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Related papers: Seyfert 2 Galaxies with Spectropolarimetric Observ…

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We present a sample of 17 type 2 Seyfert galaxies which have an X-ray column density lower than 10^{22} cm^{-2}. The Compton thin nature of these sources is strongly suggested by isotropic indicators. We estimate the fraction of these…

Astrophysics · Physics 2009-11-07 Francesca Panessa , Loredana Bassani

We present mid-infrared data of a sample of 57 AGNs obtained with the instrument ISOCAM on board the satellite ISO. The images were obtained through the LW2 (6.75 microns) and LW7 (9.62 microns) filters. This is a new analysis of Clavel et…

We present an X-ray spectral analysis of a sample of 8 bona-fide Seyfert 2 galaxies, selected on the basis of their high $[OIII]\lambda5007$ flux, from the Ho et al. (1997) spectroscopic sample of nearby galaxies. We find that, in general,…

Astrophysics · Physics 2008-11-26 A. Pappa , I. Georgantopoulos , G. C. Stewart , A. L. Zezas

We study the radio properties at 1.4 GHz of Seyfert galaxies with strong forbidden high-ionization lines (FHILs), selected from the Sloan Digital Sky Survey - a large-sized sample containing nearly equal proportion of diverse range of…

Astrophysics of Galaxies · Physics 2016-01-05 Dharam V. Lal

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

We present sub-arcsec near-infrared 1.5 - 2.5 micron moderate resolution long-slit spectra of eight nearby Seyfert galaxies (z<0.01), both parallel to the ionization cone and perpendicular to it. These spectra complement similar data on six…

Astrophysics · Physics 2009-11-07 J. Reunanen , J. Kotilainen , M. A. Prieto

We present Subaru/FOCAS spectropolarimetry of two active galaxies in the Cosmic Evolution Survey. These objects were selected to be optically dull, with the bright X-ray emission of an AGN but missing optical emission lines in our previous…

Broad-band polarimetry and spectropolarimetry of a complete sample of 18 luminous AGNs (Lbol > 10^11.5 Lsun), selected in an orientation-independent way by warm infrared flux, shows that an orientation-dust-covering Unified Scheme like that…

Astrophysics · Physics 2007-05-23 Beverley J. Wills , Dean C. Hines

The anisotropic nature of active galactic nuclei (AGN) is thought to be responsible for the observational differences between type-1 (pole-on) and type-2 (edge-on) nearby Seyfert-like galaxies. In this picture, the detection of emission…

Astrophysics of Galaxies · Physics 2014-04-10 F. Marin

We present the analysis of morphological and photometric properties of a sample of isolated spirals with (18) and without (11) an active nucleus, based on near-infrared imaging in the J and K' bands. The aim of this analysis is to find the…

The $BeppoSAX$ archive is currently the largest reservoir of high sensitivity simultaneous soft and hard-X ray data of Seyfert galaxies. From this database all the Seyfert galaxies (105 objects of which 43 are type I and 62 are type II)…

Astrophysics · Physics 2009-11-13 Mauro Dadina

We present results of a long-slit spectroscopic study of 39 active and 3 normal galaxies. Stellar absorption features, continuum colors and their radial variations are analyzed in an effort to characterize the stellar population in these…

Astrophysics · Physics 2009-10-30 Roberto Cid Fernandes , Thaisa Storchi-Bergmann , Henrique R. Schmitt

We have analyzed archival \textit{Chandra} and \textit{XMM-Newton} data for two nearly complete homogeneously selected samples of type 2 Seyfert galaxies (Sy2s). These samples were selected based on intrinsic Active Galactic Nuclei (AGN)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Stephanie M. LaMassa , T. M. Heckman , A. Ptak , L. Martins , V. Wild , P. Sonnentrucker , A. Hornschemeier

We have observed a sample of 157 Seyfert galaxies with a 275 km baseline radio interferometer to search for compact, high brightness temperature radio emission from the active nucleus. We obtain the surprising result that compact radio…

Astrophysics · Physics 2009-10-22 A. L. Roy , R. P. Norris , M. J. Kesteven , E. R. Troup , J. E. Reynolds

Near-infrared spectroscopy (rest-frame 3700-6800 Angstroms) of eight high redshift powerful radio galaxies (HzPRGs) at z = 2.2-2.6 is presented. Strong forbidden lines and H-alpha emission were detected in all sources; the data show…

Astrophysics · Physics 2009-10-30 A. S. Evans

We present a deep study of the average hard X-ray spectra of Seyfert galaxies. We analyzed all public INTEGRAL IBIS/ISGRI data available on all the 165 Seyfert galaxies detected at z<0.2. Our final sample consists of 44 Seyfert 1's, 29…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Claudio Ricci , Roland Walter , Thierry J. -L. Courvoisier , Stephane Paltani

We probed the relation between line activities of Seyfert 2 galaxies and their host galaxies. We selected Seyfert 2 galaxies from the Sloan Digital Sky Survey Data Release 10 with redshifts less 0.2. We used the luminosity of the emission…

Astrophysics of Galaxies · Physics 2019-03-12 Yen-Chen Chen , Chorng-Yuan Hwang

This paper contains a list of new AGN candidates identified from the examination of 3500 optical spectra contained in the database of the Southern Sky Redshift Survey Extension (SSRS2). The classification of galaxies was done using standard…

Astrophysics · Physics 2007-05-23 M. A. G. Maia , J. A. Suzuki , L. N. da Costa , C. N. A. Willmer , C. Rite

Large-scale magnetic fields reveal themselves through diffuse synchrotron sources observed in galaxy clusters such as radio halos. Total intensity filaments of these sources have been observed in polarization as well, but only in three…

Although the properties of the narrow-line region (NLR) of active galactic nuclei(AGN) have been deeply studied by many authors in the past three decades, many questions are still open. The main goal of this work is to explore the NLR of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 L. Vaona , S. Ciroi , F. Di Mille , V. Cracco , G. La Mura , P. Rafanelli