FLASH Talks: Casey Lam (UC Berkeley)
Friday, 16 September 2022 1 p.m. — 2 p.m. MST
Accurate mass measurements for supermassive black holes (SMBHs) are critical for understanding their growth over cosmic time. Outside of the local Universe, reverberation mapping (RM) of active galactic nuclei (AGN) is the most accurate method for measuring SMBH masses. RM measures the time lag between the continuum and broad emission line region (BLR) variability of AGN, which gives the virial mass when combined with the broad line width. I will present the latest results from the Dark Energy Survey (DES) - Australian DES (OzDES) RM project, which monitored 735 AGNs for 6 years with weekly photometry and monthly spectroscopy. Our results include some of the highest-quality Mg II lags and a new relationship between the radius of the Mg II BLR radius and the continuum luminosity (R-L relation). I will also describe our latest results on the Hbeta and C IV R-L relation. These R-L relations are extremely important because they are widely used to estimate the masses for large numbers of SMBHs from single-epoch spectra and study the SMBH demographics in a wide range of redshift. I will also present AGN accretion disk size measurements from continuum reverberation mapping, and simulations of the survey strategy of future RM campaigns to maximize the scientific yields.