connections between active galactic nuclei and galaxy bulges

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Turbulent magnetic friction in an accretion disk of matter spiralling into a supermassive black hole at the center of a galaxy can cause the infalling matter to heat up and give off the light we see as an Active Galactic Nucleus (AGN). Exactly how this process works is not understood, but various lines of argument do suggest that a wind launched from the accretion disk will carry away angular momentum and allow matter to fall into the black hole. These winds affect the formation and development of galaxies and distribute metal-enriched gas into intergalactic space. What is needed now is a detailed comparison of the optical and ultraviolet properties of thousands of AGN with wind model predictions. Knowing which kinds of winds reproduce the observations will help refine theoretical wind models and improve our ability to infer the fundamental physical parameters of AGN from their observable parameters. Better understanding of AGN winds will lead to better understanding of AGN and of how galaxies have been influenced by AGN feedback.Another way to study AGN feedback is to assemble a large sample of galaxies with measurements of both central stellar bulge and black hole properties and study the connections between those properties. Together, the Canada-France-Hawaii Telescope Legacy Survey and spectroscopic surveys such as the Sloan Digital Sky Survey can provide such a sample.  The deep, high-resolution imaging of the CFHTLS enables separation of the light from many galaxies into the light from their stellar bulges, stellar disks, and active nuclei. Bulge luminosity is correlated with black hole mass in a relationship that can be calibrated using the width of emission lines from a galaxy's active nucleus. Combining the CFHTLS with publicly available spectroscopic surveys will enable the best study yet of the behavior of the black hole mass - bulge luminosity correlation over four orders of magnitude in black hole mass, setting important constraints on theoretical models of galaxy formation and AGN feedback.