The distribution of absorbing column densities among Seyfert 2 galaxies

Abstract

We use hard X-ray data for an "optimal" sample of Seyfert 2 galaxies to derive the distribution of the gaseous absorbing column densities among obscured active nuclei in the local Universe. Of all Seyfert 2 galaxies in the sample, 75% are heavily obscured (N_H > 10^23 cm^-2) and about half are Compton thick (N_H > 10^24 cm^-2). Intermediate type 1.8-1.9 Seyferts are characterized by an average N_H much lower than "strict" Seyfert 2s. No correlation is found between N_H and the intrinsic luminosity of the nuclear source. This N_H distribution has important consequences for the synthesis of the cosmic X-ray background. Also, the large fraction of Compton thick objects implies that most of the obscuring gas is located within a radius of a few 10 pc from the nucleus.

arXiv comment16 LaTeX pages+5 postscript figures, accepted by ApJ

References in corpus (7)

• A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies
• A Hubble Space Telescope Imaging Survey of Nearby Active Glactic Nuclei
• A 3 dimensional diagnostic diagram for Seyfert 2s: probing X-ray absorption and Compton thickness
• Thick tori around AGN: the case for extended tori and consequences for their X-ray and IR emission
• Seyfert Activity and Nuclear Star Formation in the Circinus Galaxy
• Obscuration in the Host Galaxies of Soft X-ray Selected Seyferts
• The BeppoSAX Deep Surveys

Cited by in corpus (417)

• A Unified, Merger-Driven Model for the Origin of Starbursts, Quasars, the Cosmic X-Ray Background, Supermassive Black Holes and Galaxy Spheroids
• X-ray spectral modelling of the AGN obscuring region in the CDFS: Bayesian model selection and catalogue
• Local Supermassive Black Holes, Relics of Active Galactic Nuclei and the X-ray Background
• An Observational Determination of the Bolometric Quasar Luminosity Function
• Cosmological Evolution of the Hard X-ray AGN Luminosity Function and the Origin of the Hard X-ray Background
• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• Spectral Energy Distributions of Hard X-ray selected AGNs in the XMDS Survey
• AGN Dusty Tori: II. Observational Implications of Clumpiness
• The Chandra Deep Field-North Survey. XIII. 2 Ms Point-Source Catalogs
• Toward the Standard Population Synthesis Model of the X-Ray Background: Evolution of X-Ray Luminosity and Absorption Functions of Active Galactic Nuclei Including Compton-Thick Populations
• What Drives the Growth of Black Holes?
• The physics of galactic winds driven by active galactic nuclei
• Deep Extragalactic X-ray Surveys
• The HELLAS2XMM survey. VII. The hard X-ray luminosity function of AGN up to z=4: more absorbed AGN at low luminosities and high redshifts
• The X-ray Spectral Properties of SCUBA Galaxies
• Dust in active nuclei. I. Evidence for "anomalous" properties
• X-ray spectral properties of AGN in the Chandra Deep Field South
• Absorption Properties and Evolution of Active Galactic Nuclei
• Chandra Snapshot Observations of Low-Luminosity AGNs with a Compact Radio Source
• JADES. The diverse population of infant Black Holes at 4<z<11: merging, tiny, poor, but mighty
• Ubiquitous variability of X-ray absorbing column densities in Seyfert 2 Galaxies
• The XMM-Newton wide-field survey in the COSMOS field: I. Survey description
• On the X-ray, optical emission line and black hole mass properties of local Seyfert galaxies
• Resolving the mid-infrared cores of local Seyferts
• A semi-empirical simulation of the extragalactic radio continuum sky for next generation radio telescopes
• Three years Swift-BAT Survey of AGN: reconciling theory and observations?
• The Space Density of Compton Thick AGN and the X-ray Background
• Obscuration-dependent evolution of Active Galactic Nuclei
• Space density of optically-selected type 2 quasars
• Narrow-line region gas kinematics of 24,264 optically-selected AGN: the radio connection
• Swift BAT Survey of AGN
• Extreme X-ray spectral variability in the Seyfert 2 Galaxy NGC 1365
• Fueling Low-Level AGN Activity Through the Stochastic Accretion of Cold Gas
• The Relationship of Hard X-ray and Optical Line Emission in Low Redshift Active Galactic Nuclei
• X-ray obscuration and obscured AGN in the local universe
• Dust covering factor, silicate emission and star formation in luminous QSOs
• Study of the X-Ray Background Spectrum and its Large-Scale Fluctuation with ASCA
• Most Supermassive Black Holes must be Rapidly Rotating
• The luminosity dependence of the Type 1 AGN fraction
• Changing look: from Compton-thick to Compton-thin, or the re-birth of fossil AGN
• Cold Molecular Outflows in the Local Universe
• Torus and AGN properties of nearby Seyfert galaxies: Results from fitting IR spectral energy distributions and spectroscopy
• A Classic Type 2 QSO
• X-ray Spectral Survey with XMM--Newton of a Complete Sample of Nearby Seyfert Galaxies
• Quasars: the characteristic spectrum and the induced radiative heating
• Towards a Complete Census of AGNs in Nearby Galaxies: A Large Population of Optically Unidentified AGNs
• Dust in active nuclei. II. Powder or gravel?
