The Detection of Silicate Emission from Quasars at 10 and 18 Microns

Abstract

We report the spectroscopic detection of silicate emission at 10 and 18 microns in five PG quasars, the first detection of these two features in galaxies outside the Local Group. This finding is consistent with the unification model for Active Galactic Nuclei (AGNs), which predicts that an AGN torus seen pole-on should show a silicate emission feature in the mid-infrared. The strengths of the detected silicate emission features range from 0.12 to 1.25 times the continuum at 10 microns and from 0.20 to 0.79 times the continuum at 18 microns. The silicate grain temperatures inferred from the ratio of 18-to-10 micron silicate features under the assumption of optically thin emission range from 140 to 220K.

arXiv comment4 pages, including 2 tables and 3 figures. Accepted by ApJL

References in corpus (12)

• The Spitzer Space Telescope Mission
• Dust Grain Size Distributions and Extinction in the Milky Way, LMC, and SMC
• The Infrared Spectrograph on the Spitzer Space Telescope
• Infrared Emission from Interstellar Dust. II. The Diffuse Interstellar Medium
• What Powers Ultra-luminous IRAS Galaxies?
• Dust Emission from Active Galactic Nuclei
• A large mid-infrared spectroscopic and near-IR imaging survey of ULIRGs: their nature and evolution
• Spectroscopic Redshifts to z > 2 for Optically Obscured Sources Discovered with the Spitzer Space Telescope
• ISOCAM-CVF 5-12 mum Spectroscopy of Ultraluminous Infrared Galaxies
• Observations of Ultraluminous Infrared Galaxies with the Infrared Spectrograph on the Spitzer Space Telescope: Early Results on Mrk 1014, Mrk 463, and UGC 5101
• New radiative transfer models for obscuring tori in active galaxies
• Variability of Quasars at 10 microns

Cited by in corpus (154)

