Abstract We have modeled the velocity-resolved reverberation response of the H β broad emission line in nine Seyfert 1 galaxies from the Lick Active Galactic Nucleus (AGN) Monitoring Project 2016 sample, drawing inferences on the geometry and structure of the low-ionization broad-line region (BLR) and the mass of the central supermassive black hole. Overall, we find that the H β BLR is generally a thick disk viewed at low to moderate inclination angles. We combine our sample with prior studies and investigate line-profile shape dependence, such as log 10 ( FWHM / σ ) , on BLR structure and kinematics and search for any BLR luminosity-dependent trends. We find marginal evidence for an anticorrelation between the profile shape of the broad H β emission line and the Eddington ratio, when using the rms spectrum. However, we do not find any luminosity-dependent trends, and conclude that AGNs have diverse BLR structure and kinematics, consistent with the hypothesis of transient AGN/BLR conditions rather than systematic trends.
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What Does the Geometry of the Hβ BLR Depend On?
Abstract We combine our dynamical modeling black-hole mass measurements from the Lick AGN Monitoring Project 2016 sample with measured cross-correlation time lags and line widths to recover individual scale factors, f , used in traditional reverberation-mapping analyses. We extend our sample by including prior results from Code for AGN Reverberation and Modeling of Emission Lines ( caramel ) studies that have utilized our methods. Aiming to improve the precision of black-hole mass estimates, as well as uncover any regularities in the behavior of the broad-line region (BLR), we search for correlations between f and other AGN/BLR parameters. We find (i) evidence for a correlation between the virial coefficient log 10 ( f mean , σ ) and black-hole mass, (ii) marginal evidence for a similar correlation between log 10 ( f rms , σ ) and black-hole mass, (iii) marginal evidence for an anticorrelation of BLR disk thickness with log 10 ( f mean , FWHM ) and log 10 ( f rms , FWHM ) , and (iv) marginal evidence for an anticorrelation of inclination angle with log 10 ( f mean , FWHM ) , log 10 ( f rms , σ ) , and log 10 ( f mean , σ ) . Last, we find marginal evidence for a correlation between line-profile shape, when using the root-mean-square spectrum, log 10 ( FWHM / σ ) rms , and the virial coefficient, log 10 ( f rms , σ ) , and investigate how BLR properties might be related to line-profile shape using caramel models.
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- PAR ID:
- 10415542
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 948
- Issue:
- 2
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 95
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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