• Stellar and Quasar Feedback in Concert: Effects on AGN Accretion, Obscuration, and Outflows
• Radio imaging of the Subaru/XMM-Newton Deep Field - I. The 100-microJy catalogue, optical identifications, and the nature of the faint radio source population
• Chandra and Spitzer unveil heavily obscured quasars in the SWIRE/Chandra Survey
• The Blast Wave Model for AGN Feedback: Effects on AGN Obscuration
• Spitzer Power-law AGN Candidates in the Chandra Deep Field-North
• The active nuclei of z<1.0 3CRR radio sources
• The Chandra Deep Field North Survey. VI. The Nature of the Optically Faint X-ray Source Population
• Testing current synthesis models of the X-ray background
• The X-ray spectra of Compton-thick Seyfert 2 galaxies as seen by BeppoSAX
• The evolution of AGN across cosmic time: what is downsizing?
• Hidden Broad Line Seyfert 2 Galaxies in the CfA and 12micron Samples
• An X-ray view of 82 LINERs with Chandra and XMM-Newton data
• Testing the Unification Model for AGN in the Infrared: are the obscuring tori of Type 1 and 2 Seyferts different?
• The Chandra Deep Field-North Survey. XIV. X-ray detected Obscured AGNs and Starburst Galaxies in the Bright Submm Source Population
• Unabsorbed Seyfert 2 galaxies
• Radiative efficiency, variability and Bondi accretion onto massive black holes: from mechanical to quasar feedback in brightest cluster galaxies
• Suzaku Observations of Active Galactic Nuclei Detected in the Swift/BAT Survey: Discovery of "New Type" of Buried Supermassive Black Holes
• On the Unification of Active Galactic Nuclei
• The Evolution of Obscuration in AGN
• Faint high-redshift AGN in the Chandra Deep Field South: the evolution of the AGN luminosity function and black hole demography
• Obscured AGN and the X-ray, Optical and Far-Infrared Number Counts of AGN in the GOODS Fields
• The Role of Molecular Gas in Obscuring Seyfert Active Galactic Nuclei
• The Unified Model & Evolution of Active Galaxies: Implications from a Spectropolarimetric Study
• The Accretion History of AGN I: Supermassive Black Hole Population Synthesis Model
• Host Galaxy Properties of the Swift BAT Ultra Hard X-ray Selected AGN
• Compton Thick AGN: the dark side of the X-ray background
• Deep Silicate absorption features in Compton-thick AGN predominantly arise due to dust in the host galaxy
• Seyfert galaxies in the local Universe (z$\le$ 0.1): the average X-ray spectrum as seen by $BeppoSAX$
• New Indicators for AGN Power: The Correlation Between [O IV] lambda 25.89 micron and Hard X-ray Luminosity for Nearby Seyfert Galaxies
• Optical Identification of the ASCA Large Sky Survey
• Unveiling a Population of X-ray Non-Detected AGN
• Measuring the Fraction of Obscured Quasars by the Infrared Luminosity of Unobscured Quasars
• The MAGNUM survey: different gas properties in the outflowing and disk components in nearby active galaxies with MUSE
• The XMM Deep survey in the CDFS I. First results on heavily obscured AGN
• The Chandra COSMOS-Legacy survey: Source X-ray spectral properties
• Elusive Active Galactic Nuclei
• The Frequency of Polarized Broad Emission Lines in Type 2 Seyfert Galaxies
• 9.7 um Silicate Features in AGNs: New Insights into Unification Models
• Reliable Identification of Compton-thick Quasars at z~2: Spitzer Mid-IR spectroscopy of HDF-oMD49
• Observations of Seyferts by OSSE and parameters of their X-ray/gamma-ray sources
• Connecting the cosmic infrared background to the X-ray background
• Study on X-ray Spectra of Obscured AGNs based on Monte Carlo simulation - an interpretation of observed wide-band spectra
• Less than 10 percent of star formation in z=0.6 massive galaxies is triggered by major interactions
• High Density Reflection Spectroscopy: II. the Density of the Inner Black Hole Accretion Disc in AGN
• The Toroidal Obscuration of Active Galactic Nuclei
• The Chandra view of the 3C/FRI sample of low luminosity radio-galaxies
• Penetrating the Deep Cover of Compton Thick Active Galactic Nuclei
• Fe-K line probing of material around the AGN central engine with Suzaku
• AGN Obscuration and the Unified Model
• On The Nature of Low Luminosity Narrow Line AGN
• The Origins of AGN Obscuration: The 'Torus' as a Dynamical, Unstable Driver of Accretion
• The NuSTAR View of Nearby Compton-thick AGN: The Cases of NGC 424, NGC 1320 and IC 2560
• The fraction of Compton-thick sources in an INTEGRAL complete AGN sample
• Chandra X-ray and Hubble Space Telescope Imaging of Optically Selected kiloparsec-Scale Binary Active Galactic Nuclei I. Nature of the Nuclear Ionizing Sources
• XMM and Chandra measurements of the AGN intrinsic absorption: dependence on luminosity and redshift
• Narrow Iron K$\alpha$ Lines in Active Galactic Nuclei: Evolving Populations?
