BASS XXV: DR2 Broad-line Based Black Hole Mass Estimates and Biases from Obscuration

Abstract

We present measurements of broad emission lines and virial estimates of supermassive black hole masses ($M_{BH}$) for a large sample of ultra-hard X-ray selected active galactic nuclei (AGNs) as part of the second data release of the BAT AGN Spectroscopic Survey (BASS/DR2). Our catalog includes $M_{BH}$ estimates for a total 689 AGNs, determined from the H$\alpha$, H$\beta$, $MgII\lambda 2798$, and/or $CIV\lambda 1549$ broad emission lines. The core sample includes a total of 512 AGNs drawn from the 70-month Swift/BAT all-sky catalog. We also provide measurements for 177 additional AGNs that are drawn from deeper Swift/BAT survey data. We study the links between $M_{BH}$ estimates and line-of-sight obscuration measured from X-ray spectral analysis. We find that broad H$\alpha$ emission lines in obscured AGNs ($\log (N_{\mathrm{H}}/{\mathrm{cm}}^{-2})>22.0$) are on average a factor of $8.0_{-2.4}^{+4.1}$ weaker, relative to ultra-hard X-ray emission, and about $35_{-12}^{+7}$\% narrower than in unobscured sources (i.e., $\log (N_{\mathrm{H}}/{\mathrm{cm}}^{-2})<21.5$). This indicates that the innermost part of the broad-line region is preferentially absorbed. Consequently, current single-epoch $M_{BH}$ prescriptions result in severely underestimated ($>$1 dex) masses for Type 1.9 sources (AGNs with broad H$\alpha$ but no broad H$\beta$) and/or sources with $\log (N_{\mathrm{H}}/{\mathrm{cm}}^{-2})>22.0$. We provide simple multiplicative corrections for the observed luminosity and width of the broad H$\alpha$ component ($L[\mathrm{b}\mathrm{H}\alpha ]$ and FWHM[bH$\alpha$]) in such sources to account for this effect, and to (partially) remedy $M_{BH}$ estimates for Type 1.9 objects. As key ingredient of BASS/DR2, our work provides the community with the data needed to further study powerful AGNs in the low-redshift Universe.

published in ApJS

References in corpus (53)

• Array Programming with NumPy
• Molecfit: A general tool for telluric absorption correction. I. Method and application to ESO instruments
• BAT AGN Spectroscopic Survey - V. X-ray properties of the Swift/BAT 70-month AGN catalog
• Biases in Virial Black Hole Masses: An SDSS Perspective
• The diversity of quasars unified by accretion and orientation
• The AGN Black Hole Mass Database
• The close environments of accreting massive black holes are shaped by radiative feedback
• BAT AGN Spectroscopic Survey I: Spectral Measurements, Derived Quantities, and AGN Demographics
• Physical properties of 15 quasars at $z\gtrsim 6.5$
• The dark nemesis of galaxy formation: why hot haloes trigger black hole growth and bring star formation to an end
• Dust covering factor, silicate emission and star formation in luminous QSOs
• Black Holes on FIRE: Stellar Feedback Limits Early Feeding of Galactic Nuclei
• The black hole mass - stellar velocity dispersion relation of narrow-line Seyfert 1 galaxies
• A 0.8-2.4 microns spectral atlas of Active Galactic Nuclei
• Broad-line Balmer Decrements in Blue Active Galactic Nuclei
• Correcting CIV-Based Virial Black Hole Masses
• Stellar kinematics across the Hubble sequence in the CALIFA survey: General properties and aperture corrections
• BASS XXII: The BASS DR2 AGN Catalog and Data
• The X-Ray to Mid-Infrared Relation of AGN at High Luminosity
• Modeling reverberation mapping data I: improved geometric and dynamical models and comparison with cross-correlation results
• No significant evolution of relations between Black hole mass and Galaxy total stellar mass up to z~2.5
• A New Catalogue of Type 1 AGN and its Implication on the AGN Unified Model
• Optical variability of AGN in the PTF/iPTF survey
• The effect of nuclear gas distribution on the mass determination of supermassive black holes
• The cosmic growth of the active black hole population at 1<z<2 in zCOSMOS, VVDS and SDSS
• Double-peaked profiles: ubiquitous signatures of disks in the Broad Emission Lines of Active Galactic Nuclei
• The Complete Infrared View of Active Galactic Nuclei from the 70-month Swift/BAT Catalog
• Radiation pressure and absorption in AGN: results from a complete unbiased sample from Swift
• BAT AGN Spectroscopic Survey - IV: Near-Infrared Coronal Lines, Hidden Broad Lines, and Correlation with Hard X-ray Emission
• Galaxy gas as obscurer: II. Separating the galaxy-scale and nuclear obscurers of Active Galactic Nuclei
• Black hole scaling relations of active and quiescent galaxies: Addressing selection effects and constraining virial factors
• The M_BH - M_star relation for X-ray obscured, red QSOs at 1.2< z <2.6
• BAT AGN Spectroscopic Survey-XX: Molecular Gas in Nearby Hard X-ray Selected AGN Galaxies
• Spectral Properties From Lyman-alpha to H-alpha For An Essentially Complete Sample of Quasars I: Data
• Virial Black Hole Mass Estimates for 280,000 AGNs from the SDSS Broad-Band Photometry and Single Epoch Spectra
• BAT AGN Spectroscopic Survey XXI: The Data Release 2 Overview
• BASS XXIV: The BASS DR2 Spectroscopic Line Measurements and AGN Demographics
• LLAMA: The $M_{BH}$ - ${\sigma }_{\star }$ Relation of the most luminous local AGNs
• Black hole mass estimation for Active Galactic Nuclei from a new angle
• The NuSTAR Serendipitous Survey: Hunting for The Most Extreme Obscured AGN at >10 keV
• The structure of the Mg II broad line emitting region in Type 1 AGNs
• BASS XXVI: DR2 Host Galaxy Stellar Velocity Dispersions
• SUPER III. Broad Line Region properties of AGN at z$\sim$2
• BAT AGN Spectroscopic Survey -- XIX: Type 1 versus Type 2 AGN dichotomy from the point of view of ionized outflows
• BASS XXIX: The near-infrared view of the BLR: the effects of obscuration in BLR characterisation
• Novel calibrations of virial black hole mass estimators in active galaxies based on X-ray luminosity and optical/NIR emission lines
• Compaction-Driven Black Hole Growth
• BASS XXVIII: Near-infrared Data Release 2, High-Ionization and Broad Lines in Active Galactic Nuclei
• Detection of faint broad emission lines in type 2 AGN: I. Near infrared observations and spectral fitting
• Detection of faint broad emission lines in type 2 AGN: III. On the $M_{BH}-{\sigma }_{\star }$ relation of type 2 AGN
• Medium-resolution Optical and Near-Infrared Spectral Atlas of 16 2MASS-selected NIR-red Active Galactic Nuclei at $z\sim 0.3$
• UV spectral diagnostics for low redshift quasars: estimating physical conditions and radius of the Broad Line Region
• Detection of a double-peaked H$\alpha$ component from the accretion disc of NGC 4958

