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Related papers: Approaching NGC3079 with VLBI

200 papers

There is growing evidence of relativistic jets in radio-loud narrow-line Seyfert 1 (RL-NLS1) galaxies. We constrain the observational properties of the radio emission in the first RL-NLS1 galaxy ever detected in gamma-rays, PMN J0948+0022,…

We have used the VLBA to produce a high dynamic range image of the nucleus of NGC 6251 at 1.6 GHz and snapshot images at 5.0, 8.4, and 15.3 GHz to search for emission from a parsec-scale counterjet. Previous VLBI images at 1.6 GHz have set…

Astrophysics · Physics 2008-11-26 Dayton L. Jones , Ann E. Wehrle

We present a study of reddening and absorption towards the Narrow Line Regions (NLR) in active galactic nuclei (AGN) selected from the Revised Shapley-Ames, 12mu, and Swift/Burst Alert Telescope samples. For the sources in host galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 S. B. Kraemer , H. R. Schmitt , D. M. Crenshaw , M. Melendez , T. J. Turner , M. Guainazzi. , R. F. Mushotzky

We present radio continuum observations of NGC 2082 using ASKAP, ATCA and Parkes telescopes from 888 MHz to 9000 MHz. Some 20 arcsec from the centre of this nearby spiral galaxy, we discovered a bright and compact radio source,…

Astrophysics of Galaxies · Physics 2022-07-05 Joel C. F. Balzan , Miroslav D. Filipovic , Shi Dai , Rami Z. E. Alsaberi , Luke Barnes

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

Astrometry with the very long baseline radio interferometry (VLBI) allows to determine the position of a point close to the source's brightest compact detail at milliarcsecond scales. For most active galactic nuclei (AGNs), this compact…

High Energy Astrophysical Phenomena · Physics 2025-09-24 A. V. Popkov , Y. Y. Kovalev , A. V. Plavin , L. Y. Petrov , I. N. Pashchenko

In this paper we report the discovery of an hard X-ray selected Type 2 Seyfert galaxy and we present and discuss its X-ray and optical spectrum together with the radio to X-ray energy distribution. The X-ray source - AXJ2254+1146 - is part…

Astrophysics · Physics 2007-05-23 R. Della Ceca , T. Maccacaro , P. Rosati , V. Braito

Historically, Seyfert nuclei have been considered to be radio-quiet active galactic nuclei (AGNs). We question this widely held assumption by showing that the distribution of the radio-to-optical luminosity ratio R, when properly measured…

Astrophysics · Physics 2009-11-06 Luis C. Ho , Chien Y. Peng

We present our recent results about the extended narrow-line region (ENLR) of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212) obtained by modelling the observed line profiles and spectra with composite models (photoionization+shocks)…

We discuss the results of a campaign to monitor spectral variations in the low-luminosity Seyfert~1 galaxy NGC~4593, at X-rays, ultraviolet, optical and near IR frequencies. The observations and data analysis have been described in a…

Astrophysics · Physics 2015-06-24 M. Santos-Lleo , J. Clavel , P. Barr , I. S. Glass , D. Pelat , B. M. Peterson , G. Reichert

Narrow-line Seyfert 1 (NLS1) galaxies are a type of active galactic nuclei (AGN) that were originally classified as sources with little to no radio emission. Although the class is rather unified from an optical perspective, their radio…

Astrophysics of Galaxies · Physics 2025-11-26 I. Varglund , E. Järvelä , M. J. Hardcastle , S. Varglund , A. Lähteenmäki

Observations of the Seyfert 2 and starburst galaxy NGC 5135 with the Chandra X-ray Observatory demonstrate that both of these phenomena contribute significantly to its X-ray emission. We spatially isolate the active galactic nucleus (AGN)…

Astrophysics · Physics 2016-08-30 N. A. Levenson , K. A. Weaver , T. M. Heckman , H. Awaki , Y. Terashima

The nearby Seyfert type galaxy NGC 1275 contains a bright radio nucleus at its center, revealed through high-spatial resolution imaging to be the source of the jets emanating from the galaxy. Coincident with the emergence of a new component…

High Energy Astrophysical Phenomena · Physics 2022-02-16 Pengfei Zhang , Zhongxiang Wang , Mark Gurwell , Paul J. Wiita

The observation of the Narrow-Line Seyfert 1 galaxy IRAS13349+2438 performed by XMM-Newton European Photon Imaging Camera between 0.3-10 keV, is presented here. The broadband spectrum of the source is dominated at low energies (E < 2 keV)…

Astrophysics · Physics 2009-11-10 A. L. Longinotti , M. Cappi , K. Nandra , M. Dadina , S. Pellegrini , ;

We report the results of an XMM-Newton observation of the Narrow-Line Seyfert 1 galaxy Mkn 1239. This optically highly polarized AGN has one of the steepest X-ray spectra found in AGN with alpha-X = +3.0 based on ROSAT PSPC data. The…

Astrophysics · Physics 2009-11-10 D. Grupe , S. Mathur , S. Komossa

We study a complete and distance-limited sample of 25 LINERs, 21 of which have been imaged with the Hubble Space Telescope to study their physical properties and to compare their radio and optical properties with those of other samples of…

Astrophysics · Physics 2015-06-24 F. D. Macchetto , M. Chiaberge

We report the discoveries of a nuclear ring of diameter 10$\arcsec$ ($\sim$1.5 kpc) and a potential low luminosity active galactic nucleus (LLAGN) in the radio continuum emission map of the edge-on barred spiral galaxy NGC~5792. These…

We analyze all the available Atacama Large Millimeter / submillimeter Array archival data of the nearby Type-II Seyfert galaxy NGC 1068, including new 100 GHz data with the angular resolution of 0\farcs05, which was not included in previous…

Astrophysics of Galaxies · Physics 2023-08-02 Tomonari Michiyama , Yoshiyuki Inoue , Akihiro Doi

We use the sample of emission-line nuclei derived from a recently completed optical spectroscopic survey of nearby galaxies to quantify the incidence of local (z = 0) nuclear activity. Consistent with previous studies, we find detectable…

Astrophysics · Physics 2009-10-30 Luis C. Ho , Alexei V. Filippenko , Wallace L. W. Sargent

We present two-dimensional gaseous kinematics of the inner 1.2 $\times$ 1.8 kpc$^2$ of the Seyfert 2 galaxy NGC3081, from optical spectra (5600--7000\r{A}) obtained with the GMOS integral field spectrograph on the Gemini North telescope at…

Astrophysics of Galaxies · Physics 2016-02-03 Allan Schnorr-Müller , Thaisa Storchi-Bergmann , Andrew Robinson , Davide Lena , Neil M. Nagar
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