• AGN Obscuring Tori Supported by Infrared Radiation Pressure
• Supermassive Black Holes at High Redshift are Expected to be Obscured by their Massive Host Galaxies' Inter Stellar Medium
• Optical Spectroscopy of X-ray sources in the Extended Chandra Deep Field South
• Compton thick active galactic nuclei in Chandra surveys
• The cosmological properties of AGN in the XMM-Newton Hard Bright Survey
• The evolution of the Compton thick fraction and the nature of obscuration for AGN in the Chandra Deep Field South
• Obscured star formation in intermediate-density environments: A Spitzer study of the Abell 901/902 supercluster
• Testing the Unified Model with an Infrared Selected Sample of Seyfert Galaxies
• Connecting Galaxy Evolution, Star Formation and the X-ray Background
• AEGIS: Demographics of X-ray and Optically Selected AGNs
• Statistical properties of local active galactic nuclei inferred from the RXTE 3-20 keV all-sky survey
• Radiation fields of disk, BLR and torus in quasars and blazars: implications for gamma-ray absorption
• Reflection in Seyfert Galaxies and the Unified Model of AGN
• The X-ray to [Ne V]3426 flux ratio: discovering heavily obscured AGN in the distant Universe
• AGN are cooler than you think: the intrinsic far-IR emission from QSOs
• XMM-Newton observations of the Lockman Hole IV: spectra of the brightest AGN
• The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN
• X-ray spectral analyses of AGNs from the 7Ms Chandra Deep Field-South survey: the distribution, variability, and evolution of AGN's obscuration
• An Energetic AGN Outburst Powered by a Rapidly Spinning Supermassive Black Hole or an Accreting Ultramassive Black Hole
• X-ray properties of Red Active Galactic Nuclei
• Galaxy gas as obscurer: II. Separating the galaxy-scale and nuclear obscurers of Active Galactic Nuclei
• The XMM-Newton HBS28 sample: studying the obscuration in hard X-ray selected AGNs
• The NuSTAR Extragalactic Survey: A First Sensitive Look at the High-Energy Cosmic X-ray Background Population
• BAT X-ray Survey - III: X-ray Spectra and Statistical Properties
• The X-ray spectra of optically selected Seyfert 2 galaxies. Are there any Sy2 galaxies with no absorption?
• The Chandra Multiwavelength Project: Optical Followup of Serendipitous Chandra Sources
• On the relation of optical obscuration and X-ray absorption in Seyfert galaxies
• The Seyfert-Starburst Connection in X-rays. II. Results and Implications
• X-ray spectral properties of the AGN sample in the northern XMM-XXL field
• Compton thick AGN in the NuSTAR era
• Is there an upper limit to black hole masses?
• Extragalactic H_2O masers and X-ray absorbing column densities
• GASP III. JO36: a case of multiple environmental effects at play?
• Comparison of Nuclear Starburst Luminosities between Seyfert 1 and 2 Galaxies Based on Near-infrared Spectroscopy
• Spitzer Number Counts of AGN in the GOODS fields
• An XMM-Newton spectral survey of 12 micron selected galaxies. II. Implications for AGN selection and unification
• The BeppoSAX High Energy Large Area Survey HELLAS, III: testing synthesis models for the X-ray background
• Line Shifts, Broad-Line Region Inflow, and the Feeding of AGNs
• A Full Year's Chandra Exposure on SDSS Quasars from the Chandra Multiwavelength Project
• Mid-infrared luminous quasars in the GOODS-Herschel fields: a large population of heavily-obscured, Compton-thick quasars at z~2
• Unveiling the nature of Ultraluminous Infrared Galaxies with 3-4 micron spectroscopy
• Determining the covering factor of Compton-thick active galactic nuclei with NuSTAR
• XMM-Newton observations of Seyfert galaxies from the Palomar spectroscopic survey: the X-ray absorption distribution
• Extended silicate dust emission in PG QSOs
• The Chandra COSMOS Legacy Survey: Compton Thick AGN at high redshift
• The INTEGRAL/IBIS AGN catalogue I: X-ray absorption properties versus optical classification
• The Sudden Death of the Nearest Quasar
• Unobscured Type 2 AGNs
• How are AGN Found?
