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-Hβ 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 Hβ-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 10 (M BH ) = 7.25 −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 log 10f = 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 M BH -σ 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.

Modelling the AGN broad-line region using single-epoch spectra − II. Nearby AGNs

“…The first 4 objects from the top are part of the AGN10 monitoring campaign while the remaining 7 objects are from LAMP 2011. The filled blue circles are the inferred values using the single-epoch analysis while the black star symbols are the inferred values found by previous work using the full light-curve for the modelling of the BLR (Grier et al 2017for AGN10 and Williams et al 2018for LAMP 2011. The values inferred by Williams et al 2018 refer to their combined posterior probability distribution.…”

“…In previous versions of the model, the generated continuum light curve was constrained based on the observed continuum light curve as determined from monitoring campaigns (e.g. Pancoast et al 2014b, Grier et al 2017, Pancoast et al 2018, Williams et al 2018. In our version of the model, where we use only a single spectrum instead of monitoring data, we do not have an observed light curve to analyse (R19).…”

“…We select a sample of 11 AGN: 4 AGN from the AGN10 monitoring campaign (Grier et al 2012, Grier et al 2017 and 7 AGN from the Lick AGN Monitoring Project 2011 (LAMP 2011; Barth et al 2015 Pancoast et al (2018) and the full monitoring dataset. This allows for a direct comparison with our results.…”

“…Our approach will be referred to as singleepoch modelling, as we use a single spectrum to constrain the model parameters. The BLR parameters inferred from the full light-curve modelling are presented by Grier et al (2017) and Williams et al (2018) and will be used as a comparison to our modelling results using single-epoch spectra. We use the same original datasets as Grier et al (2017) and Williams et al (2018) as a starting point, including the same spectral decompositions.…”

A geometric probe of cosmology – I. Gravitational lensing time delays and quasar reverberation mapping

“…The BLR may be approximated by a flat geometry in Keplerian orbit around a central black hole, e.g. Grier et al (2017). As a toy example of reverberation mapping, we therefore consider an infinitesimally thin BLR ring, at the same redshift as the central source, facing the observer plane with a constant linear number density.…”