Monitoring AGNs with H$\beta$ Asymmetry. III. Long-term Reverberation Mapping Results of 15 Palomar-Green Quasars

TL;DR

This study presents long-term reverberation mapping results for 15 PG quasars, revealing diverse BLR geometries and kinematics, and providing new insights into black hole mass estimates and AGN structure over several years.

Contribution

First long-term reverberation mapping campaign for 15 PG quasars, including new measurements and analysis of BLR geometry and kinematics over multiple years.

Findings

Diverse BLR geometries and kinematics observed.

Keplerian/virialized motion and inflow are more common than outflow.

Black hole masses estimated from Hβ time lags.

Abstract

In this third paper of the series reporting on the reverberation mapping (RM) campaign of active galactic nuclei with asymmetric H$\beta$ emission-line profiles, we present results for 15 Palomar-Green (PG) quasars using spectra obtained between the end of 2016 to May 2021. This campaign combines long time spans with relatively high cadence. For 8 objects, both the time lags obtained from the entire light curves and the measurements from individual observing seasons are provided. Reverberation mapping of 9 of our targets has been attempted for the first time, while the results for 6 others can be compared with previous campaigns. We measure the H$\beta$ time lags over periods of years and estimate their black hole masses. The long duration of the campaign enables us to investigate their broad line region (BLR) geometry and kinematics for different years by using velocity-resolved lags, which demonstrate signatures of diverse BLR geometry and kinematics. The BLR geometry and kinematics of individual objects are discussed. In this sample, the BLR kinematics of Keplerian/virialized motion and inflow is more common than outflow.