• Traces of past activity in the Galactic Centre
• Revealing the heavily obscured AGN population of High Redshift 3CRR Sources with Chandra X-ray Observations
• An enhanced rate of tidal disruptions in the centrally overdense E+A galaxy NGC 3156
• The accretion ratios in Seyfert 2 galaxies with and without hidden broad-line regions
• NuSTAR Reveals Extreme Absorption in z < 0.5 Type 2 Quasars
• Prevalence of High X-ray Obscuring Columns among AGN that Host H${}_2$O Masers
• Discovery of Kiloparsec Extended Hard X-ray Continuum and Fe K alpha from the Compton Thick AGN ESO428-G014
• X-ray background synthesis: the infrared connection
• NuSTAR observations of water megamaser AGN
• Extreme X-ray Iron Lines in Active Galactic Nuclei
• Nonthermal phenomena in clusters of galaxies
• Submillimetre observations of WISE-selected high-redshift, luminous, dusty galaxies
• The Chandra-COSMOS survey IV: X-ray spectra of the bright sample
• INTEGRAL/IBIS Extragalactic survey: 20-100 keV selected AGN
• Lifting the Veil on Obscured Accretion: Active Galactic Nuclei Number Counts and Survey Strategies for Imaging Hard X-ray Missions
• Star formation and nuclear activity in luminous infrared galaxies: An infrared through radio review
• Why Are AGN and Host Galaxies Misaligned?
• NuSTAR Observations of Heavily Obscured Quasars at z ~ 0.5
• Near-infrared and Millimeter Constraints on the Nuclear Energy Source of the Infrared Luminous Galaxy NGC 4418
• XMM-Newton Observations of a Complete Sample of Optically Selected Type 2 Seyfert Galaxies
• The Multitude of Unresolved Continuum Sources at 1.6 microns in Hubble Space Telescope images of Seyfert Galaxies
• Observational constraints on the spin of the most massive black holes from radio observations
• Fitting LINER nuclei within the AGN family: A matter of obscuration?
• Warped accretion disks and the unification of Active Galactic Nuclei
• NuSTAR Observations of the Compton-thick Active Galactic Nucleus and Ultraluminous X-ray Source Candidate in NGC 5643
• A Multi-Wavelength Study of the Nature of Type 1.8/1.9 Seyfert Galaxies
• A Compton-thick AGN at z~5 in the 4 Ms Chandra Deep Field South
• Are there reliable methods to estimate the nuclear orientation of Seyfert galaxies?
• The broad-band spectrum of 3C 120 observed by BeppoSAX
• Modeling the Nuclear Infrared Spectral Energy Distribution of Type II Active Galactic Nuclei
• Detection of a High Brightness Temperature Radio Core in the AGN-Driven Molecular Outflow Candidate NGC 1266
• X-ray Spectral Constraints for z~2 Massive Galaxies: The Identification of Reflection-Dominated Active Galactic Nuclei
• Quasar Evolution and the Baldwin Effect in the Large Bright Quasar Survey
• The Unified Model of Active Galactic Nuclei: I. Non-hidden Broad Line Region Seyfert 2 and Narrow Line Seyfert 1 Galaxies
• Seyfert 2 Galaxies with Spectropolarimetric Observations
• Non-thermal hard X-ray emission in galaxy clusters observed with the BeppoSAX PDS
• Adaptive Optics Imaging of QSOs with Double-Peaked Narrow Lines: Are they Dual AGNs?
• On the nature of unabsorbed Seyfert 2 galaxies
• X-ray spectra of XMM-Newton serendipitous medium flux sources
• Deep Chandra Observations of ESO 428-G014: III. High Resolution Spectral Imaging of the Ionization Cone and Radio Jet Region
• 3-D Radiative Transfer Calculations of Radiation Feedback from Massive Black Holes: Outflow of Mass from the Dusty "Torus"
• Connecting Dark Matter Halos with the Galaxy Center and the Supermassive Black Hole
• The Chandra View of Galaxy Mergers
• A Composite Seyfert 2 X-ray Spectrum: Implications for the Origin of the Cosmic X-ray Background
• Structure of the Circumnuclear Region of Seyfert 2 Galaxies Revealed by RXTE Hard X-ray Observations of NGC 4945
• Does the obscured AGN fraction really depend on luminosity?
