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Related papers: Unabsorbed Seyfert 2 galaxies

200 papers

We consider the sample of Tran (2001) to study the X-ray properties of Seyfert 2 galaxies with and without polarized broad lines.

Astrophysics · Physics 2007-05-23 Andrea Martocchia , Giorgio Matt

We study the hard X-ray emission of two samples of Seyfert 2 galaxies with and without Polarized Broad Lines (PBL). In the hard X-ray domain, absorption effects do not significantly modify the intrinsic emission allowing us a direct access…

Astrophysics · Physics 2016-08-30 S. J. Deluit

Narrow-line Seyfert 1 galaxies are defined on the basis of their line widths, and they are generally considered to be high Eddington ratio sources. But in the context of the Quasar Main Sequence, high Eddington rate sources are those which…

Astrophysics of Galaxies · Physics 2018-06-19 Bozena Czerny , Swayamtrupta Panda , Marzena Sniegowska , Szymon Kozlowski , Marek Nikolajuk , Pu Du , Bei You

We describe a new sample of Seyfert nuclei discovered during the course of an optical spectroscopic survey of nearby galaxies. The majority of the objects, many recognized for the first time, have luminosities much lower than those of…

Astrophysics · Physics 2007-05-23 Luis C. Ho , Alexei V. Filippenko , Wallace L. W. Sargent

We present the Spitzer 10-37um IRS high resolution (R~600) spectroscopic survey of the Seyfert galaxies of the 12 micron Galaxy Sample. The new spectra of 61 galaxies, with those already published, gives us a total of 91 12micron Seyfert…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Silvia Tommasin , Luigi Spinoglio , Matthew A. Malkan , Giovanni Fazio

The origin of the unification model for Active Galactic Nuclei (AGN) was the detection of broad hydrogen recombination lines in the optical polarized spectrum of the Seyfert 2 galaxy (Sy2) NGC 1068. Since then, a search for the hidden…

We report on BeppoSAX broad band (0.1-100 keV) observations of bright Seyfert 2 galaxies and discuss the results in the framework of the unified theory of AGNs. The data are used to probe Nh distribution in type 2 objects and to identify…

Astrophysics · Physics 2007-05-23 L. Bassani , M. Cappi , G. Malaguti

We present spatially resolved BPT mapping of the extended narrow line regions (ENLRs) of seven nearby Seyfert 2 galaxies, using HST narrow band filter imaging. We construct the BPT diagrams using $\leq$ 0.1" resolution emission line images…

We present 8-13 micron imaging and spectroscopy of 9 type 1 and 10 type 2 AGN obtained with the VLT/VISIR instrument at spatial resolution <100 pc. The emission from the host galaxy sources is resolved out in most cases. The silicate…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. F. Hoenig , M. Kishimoto , P. Gandhi , A. Smette , D. Asmus , W. Duschl , M. Polletta , G. Weigelt

We present Chandra observations of 17 optically-selected, X-ray weak narrow-line Seyfert 1 (NLS1) galaxies. These objects were optically identified by Williams et al. (2002) in the Sloan Digital Sky Survey Early Data Release, but were not…

Astrophysics · Physics 2009-11-10 Rik J. Williams , Smita Mathur , Richard W. Pogge

The optical classification of a Seyfert galaxy and whether it is considered X-ray absorbed are often used interchangeably. But there are many borderline cases and also numerous examples where the optical and X-ray classifications appear to…

In this work we present the most comprehensive INTEGRAL AGN sample which lists 272 objects. Here we mainly use this sample to study the absorption properties of active galaxies, to probe new AGN classes and to test the AGN unification…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Malizia , L. Bassani , A. Bazzano , A. J. Bird , N. Masetti , F. Panessa , J. B. Stephen , P. Ubertini

We report on the analysis of a BeppoSAX observation of IRAS 13197-1627. The complexity of the broad band (0.3-100 keV) spectrum of the source prevents us from selecting from two possible best-fit models, i.e. one based on a partial covering…

Astrophysics · Physics 2009-11-10 Mauro Dadina , Massimo Cappi

We present a study of the intrinsic absorption lines in the ultraviolet spectra of Seyfert 1 galaxies. We find that the fraction of Seyfert 1 galaxies that show absorption associated with their active nuclei is more than one-half (10/17),…

We have examined ROSAT soft X-ray observations of a complete, distance-limited sample of Seyfert and LINER galaxies. X-ray data are available for 46 out of 60 such objects which lie within a hemisphere of radius 18 Mpc. We have constructed…

Astrophysics · Physics 2009-11-06 Eve L. Halderson , Edward C. Moran , Alexei V. Filippenko , Luis C. Ho

(Abridged) We present an unbiassed near-IR selected AGN sample, covering 12.56 square degrees down to K ~ 15.5, selected from the Two Micron All Sky Survey (2MASS). Our only selection effect is a moderate color cut (J-K>1.2) designed to…

Astrophysics · Physics 2009-11-10 Paul J Francis , Brant O. Nelson , Roc M. Cutri

We present new photometry of 16 local Seyferts including 6 Compton-thick sources in N-band filters around 12-microns, obtained with the VISIR instrument on the 8-m Very Large Telescope. The near-diffraction-limited imaging provides the…

Astrophysics of Galaxies · Physics 2015-05-13 P. Gandhi , H. Horst , A. Smette , S. Hoenig , A. Comastri , R. Gilli , C. Vignali , W. Duschl

We have performed a spectroscopic study of 7 Type 2 QSOs using the mid-infrared spectrometer IRS on board the Spitzer Space Telescope. These are (to our knowledge) the first mid-IR spectra of X-ray selected QSO2s taken. The objects have…

Astrophysics · Physics 2009-11-11 E. Sturm , G. Hasinger , I. Lehmann , V. Mainieri , R. Genzel , M. D. Lehnert , D. Lutz , L. J. Tacconi

We present an estimate of the local X-ray luminosity function and emissivity for different subsamples of galaxies namely Seyferts, LINERS, star-forming and passive (no-emission-line) galaxies. This is performed by convolving their optical…

Astrophysics · Physics 2009-10-31 I. Georgantopoulos , S. Basilakos , M. Plionis

We define a new sample of 96 low-redshift (z<0.1), soft X-ray selected Seyferts from the catalog of the Einstein Slew Survey (Elvis etal. 1992, Plummer et al. 1994). We probe the geometry and column depth of obscuring material in the…

Astrophysics · Physics 2009-10-30 Robert Simcoe , K. K. McLeod , Jonathan Schachter , Martin Elvis