AGN Science with the LSST

The LSST, with its unprecedented combination of sky coverage, photometric and astrometric accuracy, sensitivity, broad wavelength coverage, and time sampling, will provide a new window into the nature of AGNs. Well-defined, large (> 10⁷ objects) samples of AGNs at 0 < z < 6 can be constructed via three approaches: location in color-color space, variability, and lack of proper motion. The samples will allow determination of the AGN luminosity function down to Seyfert luminosities out to z ∼ 4. The near-infrared wavelength coverage/high sensitivity of LSST enables detection of the population of red quasars, and the proper motion criteria will be particularly effective at separating z > 4 AGNs from brown dwarfs. The time baseline coupled with the sample size will produce a data set that can be used to address the physics of the AGN accretion process, including insights into the lifetime of AGNs.