• Uncovering Obscured Active Galactic Nuclei in Homogeneously Selected Samples of Seyfert 2 Galaxies
• Multiphase gas flows in the nearby Seyfert galaxy ESO428-G14
• Radiation-driven outflows from and radiative support in dusty tori of active galactic nuclei
• Searching for Compton-thick active galactic nuclei at z~0.1
• Cumulative hard X-ray spectrum of local AGN: a link to the cosmic X-ray background
• Discovery of Water Maser Emission in Five AGN and a Possible Correlation Between Water Maser and Nuclear 2-10 keV Luminosities
• The complex iron line of NGC 5506
• The Chandra Deep Fields: Lifting the Veil on Distant Active Galactic Nuclei and X-Ray Emitting Galaxies
• Chandra and XMM Observations of Type II Quasars from the SDSS
• A Medium Survey of the Hard X-Ray Sky with ASCA. II.: The Source's Broad Band X-Ray Spectral Properties
• Searching for mid-IR obscured AGN in the CDF-N
• NGC3147: a "true" Seyfert 2 without the broad-line region
• The distribution of absorption in AGN detected in the XMM-Newton observations of the CDFS
• The redshift evolution of major merger triggering of luminous AGN: a slight enhancement at z$\sim$2
• The properties of the AGN torus as revealed from a set of unbiased NuSTAR observations
• Discovery of a nuclear gas bar feeding the active nucleus in Circinus
• Polycyclic Aromatic Hydrocarbons in Seyfert and star-forming galaxies
• Spectropolarimetry of a Complete Infrared Selected Sample of Seyfert 2 Galaxies
• Chandra Observations of Nuclear X-ray Emission from a Sample of Radio Sources
• Unveiling the nature of the highly obscured AGN in NGC5643 with XMM-Newton
• Compact Nuclear Starbursts in Seyfert 2 Galaxies from the CfA and 12 Micron Samples
• The MicroJansky Radio Galaxy Population
• The Unified model and the Seyfert 2 infrared dichotomy
• Silicate absorption in heavily obscured galaxy nuclei
• Excess Hard X-ray Emission from the Obscured Low Luminosity AGN In the Nearby Galaxy M 51 (NGC 5194)
• Compton Thick AGN in the 70 Month Swift-BAT All-Sky Hard X-ray Survey: a Bayesian approach
• Compton-thick AGN in the NuSTAR era III: A systematic study of the torus covering factor
• Suzaku observations of hard X-ray selected Seyfert 2 galaxies
• Balancing the Cosmic Energy Budget: The Cosmic X-ray Background, Blazars and the Compton Thick AGN Fraction
• Unabsorbed Seyfert 2 galaxies: the case of "naked" AGN
• Piercing Through Highly Obscured and Compton-thick AGNs in the Chandra Deep Fields: I. X-ray Spectral and Long-term Variability Analyses
• Evidence for a large fraction of Compton-thick quasars at high redshift
• Heavily Obscured AGN in High Redshift Luminous Infrared Galaxies
• Determining the torus covering factors for a sample of type 1 AGN in the local Universe
• Does the AGN Unified Model Evolve with Redshift? Utilizing the X-ray Background to Predict the Mid-Infrared Emission of AGN
• Infrared spectroscopy around 4micron of Seyfert 2 galaxies: Obscured broad line regions and coronal lines
• The HST view of the nuclear emission line region in low luminosity radio-galaxies
• X-Ray Evolution of Active Galactic Nuclei and Hierarchical Galaxy Formation
• The Chandra X-ray point source catalog in the DEEP2 Galaxy Redshift Survey fields
• Obscured and unobscured AGN populations in a hard-X-ray selected sample of the XMDS survey
• Geometrically thick obscuration by radiation-driven outflow from magnetized tori of active galactic nuclei
• The broad-band XMM-Newton and INTEGRAL spectra of bright type 1 Seyfert galaxies
• Deep Chandra Observations of ESO 428-G014: II. Spectral Properties and Morphology of the Large-Scale Extended X-ray Emission
• X-ray Constraints on the AGN Properties in Spitzer-IRS identified z~2 Ultraluminous Infrared Galaxies
• H1320+551: A Seyfert 1.8/1.9 galaxy with an unabsorbed X-ray spectrum
• X-ray constraints on the fraction of obscured AGN at high accretion luminosities
