated to be among the largest known. Two of them, SDSS J0100+2802 and SDSS J0306+1853 at redshift 6.326 and 5.363…

High Energy Astrophysical Phenomena · Physics 2021-12-01 Tullia Sbarrato , Gabriele Ghisellini , Gabriele Giovannini , Marcello Giroletti

Compact relativistic jets in active galactic nuclei offer an effective tool for investigating the physics of nuclear regions in galaxies. The emission properties, dynamics, and evolution of jets in AGN are closely connected to the…

Astrophysics · Physics 2008-11-26 Andrei Lobanov

Seyfert galaxies and quasars were first discovered through optical and radio techniques, but in recent years high-energy emission, that can penetrate central gas and dust, has become essentially the defining characteristic of an AGN. AGNs…

Astrophysics · Physics 2007-05-23 D. M. Worrall

We present 1-7 GHz high-resolution radio imaging (VLA and e-MERLIN) and spatially-resolved ionized gas kinematics for ten z<0.2 type~2 `obscured' quasars (log [L(AGN)/(erg/s)]>~45) with moderate radio luminosities (log…

Relativistic jets are one of the most powerful manifestations of the release of energy produced around supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Orienti , F. D'Ammando , M. Giroletti , D. Dallacasa , T. Venturi , G. Giovannini

Only in the radio-loud population of active galactic nuclei (AGN) does the production, collimation, and acceleration of powerful relativistic jets take place. We introduce here a concept of combined VLBI- and X-ray spectroscopic…

Astrophysics · Physics 2007-05-23 M. Kadler , E. Ros , J. Kerp , A. L. Roy , A. P. Marscher , J. A. Zensus

Relativistic jets are one of the most powerful manifestations of the release of energy related to the supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…

High Energy Astrophysical Phenomena · Physics 2015-04-14 M. Orienti

This article gives a brief historical introduction and reviews our current understanding of jets in radio galaxies and quasars from an observational perspective, with an emphasis on observations at radio wavelengths. Recent results on the…

Astrophysics of Galaxies · Physics 2022-12-21 D. J. Saikia

(Abridged) In this article, we discuss the state of ``AGN feedback'' in radio-quiet (RQ) AGN. This study involves heterogeneous samples of nearby Seyfert and LINER galaxies as well as QSOs that have been observed at low radio frequencies…

Astrophysics of Galaxies · Physics 2023-02-15 Preeti Kharb , Silpa Sasikumar

Jets are a ubiquitous part of the accretion process, seen in a wide variety of objects ranging from active galaxies (AGN) to X-ray binary stars and even newly formed stars. AGN jets are accelerated by the supermassive black hole of their…

We discuss radio observations of a sample of radio-weak and radio-intermediate quasars which demonstrate that - just like their radio-loud counterparts - radio-weak quasars too have relativistic jets in their nuclei. Moreover, a VLA survey…

Astrophysics · Physics 2007-05-23 Heino Falcke , A. S. Wilson , L. C. Ho

We have used the VLBA at 5 GHz to observe all galaxies with nuclear radio flux densities above 3.5 mJy found in a VLA survey at 15 GHz of a sample of nearby LINER galaxies. All galaxies were detected revealing high brightness temperature…

Astrophysics · Physics 2009-10-31 Heino Falcke , Neil M. Nagar , Andrew S. Wilson , James S. Ulvestad

The nuclei of most normal galaxies contain supermassive black holes, which can accrete gas through a disk and become active. These Active Galactic Nuclei, AGN, can form jets which are observed on scales from AU to Mpc and from meter…

High Energy Astrophysical Phenomena · Physics 2019-09-11 Roger Blandford , David Meier , Anthony Readhead

We have surveyed two large samples of nearby low-luminosity AGN with the VLA to search for flat-spectrum radio cores, similar to Sgr A* in the Galactic Center. Roughly one third of all galaxies are detected (roughly one half if HII…

Astrophysics · Physics 2015-06-24 Heino Falcke , Neil M. Nagar , Andrew S. Wilson , Luis C. Ho , Jim S. Ulvestad

Extragalactic radio sources, including quasars, are now typically understood as being produced by a pair of nearly symmetric, oppositely directed relativistic jets. While some these sources span megaparsecs, and are thus the largest…

Astrophysics · Physics 2007-05-23 Paul J. Wiita

Jets are ubiquitous in accreting black holes. Often ignored, they may be a major contributor to the emitted spectral energy distribution for sub-Eddington black holes. For example, recent observations of radio-to-X-ray correlations and…

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