Cited by in corpus (30)

• BASS XXII: The BASS DR2 AGN Catalog and Data
• BAT AGN Spectroscopic Survey XXI: The Data Release 2 Overview
• BASS XXIV: The BASS DR2 Spectroscopic Line Measurements and AGN Demographics
• BASS XXXVII: The role of radiative feedback in the growth and obscuration properties of nearby supermassive black holes
• BASS XXVI: DR2 Host Galaxy Stellar Velocity Dispersions
• A Tight Correlation Between Millimeter and X-ray Emission in Accreting Massive Black Holes from <100 Milliarcsecond-resolution ALMA Observations
• Exploring Changing-look Active Galactic Nuclei with the Sloan Digital Sky Survey V: First Year Results
• BASS XXXIX: Swift-BAT AGN with changing-look optical spectra
• A Transient "Changing-look'' Active Galactic Nucleus Resolved on Month Timescales from First-year Sloan Digital Sky Survey V Data
• BASS XXIX: The near-infrared view of the BLR: the effects of obscuration in BLR characterisation
• BASS XXVIII: Near-infrared Data Release 2, High-Ionization and Broad Lines in Active Galactic Nuclei
• Probing the Structure and Evolution of BASS AGN through Eddington Ratios
• AT 2021loi: A Bowen Fluorescence Flare with a Rebrightening Episode, Occurring in a Previously-Known AGN
• Investigating Changing-Look Active Galactic Nuclei with Long-term Optical and X-Ray Observations
• BASS. XXXVI. Constraining the Local Supermassive Black Hole - Halo Connection with BASS DR2 AGN
• JWST ERS Program Q3D: The pitfalls of virial BH mass constraints shown in a z = 3 quasar with an ultramassive host
• BASS-XL: X-ray variability properties of unobscured Active Galactic Nuclei
• Quasars as standard candles VI: spectroscopic validation of the cosmological sample
• Lack of Correlations between Cold Molecular Gas and AGN Properties in Type 1 AGNs at $z\lesssim 0.5$
• Millimeter emission from supermassive black hole coronae
• Updated Picture of the Active Galactic Nuclei with Dusty/Dust-free Gas Structures and Effects of the Radiation Pressure
• Extinction and AGN over host galaxy contrast effects on the optical spectroscopic classification of AGN
• BASS XLV: Quantifying AGN Selection Effects in the Chandra COSMOS-Legacy Survey with BASS
• The X-ray weakness of Little Red Dots and JWST-selected AGN: comparison with local AGN in different accretion regimes
• Searching for supermassive black holes binaries within SRG/eROSITA-De I: Properties of the X-ray selected candidates
• BASS. XLIV. Morphological preferences of local hard X-ray selected AGN
• AGN with massive black holes have closer galactic neighbors: k-Nearest-Neighbor statistics of an unbiased sample of AGN at z~0.03
• Galaxy and black hole coevolution in dark matter haloes not captured by cosmological simulations
• BASS XXX: Distribution Functions of DR2 Eddington-ratios, Black Hole Masses, and X-ray Luminosities
• Measuring monster MBHs: maybe mighty, maybe merely massive