• The intrinsic emission of Seyfert galaxies observed with BeppoSAX/PDS I. Comparison of the average spectra of the three classes of Seyfert Galaxies
• Determining Inclinations of Active Galactic Nuclei Via Their Narrow-Line Region Kinematics - II. Correlation With Observed Properties
• Gas Dynamics in the LINER Galaxy NGC 5005: Episodic Fueling of a Nuclear Disk
• Deconstructing NGC 7130
• Constraints on light bending and reflection from the hard X-ray background
• The Ly-edge paradox and the need for obscured QSOs
• Ionized Gas Outflows from the MAGNUM Survey: NGC 1365 and NGC 4945
• BAT AGN Spectroscopic Survey XXVII: Scattered X-Ray Radiation in Obscured Active Galactic Nuclei
• BAT AGN Spectroscopic Survey--VIII. Type 1 AGN With Massive Absorbing Columns
• X-ray spectral properties of Seyfert galaxies and the unification scheme
• The AGN nature of 11 out of 12 Swift/RXTE unidentified sources through optical and X-ray spectroscopy
• Disclosing the true nature of the Sy 2 galaxy NGC 3281: one more Compton-thick source
• Physics of Coevolution of Galaxies and Supermassive Black Holes
• A strong excess in the 20-100 keV emission of NGC 1365
• A New Compton-thick AGN in our Cosmic Backyard: Unveiling the Buried Nucleus in NGC 1448 with NuSTAR
• The infrared luminosity of the torus and the visibility of scattered broad line emission in Seyfert 2 galaxies
• Accretion and Outflow in the AGN and Starburst of NGC 5135
• A deep INTEGRAL hard X-ray survey of the 3C 273/Coma region
• Obscured AGN: the hidden side of the X-ray Universe
• Highlights and Discoveries from the Chandra X-ray Observatory
• Compton-Thick X-ray Absorption in the Seyfert Galaxies Tololo 0109-383 and ESO 138-G1
• The circumnuclear X-ray reflectors in NGC 1068 and the Circinus Galaxy
• XMM-NEWTON Observations of Red AGN
• The cosmological consequence of an obscured AGN population on the radiation efficiency
• On the nuclear obscuration of H2O maser galaxies
• A hard look at local, optically-selected, obscured Seyfert galaxies
• About AGN ionization echoes, thermal echoes, and ionization deficits in low redshift Lyman-alpha blobs
• Chandra and Spitzer observations of CDFS X-ray obscured QSOs
• X-ray versus Optical Observations of Active Galactic Nuclei: Evidence for Large Grains?
• On the nature of X-ray absorption in Seyfert 2 galaxies
• The X-ray background and the deep X-ray surveys
• The Origin of Double-Peaked Narrow Lines in Active Galactic Nuclei III: Feedback from Biconical AGN Outflows
• X-ray emission from the nuclear region of Arp 220
• The demographics of obscured AGN from X-ray spectroscopy guided by multiwavelength information
• The column density distribution of hard X-ray radio galaxies
• Radiation pressure, absorption and AGN feedback in the Chandra Deep Fields
• Nuclear obscuration and scattering in Seyfert 2 galaxies
• CO excitation in the Seyfert galaxy NGC7130
• X-ray Emission from Megamaser Galaxy IC 2560
• An Iwasawa-Taniguchi Effect for Compton-thick Active Galactic Nuclei
• The Different Nature in Seyfert 2 Galaxies With and Without Hidden Broad-Line Regions
• IC 3639 - A new bona fide Compton thick AGN unveiled by NuSTAR
• The Deep Chandra Survey of the Groth Strip - II. optical identification of the X-ray sources
• Eddington ratio and accretion efficiency in AGN evolution
• X-ray observations of highly obscured 9.7 micron sources: an efficient method for selecting Compton-thick AGN ?
• Active Galactic Nucleus Pairs from the Sloan Digital Sky Survey. III. Chandra X-ray Observations Unveil Obscured Double Nuclei
• Tracing the Nuclear Accretion History of the Red Galaxy Population
• $NuSTAR$ Observations of Four Nearby X-ray Faint AGN: Low Luminosity or Heavy Obscuration?
• NuSTAR Observations of AGN with Low Observed X-ray to [OIII] Luminosity Ratios: Heavily Obscured AGN or Turned-Off AGN?
