This research will carry out a complete census of low-luminosity and unusual Active Galactic Nuclei (AGN), in order to quantify the full populations of these objects and to understand the evolution of super-massive black holes as it relates to the evolution of the galaxies in which they reside. Assembling various catalogs based on the Sloan Digital Sky Survey, the PI will determine the faint end of the AGN luminosity function (which is absolutely crucial for understanding the dramatic change in the observed number density of luminous quasars as a function of redshift), explore the relationships between AGN and their host galaxies and their environment, and quantify the physical nature of obscured and reddened AGN. Astronomers believe that AGN are powered by accretion disks, and quasar emission line profiles are an important probe of accretion physics: this research will also address the puzzle of why only a small subset shows double-peaked emission lines. Furthermore, the PI will study those objects with featureless spectra, and thus test models for AGN unification.
The PI will continue his record of engaging students from high school to graduate school in the research, which will also be incorporated into undergraduate and public lectures. His exciting results will be shown at Princeton's student center on their electronic wallpaper, and via the astro-bulletin, a large video display at the Hall of the Universe in the Rose Center for Earth and Space Science (American Museum of Natural History).
