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Related papers: Parsec-scale Nuclear Radio Structures in Seyfert G…

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We have discovered kiloparsec-scale extended radio emission in three narrow-line Seyfert 1 galaxies (NLS1s) in sub-arcsecond resolution 9 GHz images from the Karl G. Jansky Very Large Array (VLA). We find all sources show two-sided, mildly…

Astrophysics of Galaxies · Physics 2015-02-16 Joseph L. Richards , Matthew L. Lister

Narrow-Line Seyfert 1 (NLS1) class of active galactic nuclei (AGNs) is generally radio-quiet, but a small percent of them are radio-loud. The recent discovery by Fermi/LAT of high-energy gamma-ray emission from 4 NLS1s proved the existence…

We probe the role that the directional asymmetry, between relativistic outflows and kilo-parsec scale jets, play in the acceleration of cosmic rays. For this reason we use two powerful, nearby Active Galactic Nuclei (AGNs). These radio…

High Energy Astrophysical Phenomena · Physics 2012-09-06 Nectaria A. B. Gizani

The presence of multi-phase outflows in low ionisation nuclear emission-line regions (LINERs) has been confirmed to be frequent, but the mechanisms that launch them are still under study. We aim to explore the connections between the…

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…

Galactic superwinds occur in almost all infrared-luminous galaxies with star formation rates (SFRs) above 10 M_sun/yr, as shown by studies of the NaI D interstellar absorption line. We demonstrate that this result also applies to…

Astrophysics · Physics 2009-11-13 David S. Rupke , Sylvain Veilleux , D. B. Sanders

Large scale, weakly collimated outflows are very common in galaxies with large infrared luminosities. In complex systems in particular, where intense star formation (SF) coexists with an active galactic nucleus (AGN), it is not clear yet…

Astrophysics of Galaxies · Physics 2015-10-21 Claudio Melioli , Elisabete M. de Gouveia Dal Pino

[Abridged] We combine extensive spatially-resolved multi-wavelength observations, taken as part of the Close AGN Reference Survey (CARS), for the edge-on disc galaxy HE1353-1917 to characterize the impact of the AGN on its host galaxy via…

Broad Balmer emission lines in active galactic nuclei (AGN) may display dramatic changes in amplitude, even disappearance and re-appearance in some sources. As a nearby galaxy at a redshift of z = 0.0264, Mrk 590 suffered such a cycle of…

High Energy Astrophysical Phenomena · Physics 2021-01-20 J. Yang , I. van Bemmel , Z. Paragi , S. Komossa , F. Yuan , X. Yang , T. An , J. Y. Koay , C. Reynolds , J. B. R. Oonk , X. Liu , Q. Wu

Very long baseline interferometry (VLBI) observations show that some active galactic nuclei (AGN) jets exhibit bending even at parsec scales. The nature of bending is comprehensively analysed only for a small number of individual AGN, and…

High Energy Astrophysical Phenomena · Physics 2023-10-05 V. A. Makeev , Y. Y. Kovalev , A. B. Pushkarev

Previous studies of the Na I D interstellar absorption line doublet have shown that galactic winds occur in most galaxies with high infrared luminosities. However, in infrared-bright composite systems where a starburst coexists with an…

Astrophysics of Galaxies · Physics 2014-11-20 Hannah B. Krug , David S. N. Rupke , Sylvain Veilleux

This article focuses on certain variability and emission characteristics of Active Galactic Nuclei (AGN), especially their radio-loud subset consisting of quasars, BL Lacs and $\gamma$-ray detected narrow-line Seyfert 1 galaxies, all of…

Astrophysics of Galaxies · Physics 2019-06-28 Gopal-Krishna , Silke Britzen , Paul Wiita

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

It was once common to regard Seyfert and starburst galaxies as completely different types of object, but there is growing recognition that these classifications refer to the extremes of a continuous spectrum of galaxy types. In a previous…

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

Double-peaked emission line AGN (DPAGN) have been regarded as binary black hole candidates. We present here results from parsec-scale radio observations with the Very Long Baseline Array (VLBA) of five DPAGN belonging to the KISSR sample of…

Astrophysics of Galaxies · Physics 2021-10-04 P. Kharb , S. Subramanian , M. Das , S. Vaddi , Z. Paragi

(Abridged) Spiral galaxies often have extended outflows that permeate beyond the region of the disk. Such outflows have been seen both in starburst galaxies, actively star forming galaxies and galaxies with an AGN. In the latter galaxies it…

Astrophysics · Physics 2008-11-26 T. P. Robitaille , J. Rossa , D. J. Bomans , R. P. van der Marel

Outflows accelerated by AGN are commonly observed in the form of coherent, mildly collimated high-velocity gas directed along the AGN ionisation cones and kinetically powerful (>$10^{44-45}$ erg/s) jets. Recent works found that outflows can…

We report the detection of an intriguing parsec-scale radio source in the "offset AGN" candidate, KISSR 102. The elliptical host galaxy includes two optical nuclei at a projected separation of 1.54 kpc, N1 and N2, to the south-east and…

Astrophysics of Galaxies · Physics 2020-02-19 P. Kharb , D. Lena , Z. Paragi , S. Subramanian , S. Vaddi , M. Das , Rubinur K.

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…