• Radiation Pressure Supported AGN Tori with Hard X-Ray and Stellar Heating
• Compton-thick AGN in the NuSTAR era II: A deep NuSTAR and XMM-Newton view of the candidate Compton thick AGN in NGC 1358
• AGN Triality of Triple Mergers: Detection of Faint X-ray Point Sources
• Measuring the level of nuclear activity in Seyfert galaxies and the unification scheme
• A model for the X-ray absorption in Compton--thin AGN
• Deep Chandra Observations of ESO 428-G014: IV. The Morphology of the Nuclear Region in the Hard Continuum and Fe Kα Line
• A comparison between the soft X-ray and [O III] morphologies of active galactic nuclei
• On the Contribution of AGN to the Cosmic Background Radiation
• X-ray spectral properties of seven heavily obscured Seyfert 2 galaxies
• Where are Compton-thick radio galaxies? A hard X-ray view of three candidates
• Extended X-ray Emission in Compton Thick AGN with Deep Chandra Observations
• X-ray properties of Lyman Break Galaxies in the Hubble Deep Field North region
• Constraining the X-ray reflection in low accretion rate AGN using XMM-Newton, NuSTAR and Swift
• One-zone models for spheroidal galaxies with a central supermassive black-hole. Self-regulated Bondi accretion
• An X-ray view of the active nucleus in NGC 4258
• The Cosmic History of Black Hole Growth from Deep Multiwavelength Surveys
• Photon Bubbles in the Circumstellar Envelopes of Young Massive Stars
• The 9 and 18 Micron Luminosity Function of Various Types of Galaxies with AKARI: Implication for the Dust Torus Structure of AGN
• The neutrino background from non-jetted active galactic nuclei
• Compton-thick AGN in the NuSTAR era IV: A deep NuSTAR and XMM-Newton view of the candidate Compton thick AGN in ESO 116-G018
• BH Accretion in Low-Mass Galaxies Since z~1
• The Cosmological History of Accretion onto Dark Halos and Supermassive Black Holes
• INTEGRAL view of AGN
• XMM-Newton Observations of the Narrow-Line Seyfert 1 Galaxy IRAS 13224$-$3809 : X-ray Spectral Analysis II
• The contribution of Quasars to the Far Infrared Background
• A Joint Model of the X-ray And Infrared Extragalactic Backgrounds: I. Model Construction And First Results
• From Thin to Thick: The Impact of X-ray Irradiation on Accretion Disks in AGN
• Active galactic nuclei synapses: X-ray versus optical classifications using artificial neural networks
• RXTE View of the Starburst Galaxies M82 and NGC 253
• The X-ray variability of Seyfert 1.8/1.9 galaxies
• The Spectral Energy Distributions of Red 2MASS AGN
• Inferring the morphology of AGN torus using X-ray spectra: A reliability study
• Constraints on the distribution of absorption in the X-ray selected AGN population found in the 13H XMM-Newton/Chandra deep field
• Beyond Simple AGN Unification with Chandra-observed 3CRR Sources
• Chandra Detection of the Circumnuclear Molecular Torus of the Compton Thick AGN in NGC 5643
• A new sample of X-ray selected narrow emission-line galaxies. II. Looking for True Seyfert 2
• Unveiling the Fast Acceleration of AGN-Driven Winds at Kiloparsec Scales
• Nuclear Infrared Spectral Energy Distribution of Type II Active Galactic Nuclei
• A Chandra observation of the H2O megamaser IC2560
• A hard look at NGC 5347: revealing a nearby Compton-thick AGN
• Reflection-dominated nuclear X-ray emission in the early-type galaxy ESO 565--G019
• X-ray spectroscopy of the Compton-thick Seyfert 2 ESO 138-G1
• Formation of Obscuring Walls by Radiation Force from Circumnuclear Starbursts and Implications for Starburst-Active Galactic Nucleus Connection
• Optical-NIR spectroscopy of the puzzling gamma-ray source 3FGL 1603.9-4903/PMN J1603-4904 with X-shooter
• New X-ray Constraints on Starburst and Seyfert Activity in the Barred Spiral Galaxy NGC 1672
• A candidate relativistic tidal disruption event at 340 Mpc
• Active galactic nuclei ghosts: A systematic search for faded nuclei
• Nuclear obscuration in the high-ionization Seyfert 2 galaxy Tol 0109-383
• X-ray spectroscopy in the microcalorimeter era II: A new Diagnostic on Column Density from the Case A to B Transition in H- and He-like Iron
• X-ray observations of the Ultraluminous infrared galaxy IRAS19254-7245 (The Superantennae)
• Near-infrared spectroscopy of nearby Seyfert galaxies: Is there evidence for the shock excitation in narrow-line regions?
• Are SMBHs shrouded by "super-Oort" clouds of comets and asteroids?
• The nuclear dust lane of Circinus: collimation without a torus
• 22 GHz Water Maser Search in 37 Nearby Galaxies - Four New Water Megamasers in Seyfert 2 and OH Maser/Absorber Galaxies
• Obscuration of Active Galactic Nuclei by Circumnuclear Starbursts
• Slicing the Torus: Obscuring Structures in Quasars
• Detection of type-2 quasars in the radio galaxies B3 0731+438 and 3C 257
• Investigating the central engine of Seyfert 2 galaxies with and without Polarized Broad Lines
• A Joint Model Of X-ray And Infrared Backgrounds. II. Compton-Thick AGN Abundance
• Circumnuclear obscuration of the Circinus galaxy by a starburst-radiation supported wall
• HI and CO observations of Arp 104: a spiral-elliptical interacting pair
• No evidence for excess AGN activity in recently quenched massive galaxies at cosmic noon
• An Unobscured type II quasar candidate: SDSS J012032.19-005501.9
• Hidden AGNs in Early-Type Galaxies
• Unsupervised Machine Learning for the Classification of Astrophysical X-ray Sources
• ALMA observations of the submillimetre hydrogen recombination line from the type 2 active nucleus of NGC 1068
• A Model for Type 2 Coronal Line Forest (CLiF) AGN
• Clumpy winds and the obscuration of Active Galactic Nuclei
• Chandra Reveals Heavy Obscuration and Circumnuclear Star Formation in Seyfert 2 Galaxy NGC 4968
• A unique X-ray unabsorbed Seyfert 2 galaxy IRAS F01475-0740
• Evolution of luminosity function and obscuration of AGN: connecting X-ray and Infrared
• Rolling down from the 30 keV peak: modelling the hard X-ray and gamma-ray backgrounds
• Comparing Chandra and SIRTF Observations for Obscured Starbursts and AGN at High Redshift
• On the Evolution of High-Redshift Active Galactic Nuclei
• X-ray Spectroscopy and Variability of AGN Detected in the 2 Ms Chandra Deep Field-North Survey
• The interaction of the active nucleus with the host galaxy interstellar medium
• Isolated AGNs NGC 5347, ESO 438-009, MCG-02-04-090, and J11366-6002: Swift and NuSTAR joined view
• XMM Observations of the Seyfert 2 Galaxy NGC 7590: the Nature of X-ray Absorption
• XMM Follow-Up Observations of Three Swift BAT-Selected Active Galactic Nuclei
• Suzaku X-ray spectral study of the Compton-thick Seyfert galaxy NGC 5135
• Characterization of AGN and their hosts in the Extended Groth Strip: a multiwavelength analysis
• AGN Triality of Triple Mergers: Multi-wavelength Classifications
• Are Seyfert 2 Galaxies without Polarized Broad Emission Lines More Obscured?
