Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. XIV. Long-Duration High-Cadence Reverberation Mapping Results for 11 PG Quasars

Abstract

We report the results of a long-duration high-cadence reverberation mapping campaign of a second batch of 11 PG quasars using the 2.2m telescope at the Calar Alto Observatory. This follows a similar earlier study of another sample of 15 objects reported by Hu et al. (2021). Among the 11 PG quasars, 8 objects have the H${\hat{I}}^2$ time lags measured for the first time, while the other 3 objects were observed in previous campaigns, but only had highly uncertain H${\hat{I}}^2$-lag measurements. Long-term light curves are presented of photometric $V$-band, spectroscopic 5100 Ã continuum, and the H${\hat{I}}^2$ emission line, lasting for $\sim$3--6 years with a cadence of $\sim$6--14 days. Accurate H${\hat{I}}^2$ time lags ranging from $\sim$20 to 150 days in the rest frame are obtained. The estimated virial masses of the central supermassive black holes range from $\sim$(3--300)$\times 10^7{M}_{\odot }$. Combining these results with those reported in Hu et al. (2021), we now have 26 PG quasars, with representative properties, having reliable H${\hat{I}}^2$ time-lag measurements from our long-duration high-cadence campaign. A tentative fit to the relation between the H${\hat{I}}^2$ time lag and the continuum luminosity for these 26 objects gives a slope of 0.53.

20 pages, 17 figures, accepted for publication in ApJS