Active Galactic Nuclei with Ultrafast Outflows Monitoring Project: The Broad-line Region of Mrk 79 as a Disk Wind

We developed a spectroscopic monitoring project to investigate the kinematics of the broad-line region (BLR) in active galactic nuclei (AGNs) with ultrafast outflows (UFOs). Mrk 79 is a radio-quiet AGN with UFOs and warm absorbers and has been monitored by three reverberation mapping (RM) campaigns, but its BLR kinematics are not yet understood. In this paper, we report the results from a new RM campaign of Mrk.79, which was undertaken with the Lijiang 2.4 m telescope. Mrk.79 appears to come out the faint state, with the mean flux approximately a magnitude fainter than the historical record. We successfully measured the lags of the broad emission lines including H beta lambda 4861, H gamma lambda 4340, He II lambda 4686, and He. I lambda 5876 with respect to the varying AGN continuum. Based on the broad H beta lambda 4861 line, we measured a black hole mass of M. = 5.13(-1.55)(+1.57) x 10(7) M-circle dot and an estimated accretion rate of (M)over dot. = (0.05 +/- 0.02) L-Edd c(-2), indicating that Mrk.79 is a sub-Eddington accretor. We found that Mrk 79 deviates from the canonical Radius-Luminosity relationship. The marginal blueshift of the broad He II lambda 4686 line detected from the rms spectrum indicates outflow of high-ionization gas. The velocity-resolved lag profiles of the broad H gamma lambda 4340, H beta lambda 4861, and He I lambda 5876 lines show similar signatures such that the largest lag occurs in the red wing of the lines and then the lag decreases to both sides. These signatures may suggest that the BLR of Keplerian motion probably exists as outflow gas motion. All findings including UFOs, warm absorbers, and the kinematics of high- and low-ionization BLR, may provide indirect evidence that the BLR of Mrk 79 probably originates from a disk wind.