• The Mid-Infrared Spectrum of Star-Forming Galaxies: Global Properties of PAH Emission
• Active Galactic Nuclei: what's in a name?
• Revisiting the Infrared Spectra of Active Galactic Nuclei with a New Torus Emission Model
• Cool Outflows in Galaxies and their Implications
• Observations of Ultraluminous Infrared Galaxies with the Infrared Spectrograph on the Spitzer Space Telescope II: The IRAS Bright Galaxy Sample
• Three-dimensional radiative transfer modeling of AGN dusty tori as a clumpy two-phase medium
• A Two-Parameter Model for the Infrared/Submillimeter/Radio Spectral Energy Distributions of Galaxies and AGN
• Dust covering factor, silicate emission and star formation in luminous QSOs
• Radiative Transfer Modeling of Three-Dimensional Clumpy AGN Tori and its Application to NGC 1068
• Spitzer Quasar and ULIRG evolution study (QUEST): I. The origin of the far infrared continuum of QSOs
• The New Generation Atlas of Quasar Spectral Energy Distributions from Radio to X-rays
• The dusty heart of nearby active galaxies -- II. From clumpy torus models to physical properties of dust around AGN
• Three-dimensional radiative transfer models of clumpy tori in Seyfert galaxies
• Mid-Infrared Spectra of Classical AGN Observed with the Spitzer Space Telescope
• A Near-Infrared Spectral Template for Quasars
• Chandra and Spitzer unveil heavily obscured quasars in the SWIRE/Chandra Survey
• The subarcsecond mid-infrared view of local active galactic nuclei: I. The N- and Q-band imaging atlas
• The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus models
• Smooth and Clumpy Dust Distribution in AGN: a Direct Comparison of two Commonly Explored Infrared Emission Models
• The distribution of silicate strength in Spitzer spectra of AGNs and ULIRGs
• The dusty heart of nearby active galaxies. I. High-spatial resolution mid-IR spectro-photometry of Seyfert galaxies
• Spitzer Observations of 3C Quasars and Radio Galaxies: Mid-Infrared Properties of Powerful Radio Sources
• Star formation in the hosts of high-z QSOs: Evidence from Spitzer PAH detections
• Spitzer Reveals Hidden Quasar Nuclei in Some Powerful FR II Radio Galaxies
• Unveiling a Population of X-ray Non-Detected AGN
• Spitzer IRS spectra of a large sample of Seyfert galaxies: a variety of infrared SEDs in the local AGN population
• 9.7 um Silicate Features in AGNs: New Insights into Unification Models
• Deep Mid-Infrared Silicate Absorption as a Diagnostic of Obscuring Geometry Toward Galactic Nuclei
• Parsec-scale dust distributions in Seyfert galaxies - Results of the MIDI AGN snapshot survey
• A mid-infrared spectroscopic study of submillimeter galaxies: luminous starbursts at high redshift
• Characterizing the Gamma-Ray Variability of the Brightest Flat Spectrum Radio Quasars Observed with the Fermi LAT
• Spatially-resolved mid-infrared spectroscopy of NGC 1068: the nature and distribution of the nuclear material
• Silicate emissions in active galaxies - From LINERs to QSOs
• Spitzer/IRS 5-35 um Low-Resolution Spectroscopy of the 12 um Seyfert Sample
• Aromatic Features in AGN: Star-Forming Infrared Luminosity Function of AGN Host Galaxies
• The SAGE-Spec Spitzer Legacy program: The life-cycle of dust and gas in the Large Magellanic Cloud. Point source classification I
• On the 10-micron silicate feature in Active Galactic Nuclei
• [CII] 158 micron Luminosities and Star Formation Rate in Dusty Starbursts and AGN
• The spectral energy distribution of the central parsecs of the nearest AGN
• SPITZER IRS spectra of Virgo early type galaxies: detection of stellar silicate emission
• The Detection of Crystalline Silicates in Ultra-Luminous Infrared Galaxies
• Carbon-rich dust past the asymptotic giant branch: aliphatics, aromatics, and fullerenes in the Magellanic Clouds
• Shedding New Light on the 3C 273 Jet with the Spitzer Space Telescope
• Mid-infrared Spitzer spectra of X-ray selected Type 2 QSOs: QSO2s are not ULIRGs
• Decomposing Dusty Galaxies. I. Multi-Component Spectral Energy Distribution Fitting
• Silicates in Ultra-Luminous Infrared Galaxies
• Emission from Hot Dust in the Infrared Spectra of Gamma-ray Bright Blazars
• Extended silicate dust emission in PG QSOs
• Properties of dusty tori in AGN: I. The Case of SWIRE/SDSS Quasars
