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Related papers: Compact Radio Cores in Seyfert Galaxies

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A radio study of a carefully selected sample of 20 Seyfert galaxies that are matched in orientation-independent parameters, which are measures of intrinsic active galactic nuclei (AGN) power and host galaxy properties is presented to test…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Dharam V. Lal , Prajval Shastri , Denise Gabuzda

Using recent high-resolution radio observations of a large sample of Seyfert galaxies (Roy et al. 1994), we analyze the relations between the compact radio core emission and several nuclear and host galaxy properties. Seyfert nuclei hosted…

Astrophysics · Physics 2008-11-26 Giuliano Giuricin , Dario Fadda , Marino Mezzetti

We report a 0.2" resolution, 15 GHz survey of a sample of 48 low-luminosity active galactic nuclei with the Very Large Array. Compact radio emission has been detected in 57% (17 of 30) of LINERs and low-luminosity Seyferts, at least 15 of…

Astrophysics · Physics 2009-10-31 Neil M. Nagar , Heino Falcke , Andrew S. Wilson , Luis C. Ho

We discuss the properties of compact nuclear radio components in Seyfert galaxies from the extended 12-micron AGN sample of Rush et al.(1993). Our main results can be summarised as follows. Type 1 and type 2 Seyferts produce compact radio…

Astrophysics · Physics 2009-11-06 Andy Thean , Alan Pedlar , Marek J. Kukula , Stefi A. Baum , Christopher P. O'Dea

We have carried out an analysis of the radio and optical properties of a statistical sample of 45 Seyfert galaxies from the Palomar spectroscopic survey of nearby galaxies. We find that the space density of bright galaxies (-22 mag <=…

Astrophysics · Physics 2009-11-06 James S. Ulvestad , Luis C. Ho

This is the first of two papers in which a study is made of a sample of 12 southern radio-luminous Seyfert galaxies. Our aim is to investigate possible correlations between radio morphology and nuclear/circumnuclear emission-line…

Astrophysics · Physics 2009-10-30 M. A. Bransford , P. N. Appleton , C. A. Heisler , R. P. Norris , A. P. Marston

We present optical spectroscopic observations of 93 galaxies taken from the infra-red selected COLA (Compact Objects in Low Power AGN) sample. The sample spans the range of far-IR luminosities from normal galaxies to LIRGs. Of the galaxies…

We present the detection of compact radio structures of fourteen radio-loud narrow line Seyfert 1 (NLS1) galaxies from Very Long Baseline Array observations at 5 GHz, which were performed in 2013. While 50\% of the sources of our sample…

Astrophysics of Galaxies · Physics 2015-10-14 Minfeng Gu , Yongjun Chen , S. Komossa , Weimin Yuan , Zhi-Qiang Shen , Kiyoaki Wajima , Hongyan Zhou , J. A. Zensus

We have observed a sample of Seyfert (Sy) galaxies with the global Very Long Baseline Interferometry (VLBI) to test the predictions of the unification scheme for the Sy galaxies which hypothesises that Sys of Type 1 and of Type 2 constitute…

Astrophysics · Physics 2007-05-23 Dharam Vir Lal

Aims. We present low-frequency radio imaging and spectral properties of a well defined sample of Seyfert galaxies using GMRT 240/610 MHz dual frequency observations. Radio spectra of Seyfert galaxies over 240 MHz to 5.0 GHz are investigated…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-23 Veeresh Singh , Prajval Shastri , Ishwara-Chandra C. H. , Ramana Athreya

We present optical spectropolarimetry of the nuclei of 36 Seyfert 1 galaxies, obtained with the William Herschel and the Anglo-Australian Telescopes from 1996 to 1999. In 20 of these, the optical emission from the active nucleus is…

Astrophysics · Physics 2008-11-26 J. E. Smith , S. Young , A. Robinson , E. A. Corbett , M. E. Giannuzzo , D. J. Axon , J. H. Hough

Seyfert galaxies have traditionally been classified as radio-quiet active galactic nuclei. A proper consideration of the nuclear optical emission however proves that a majority of Seyferts are radio-loud. Kpc-scale radio lobes/bubbles are…

Astrophysics of Galaxies · Physics 2014-03-13 P. Kharb , V. Singh , J. F. Gallimore , C. H. Ishwara-Chandra

We present the results of new radio observations carried out with the Karl G. Jansky Very Large Array C-configuration at 5.5 GHz for a sample of southern narrow-line Seyfert 1 galaxies (NLS1s). This work increases the number of known…

Astrophysics of Galaxies · Physics 2020-09-02 S. Chen , E. Jarvela , L. Crepaldi , M. Zhou , S. Ciroi , M. Berton , P. Kharb , L. Foschini , M. Gu , G. La Mura , A. Vietri

We present the first results from the COLA (Compact Objects in Low-power AGN) project which aims to determine the relationship between one facet of AGN activity, the compact radio core, with star formation in the circumnuclear region of the…

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 this letter, we report on dual-frequency European VLBI Network (EVN) observations of the faintest and least luminous radio cores in Seyfert nuclei, going to sub-mJy flux densities and radio luminosities around 10^19 W/Hz. We detect radio…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Marcello Giroletti , Francesca Panessa

We report the discovery of 164 compact (radius < 1 arcmin) radio rings using MeerKAT 1.3 GHz data from the SARAO MeerKAT Galactic Plane Survey (l=2-60deg, 252-358deg, |b|<1.5deg) and the Galactic Centre mosaic, from a search aimed at…

We present a series of statistical tests done to a sample of 29 Seyfert 1 and 59 Seyfert 2 galaxies selected from mostly isotropic properties, their far infrared fluxes and warm infrared colors. Such selection criteria provide a profound…

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

Seyfert galaxies commonly host compact jets spanning 10-100 pc scales, but larger structures (KSRs) are resolved out in long baseline, aperture synthesis surveys. We report a new, short baseline Very Large Array (VLA) survey of a complete…

Astrophysics · Physics 2008-11-26 J. F. Gallimore , D. J. Axon , C. P. O'Dea , S. A. Baum , A. Pedlar
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