Seyfert 2 Galaxies with Spectropolarimetric Observations

Abstract

We present a compilation of radio, infrared, optical and hard X-ray (2-10kev) data for a sample of 90 Seyfert 2 galaxies(Sy2s) with spectropolarimetric observations (41 Sy2s with detection of polarized broad lines (PBL) and 49 without PBL). Compared to Sy2s without PBL, Sy2s with PBL tend to be earlier-type spirals, and show warmer mid-infrared color and significant excess of emissions (including the hard X-ray(2-10kev), [O {\sc iii}]$\lambda$5007, infrared (25 $\mu$m) and radio). Our analyses indicate that the majority of Sy2s without PBL are those sources having less powerful AGN activities, most likely caused by low accretion rate. It implies that the detectability of the polarized broad emission lines in Sy2s may depend on their central AGN activities in most cases. Based on the available data, we find no compelling evidence for the presence of two types of Sy2s, one type of them has been proposed to be intrinsically different from Sy2s claimed in Unification Model.

24 pages, 6 figures, accepted for publication in ApJ

References in corpus (22)

• A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies
• A Structure for Quasars
• The distribution of absorbing column densities among Seyfert 2 galaxies
• The M(BH)-Sigma Relation for Supermassive Black Holes
• A 3 dimensional diagnostic diagram for Seyfert 2s: probing X-ray absorption and Compton thickness
• The Nuclear and Circum-nuclear Stellar Population in Seyfert 2 Galaxies: Implications for the Starburst-AGN Connection
• Hidden Broad Line Seyfert 2 Galaxies in the CfA and 12micron Samples
• The Frequency of Polarized Broad Emission Lines in Type 2 Seyfert Galaxies
• Circumnuclear stellar population, morphology and environment of Seyfert 2 galaxies: an evolutionary scenario
• The frequency of nuclear star-formation in Seyfert 2 galaxies
• A Composite Seyfert 2 X-ray Spectrum: Implications for the Origin of the Cosmic X-ray Background
• X-ray emission from Seyfert 2 galaxies with optical polarized broad lines
• The Unified model and the Seyfert 2 infrared dichotomy
• The infrared luminosity of the torus and the visibility of scattered broad line emission in Seyfert 2 galaxies
• Compton-Thick X-ray Absorption in the Seyfert Galaxies Tololo 0109-383 and ESO 138-G1
• A Polarimetric Search for Hidden Quasars in Three Radio Selected Ultraluminous Infrared Galaxies
• Nuclear obscuration and scattering in Seyfert 2 galaxies
• On the relation between the coronal line emission and the IR/X-ray emission in Seyfert galaxies
• A Hidden Broad-Line Region in the Weak Seyfert 2 Galaxy NGC 788
• Multi-wavelength Study of IRAS 19254-7245 - The Superantennae
• A Possible Evolutionary Connection between AGN and Starburst in LINERs
• Enhanced Star Formation in Seyfert 2 Galaxies

Cited by in corpus (39)

• The star formation history of Seyfert 2 nuclei
• The Lack of BLR in Low Accretion Rate AGN as Evidence of their Origin in the Accretion Disk
• On The Nature of Low Luminosity Narrow Line AGN
• The Link Between the Hidden Broad Line Region and the Accretion Rate in Seyfert 2 Galaxies
• Reflection in Seyfert Galaxies and the Unified Model of AGN
• The Unified Model of Active Galactic Nuclei: II. Evolutionary Connection
• X-ray spectral properties of the AGN sample in the northern XMM-XXL field
• Emission Line Properties of Seyfert 2 Nuclei
• Investigating on the nuclear obscuration in two types of Seyfert 2 galaxies
• Unobscured Type 2 AGNs
• The accretion ratios in Seyfert 2 galaxies with and without hidden broad-line regions
• Constraints on minimum electron Lorentz factor and matter content of jets for a sample of bright Fermi blazars
• The Unified Model of Active Galactic Nuclei: I. Non-hidden Broad Line Region Seyfert 2 and Narrow Line Seyfert 1 Galaxies
• NGC3147: a "true" Seyfert 2 without the broad-line region
• X-ray spectral variability of Seyfert 2 galaxies
• Spectropolarimetry of a Complete Infrared Selected Sample of Seyfert 2 Galaxies
• Compact Nuclear Starbursts in Seyfert 2 Galaxies from the CfA and 12 Micron Samples
• Upholding the Unified Model for Active Galactic Nuclei: VLT/FORS2 Spectropolarimetry of Seyfert 2 galaxies
• Application of the Disk Evaporation Model to AGNs
• Destruction and multiple ionization of PAHs by X-rays in circumnuclear regions of AGNs
• The Different Nature in Seyfert 2 Galaxies With and Without Hidden Broad-Line Regions
• On the origin of the soft photons of the high synchrotron peaked blazar : PKS 1424+240
• The K-band properties of Seyfert 2 galaxies
• Suppressed star formation in circumnuclear regions in Seyfert galaxies
• Compton-thick AGN in the NuSTAR era II: A deep NuSTAR and XMM-Newton view of the candidate Compton thick AGN in NGC 1358
• Detection of Polarized Broad Emission in the Seyfert 2 Galaxy Mrk 573
• On the dichotomy of Seyfert 2 galaxies: intrinsic differences and evolution
• Stellar and gaseous velocity dispersions in type II AGNs at 0.3<z<0.83 from the Sloan Digital Sky Survey
• VISIR/VLT mid-infrared imaging of Seyfert nuclei: Nuclear dust emission and the Seyfert-2 dichotomy
• On the disappearance of broad-line region in low-luminosity active galactic nuclei: the role of the outflows from advection dominated accretion flows
• A Chandra view of Naked Active Galactic Nuclei
• CO line width and the black hole -- bulge relationship at high redshift
• The Diagnostics and Possible Evolution in Active Galactic Nuclei Associated With Starburst Galaxies
• Gas inflows towards the nucleus of NGC1358
• Q2122-444: a naked AGN fully dressed
• Ionization Mechanisms of HBLR and Non-HBLR Seyfert 2 Galaxies
• Digging process in NGC 6951: the molecular disc bumped by the jet
• Are Seyfert 2 Galaxies without Polarized Broad Emission Lines More Obscured?
• On the Structure of the AGN Torus through the Fraction of Optically-Selected Type 1 AGNs