• Unobscured Type 2 AGNs
• The Spitzer Infrared Nearby Galaxies Survey: A High-Resolution Spectroscopy Anthology
• Infrared Spectral Energy Distributions of Seyfert Galaxies: Spitzer Space Telescope Observations of the 12 micron Sample of Active Galaxies
• An atlas of mid-infrared spectra of star-forming and active galaxies
• A mid-infrared spectroscopic atlas of local active galactic nuclei on sub-arcsecond resolution using GTC/CanariCam
• Eight-Dimensional Mid-Infrared/Optical Bayesian Quasar Selection
• Spitzer IRS 16 micron Observations of the GOODS Fields
• Spitzer/IRS Observations of Seyfert 1.8s and 1.9s: A Comparison with Seyfert 1s and Seyfert 2s
• The Mid-Infrared Emission of M87
• Modeling the Dust Properties of z ~ 6 Quasars with ART^2 -- All-wavelength Radiative Transfer with Adaptive Refinement Tree
• Dust emission from a parsec-scale structure in the Seyfert 1 nucleus of NGC 4151
• GOALS-JWST: Mid-Infrared Spectroscopy of the Nucleus of NGC 7469
• Mid-infrared spectra of optically selected type 2 quasars
• Time-resolved infrared emission from radiation-driven central obscuring structures in Active Galactic Nuclei
• Disordered Silicates in Space: a Study of Laboratory Spectra of "Amorphous" Silicates
• The Origin of the Silicate Emission Features in the Seyfert 2 Galaxy, NGC 2110
• The Infrared Emission from the Narrow Line Region
• Optical Line Diagnostics of z~2 Optically Faint ULIRGs in the Spitzer Bootes Survey
• Self-consistent 2-phase AGN torus models: SED library for observers
• Dust Emission from Unobscured Active Galactic Nuclei
• Infrared spectra and photometry of complete samples of PG and 2MASS quasars
• PAH emission and star formation in the host of the z~2.56 Cloverleaf QSO
• A complete census of silicate features in the mid-infrared spectra of active galaxies
• Mid-Infrared Spectroscopic Properties of Ultra-Luminous Infrared Quasars
• Spitzer Mid-IR Spectroscopy of Powerful 2Jy and 3CRR Radio Galaxies. II. AGN Power Indicators and Unification
• Dust in the wind: Crystalline silicates, corundum and periclase in PG 2112+059
• Dusty Tori of Luminous Type 1 Quasars at z \sim 2
• Extinction curve template for intrinsically reddened quasars
• Silicate Emission in the Spitzer IRS spectrum of FSC 10214+4724
• An Investigation into the Effects of Luminosity on the Mid-Infrared Spectral Energy Distributions of Radio-Quiet Quasars
• Mid-infrared spectroscopy of high-redshift 3CRR sources
• Infrared Spectra and Spectral Energy Distributions for Dusty Starbursts and AGN
• Active galactic nucleus torus models and the puzzling infrared spectrum of IRAS F10214+4724
• X-ray radiative transfer in full 3D with SKIRT
• Silicate Dust in Active Galactic Nuclei
• A model for the infrared emission of FSC 10214+4724
• GPU-based Monte Carlo dust radiative transfer scheme applied to AGN
• Infrared Classification and Luminosities For Dusty AGN and the Most Luminous Quasars
• Sweeping Away the Mysteries of Dusty Continuous Winds in AGN
• The dusty tori of nearby QSOs as constrained by high-resolution mid-IR observations
• A temporal study of oxygen-rich pulsating variable AGB star, T Cep: Investigation on dust formation and dust properties
• An Evolutionary Paradigm for Dusty Active Galaxies at Low Redshift
• Exploring the mid-infrared SEDs of six AGN dusty torus models I: synthetic spectra
• A Herschel Study of 24 micron-Selected AGNs and Their Host Galaxies
• Mid-infrared imaging of 25 local AGN with VLT-VISIR
• Chandra and Spitzer observations of CDFS X-ray obscured QSOs
• The extraordinary mid-infrared spectral properties of FeLoBAL Quasars
• The Past and Future of Mid-Infrared Studies of AGN
• Nuclear activity in nearby galaxies: Mid-infrared imaging with the VLT
• 16 micron Imaging around the Hubble Deep Field North with the Spitzer IRS
• Physical Properties of Luminous Dust Poor Quasars
• Active Galactic Nuclei as seen by the Spitzer Space Telescope
• Mid-infrared properties of OH megamaser host galaxies. I: Spitzer IRS low- and high-resolution spectroscopy
• On the dust geometry in radio-loud active galactic nuclei
• Infrared Spectroscopy of CO Ro-vibrational Absorption Lines toward the Obscured AGN IRAS 08572+3915
• The post-Herschel view of intrinsic AGN emission: constructing templates for galaxy and AGN emission at IR wavelengths
