Orientation effects on the near-infrared broad band emission of quasars

Abstract

We recently proposed the equivalent width (EW) of the narrow [OIII]5007Å emission line as an orientation indicator for active galactic nuclei. We tested this method on about $12,300$ optically selected broad line quasars from the SDSS 7th Data Release at redshift $z<0.8$ and with full width at half-maximum values of broad emission lines (H$\alpha$, H$\beta$, and MgII) larger than $2000$ km/s. We now examine their spectral energy distributions (SEDs) using broad band photometry from the near-infrared to the ultraviolet to look for variations in the overall shape as a function of the EW[OIII]. We find that quasars with low EW[OIII] values (close to face-on position) have flatter near-infrared SEDs with respect to sources with high EW[OIII] values (almost edge-on). Moreover, quasars with high EW[OIII] values show a factor of $\sim 2$ lower emission in the UV to quasars with low EW[OIII] values. Our findings indicate that the torus is clumpy and, on average, co-axial with the accretion disc and broad line region, in agreement with the most recent theoretical models for the obscuring torus.

arXiv commentAccepted for publication in MNRAS (8 pages, 4 figures and 2 tables)

References in corpus (38)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Seventh Data Release of the Sloan Digital Sky Survey
• Unified Schemes for Radio-Loud Active Galactic Nuclei
• Correcting for the Effects of Interstellar Extinction
• A Catalog of Quasar Properties from SDSS DR7
• The Sloan Digital Sky Survey Quasar Catalog V. Seventh Data Release
• Present-Day Growth of Black Holes and Bulges: the SDSS Perspective
• AGN Dusty Tori: II. Observational Implications of Clumpiness
• AGN Dusty Tori: I. Handling of Clumpy Media
• Revisiting the Infrared Spectra of Active Galactic Nuclei with a New Torus Emission Model
• Three-dimensional radiative transfer modeling of AGN dusty tori as a clumpy two-phase medium
• The diversity of quasars unified by accretion and orientation
• The close environments of accreting massive black holes are shaped by radiative feedback
• Modeling reverberation mapping data II: dynamical modeling of the Lick AGN Monitoring Project 2008 dataset
• Dust covering factor, silicate emission and star formation in luminous QSOs
• Torus and AGN properties of nearby Seyfert galaxies: Results from fitting IR spectral energy distributions and spectroscopy
• Dusty Structure Around Type-I Active Galactic Nuclei: Clumpy Torus Narrow Line Region and Near-Nucleus Hot Dust
• The dusty heart of nearby active galaxies -- II. From clumpy torus models to physical properties of dust around AGN
• Hot Graphite Dust and the Infrared Spectral Energy Distribution of Active Galactic Nuclei
• Testing the Unification Model for AGN in the Infrared: are the obscuring tori of Type 1 and 2 Seyferts different?
• Dusty winds in active galactic nuclei: reconciling observations with models
• The Role of Molecular Gas in Obscuring Seyfert Active Galactic Nuclei
• The Obscured Fraction of AGN in the XMM-COSMOS Survey: A Spectral Energy Distribution Perspective
• The Structure of the Broad-Line Region In Active Galactic Nuclei. II. Dynamical Modeling of Data from the AGN10 Reverberation Mapping Campaign
• Measuring the Fraction of Obscured Quasars by the Infrared Luminosity of Unobscured Quasars
• Searching For the Physical Drivers of Eigenvector 1: Influence of Black Hole Mass and Eddington Ratio
• AGNfitter: A Bayesian MCMC approach to fitting spectral energy distributions of AGN
• On the 10-micron silicate feature in Active Galactic Nuclei
• On the Gas Content and Efficiency of AGN Feedback in Low-redshift Quasars
• The WISSH quasars Project: II. Giant star nurseries in hyper-luminous quasars
• [O III] Equivalent Width and Orientation Effects in Quasars
• Self-consistent 2-phase AGN torus models: SED library for observers
• Orientation effects on spectral emission features of quasars
• Dusty Tori of Luminous Type 1 Quasars at z \sim 2
• Determining the torus covering factors for a sample of type 1 AGN in the local Universe
• Probing the Active Galactic Nuclei Unified Model Torus Properties in Seyfert Galaxies
• A mid-infrared statistical investigation of clumpy torus model predictions

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