8 May 2008

Speaker: Kim McLeod (Wellesley College)

Title: Probing the Assembly of Massive Galaxies via Quasar Hosts at z=4

Abstract: One decade has now passed since near-IR imaging reoutfitted the "naked" quasars, and since HST gave us our first detailed look at low-redshift quasar host galaxies. At the same time, the discovery of the universal correlation between the masses of galaxies and their central black holes has ushered in a new generation of models of galaxy evolution. High-redshift quasars provide excellent leverage for tests of these models. As objects that already contain supermassive black holes at early times, they are destined to evolve into today's largest ellipticals. Yet surprisingly few host-galaxy redshift. In this talk, I will explain why as I present deep, near-IR images of 34 quasars at z=4 taken at the Magellan I and Gemini North telescopes. I will describe the search for their hosts and will use the results to constrain the evolution of the black hole/bulge relation. I will also describe how observations of their environments can reveal the pieces that will merge over cosmic time to become today's behemoths.

Video of the Presentation (Talks can be viewed with RealPlayer. Free download is available from www.real.com )