• The Relativistic Jet Orientation and Host Galaxy of the Peculiar Blazar PKS 1413+135
• Modelling the strongest silicate emission features of local type 1 AGN
• Average Infrared Galaxy Spectra From Spitzer Flux Limited Samples
• On the Optical-to-Silicate Extinction Ratio as a Probe of the Dust Size in Active Galactic Nuclei
• The Nature of LoBAL QSOs: I. SEDs and mid-infrared spectral properties
• Star formation in AGNs at the hundred parsec scale using MIR high resolution images
• Dust formation in AGN winds
• The Spitzer discovery of a galaxy with infrared emission solely due to AGN activity
• Dust in Active Galactic Nuclei: Anomalous Silicate to Optical Extinction Ratios?
• Far-IR Detection Limits II: Probing Confusion including Source Confusion
• The infrared to X-ray correlation spectra of unobscured type 1 active galactic nuclei
• Modelling the Spoon IRS diagnostic diagram
• From Thin to Thick: The Impact of X-ray Irradiation on Accretion Disks in AGN
• Spectropolarimetry of the 3.4 micron absorption feature in NGC 1068
• An In-Depth View of the Mid-Infrared Properties of Point Sources and the Diffuse ISM in the SMC Giant HII Region, N66
• Probing the High-Redshift Universe with SPICA: Toward the Epoch of Reionization and Beyond
• On the Anomalous Silicate Absorption Feature of the Prototypical Seyfert 2 Galaxy NGC 1068
• On the Anomalous Silicate Emission Features of AGNs: A Possible Interpretation Based on Porous Dust
• The Nature of Deeply Buried Ultraluminous Infrared Galaxies: A Unified Model for Highly Obscured Dusty Galaxy Emission
• Unbiased large spectroscopic surveys of galaxies selected by SPICA using dust bands
• The crystalline fraction of interstellar silicates in starburst galaxies
• Dust composition and mass-loss return from the luminous blue variable R71 in the LMC
• A Tale of Three Galaxies: Anomalous Dust Properties in IRASF10398+1455, IRASF21013-0739 and SDSSJ0808+3948
• Mid-infrared spectroscopy of the Andromeda galaxy
• The role of grain size in AGN torus dust models
• Dust in the Torus of the AGN Unified Model
• Interstellar Silicate Dust in the z=0.685 Absorber Toward TXS 0218+357
• Linking stellar populations to HII regions across nearby galaxies. II. Infrared Reprocessed and UV Direct Radiation Pressure in HII Regions
• The Mid-Infrared Narrow Line Baldwin Effect Revealed by Spitzer
• Hypercubes of AGN Tori (HYPERCAT) -- II. Resolving the Torus with Extremely Large Telescopes
• The mineralogy of newly formed dust in active galactic nuclei
• Characterizing Quasars in the Mid-infrared: High Signal-to-Noise Spectral Templates
• Evolution of the Most Luminous Dusty Galaxies
• Identifying silicate-absorbed ULIRGs at z~1-2 in the Bootes Field using Spitzer/IRS
• The VMC Survey -- XLIX. Discovery of a population of quasars dominated by nuclear dust emission behind the Magellanic Clouds
• HST and Spitzer point source detection and optical extinction in powerful narrow-line radio galaxies
• UV-FIR SED modeling of AGN in IR-luminous galaxies up to z~2.5: Understanding the effects of torus models
• Mid-Infrared and X-ray luminosity correlations of X-ray point sources in NGC 1399
• Constraining the Active Galactic Nucleus and Starburst Properties of the IR-luminous Quasar Host Galaxy APM 08279+5255 at Redshift 4 with SOFIA
• X-ray absorption and 9.7 um silicate feature as a probe of AGN torus structure
• A Complete 16 micron-Selected Galaxy Sample at $z\sim 1$: Mid-infrared Spectral Energy Distributions
• Probing the Interstellar Dust in Galaxies over > 10 Gyr of Cosmic History
• A Tale of Three Galaxies: A "Clumpy" View of the Spectroscopically Anomalous Galaxies IRAS F10398+1455, IRAS F21013-0739 and SDSS J0808+3948
• Early Type Galaxies in the Mid Infrared: a new flavor to their stellar populations
• Dusty Quasars at High Redshifts
• Towards an observationally motivated AGN dusty torus model -- II. The roles of density distribution and chemical composition of the dust
• The study of the circumnuclear environment of accreting supermassive black holes with realistic X-ray spectral models
• A new model for the infrared emission of IRAS F10214+4724
• The Effect of Continuum Elimination in Identifying Circumstellar Dust around Mira