Ultra-efficient photometric Reverberation Mapping of high-z AGN with IO:O

The ability to accurately measure black hole masses is key to characterising the effect of AGN upon their host galaxies. A number of techniques have been developed to measure masses of AGN, but none are as direct and precise as reverberation mapping.
Reverberation mapping relies upon the assumption that hard continuum emission from the central black hole’s accretion disk directly influences the emission of the broad-line gas clouds surrounding it. Variation in the continuum emission should therefore be visible in the broad-line emission time-series. Thus, the radius of the broad-line region can be inferred from the lag between the two emission time-series.
However, reverberation mapping is observationally expensive due to the requirement for multi-epoch spectroscopy. To date only about 60 AGN masses have been obtained using this technique.
Using Bayesian methods found in Zu et al. (2011), we extract time-lags using only photometric data. By selecting our targets’ redshift such that H-beta emission will fall within the H-alpha narrow band filter of the Liverpool Telescope (0.35 z 0.40), we can increase the sample size of reverberation mapped AGN by ~20%. We investigate the efficacy of this method over 10 bright QSOs with known velocity dispersions.