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arXiv · 1705.02346

The Structure of the Broad-Line Region In Active Galactic Nuclei. II. Dynamical Modeling of Data from the AGN10 Reverberation Mapping Campaign

Abstract

We present inferences on the geometry and kinematics of the broad-Hbeta line-emitting region in four active galactic nuclei monitored as a part of the fall 2010 reverberation mapping campaign at MDM Observatory led by the Ohio State University. From modeling the continuum variability and response in emission-line profile changes as a function of time, we infer the geometry of the Hbeta- emitting broad line regions to be thick disks that are close to face-on to the observer with kinematics that are well-described by either elliptical orbits or inflowing gas. We measure the black hole mass to be log (MBH) = 7.25 (+/-0.10) for Mrk 335, 7.86 (+0.20, -0.17) for Mrk 1501, 7.84 (+0.14, -0.19) for 3C 120, and 6.92 (+0.24, -0.23) for PG 2130+099. These black hole mass measurements are not based on a particular assumed value of the virial scale factor f, allowing us to compute individual f factors for each target. Our results nearly double the number of targets that have been modeled in this manner, and investigate the properties of a more diverse sample by including previously modeled objects. We measure an average scale factor f in the entire sample to be log10(f) = 0.54 +/- 0.17 when the line dispersion is used to characterize the line width, which is consistent with values derived using the normalization of the MBH-sigma relation. We find that the scale factor f for individual targets is likely correlated with the black hole mass, inclination angle, and opening angle of the broad line region but we do not find any correlation with the luminosity.

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BibTeXRIS

C. J. Grier, A. Pancoast, A. J. Barth, M. M. Fausnaugh, B. J. Brewer, T. Treu, B. M. Peterson. 2017-09-27. The Structure of the Broad-Line Region In Active Galactic Nuclei. II. Dynamical Modeling of Data from the AGN10 Reverberation Mapping Campaign. https://doi.org/10.3847/1538-4357%2Faa901b

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