• MIRACLE I.: Unveiling the Multi-Phase, Multi-Scale physical properties of the Active Galaxy NGC 424 with MIRI, MUSE, and ALMA
• A candidate Optically Quiescent Quasar lacking narrow emission lines
• The study of Seyfert 2 galaxies with and without infrared broad lines
• The XMM spectral catalog of SDSS optically selected Seyfert 2 galaxies
• Probing the roles of orientation and multi-scale gas distributions in shaping the obscuration of Active Galactic Nuclei through cosmic time
• The Young, the Old, and the Dusty: Stellar Populations of AGN Hosts
• Evolution of supermassive black holes
• Classical radio source propagating into outer HI disc in NGC 3801
• The Awakening Beast in the Seyfert 1 Galaxy KUG 1141+371 I
• On the fate of the matter reinserted within young nuclear stellar clusters
• Analysis of the Interaction Effects in the Southern Galaxy Pair Tol1238-364 and ESO381-G009
• Inferring Compton-thick AGN candidates at z>2 with Chandra using the >8 keV restframe spectral curvature
• X-ray Eclipses of Active Galactic Nuclei
• Detecting quasars at very high redshift with next generation X-ray telescopes
• X-ray Survey Results on Active Galaxy Physics and Evolution
• Searching for obscured AGN in z $\sim$ 2 submillimetre galaxies
• The luminous infrared composite Seyfert 2 galaxy NGC 7679 through the [O III] 5007 emission line
• A Statistical Study of H I Gas in Nearby Narrow-Line AGN-Hosting Galaxies
• X-ray view of four high-luminosity Swift/BAT AGN: Unveiling obscuration and reflection with Suzaku
• Distant X-ray Galaxies: Insights from the Local Population
• The hard X-ray view of bright infrared galaxies
• Active Galactic Nuclei and their demography through cosmic time
• Multiwavelength Analysis of a Nearby Heavily Obscured AGN in NGC 449
• XMMU J134736.6+173403: an eclipsing LMXB in quiescence or a peculiar AGN?
• X-ray selection of Compton Thick AGN at high redshift
• VLBI Detection of an Active Radio Source Potentially Driving 100-kpc Scale Emission in the Ultraluminous Infrared Galaxy IRAS F01004$-$2237
• An excess of low-mass X-ray binaries in the outer halo of NGC 4472
• The X-ray Nature of Nucleus in Seyfert 2 Galaxy NGC 7590
• Characterisation of AGN from the XMM-Newton Slew Survey
• The XMM-SSC survey of hard-spectrum XMM-Newton sources 1: optically bright sources
• A new panchromatic classification of unclassified Burst Alert Telescope active galactic nuclei
• On the origin of the X-ray emission from a narrow-line radioquasar at z>1
• Supermassive Black Holes in Deep Multiwavelength Surveys
• Aspects of astrophysical particle production and beyond the Standard Model phenomenology
• The $N_H$ Distribution of Hard X-ray Selected AGN in the NEP Field
• The XMM-Newton hard band wide angle Survey
• MIDIS: Quantifying the AGN component of X-ray-detected galaxies
• A multiwavelength study of near- and mid-infrared selected galaxies at high redshift: ERGs, AGN-identification and the contribution from dust
• X-ray properties of two complementary samples of intermediate Seyfert galaxies
• Optical Variability Structure Function of Low-Luminosity AGN using ATLAS Lightcurves
• Chandra Follow-up Observations of Swift-BAT-selected AGNs II