相关论文: Optical polarization properties of AGN with signif…
Observational studies of collimation in jets in active galactic nuclei (AGN) are a key to understanding their formation and acceleration processes. We have performed an automated search for jet shape transitions in a sample of 367 AGN using…
We analyze the variability of the parsec-scale jet directions in active galactic nuclei (AGNs). Our analysis involves 317 AGNs at frequencies ranging from 2 to 43 GHz, and is made possible by developing an automatic inner jet direction…
Double-peaked emission lines in the narrow- and/or broad-line spectra of AGN have been suggested to arise due to disky broad/narrow line regions, jet-medium interaction, or the presence of binary supermassive black holes. We present the…
We report on multi-frequency linear polarization monitoring of 15 active galactic nuclei containing highly relativistic jets with apparent speeds from $\sim$4 $c$ to $>40c$. The measurements were obtained at optical, 1 mm, and 3 mm…
Active Galactic Nuclei (AGN) are some of the most luminous and extreme environments in the Universe. The central engines of AGN, believed to be super-massive black-holes, are fed by accretion discs threaded by magnetic fields within a dense…
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.…
(abridged) Relativistic jets, formed in the vicinity of central supermassive black holes in AGN, show ample evidence connecting them to physical conditions in the accretion disc and broad-line region. The jets are responsible for a large…
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…
Gravitational wave (GW) and gravitational slingshot recoil kicks, which are natural products of SMBH evolution in merging galaxies, can produce active galactic "nuclei" that are offset from the centers of their host galaxies. Detections of…
The relationship between galaxies and their supermassive black holes (SMBHs) is an area of active research. One way to investigate this is to compare parsec-scale jets formed by SMBHs with the projected shape of their kiloparsec-scale host…
The optical-ultraviolet continuum from active galactic nuclei (AGN) seem to originate from optically thick and/or thin disks, and occasionally from associated circumnuclear starburst regions. These different possible origins can, in…
Helical magnetic fields embedded in the jets of active galactic nuclei (AGNs) are required by the broad range of theoretical models that advocate for electromagnetic launching of the jets. In most models, the direction of the magnetic field…
Off-nucleus active galactic nuclei (AGN) can be signposts of inspiraling supermassive black holes (SMBHs) on galactic scales, or accreting SMBHs recoiling after the coalescence of a SMBH binary or slingshot from three-body interactions.…
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…
The role of star-formation driven outflows in the obscuration of the central source in the Active Galactic Nuclei (AGN) is discussed. The outflow from a sub-parsec scale accretion disc is numerically modelled for parameters appropriate to…
Radio interferometric observations of Active Galactic Nuclei (AGN) jets reveal the significant linear polarization of their synchrotron radiation that changes with frequency due to the Faraday rotation. It is generally assumed that such…
Active galactic nuclei jets are detected via their radio and/or gamma-ray emissions while the accretion disks are detected by their optical and UV radiation. Observations of the radio and optical luminosities show a strong correlation…
We have cross matched the Gaia Data Release 1 secondary dataset that contains positions of 1.14 billion objects against the most complete to date catalogue of VLBI positions of 11.4 thousand sources, almost exclusively active galactic…
We obtained optical imaging polarimetry with the ACS/HRC aboard the HST of the 9 closest radio-galaxies in the 3C catalogue with an FR I morphology. The nuclear sources seen in direct HST images in these galaxies are found to be highly…
We present our latest results on the connection between accretion rate and relativistic jet power in AGN, by using a large sample which includes mostly blazars, but contains also some radio--galaxies. The jet power can be traced by…