Growing Supermassive Black Holes in a Young Universe

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Every massive galaxy in the local universe hosts a supermassive black hole in its centre. Billions of years ago, these black holes grew as luminous quasars as gas fell into the black hole during the same era that most stars were born within these galaxies. The nature of the relationship between these two processes remains an active research topic. What is known is that large disks of in-falling gas power the quasars and can outshine the hundreds of billions of stars in their galaxies a thousand times over. With the radiation pressure from this light on gas and dust in the quasars' inner regions, these small powerhouses can launch energetic winds that impact the star-forming environment in their galaxies. The quasar phase is thus an important and dramatic event in the early evolution of every massive galaxy. Despite their tremendous luminous energies that enable them to be observed at great distances, quasars are quite small compared to their galaxies and the details of their inner structure remain elusive. I propose a diverse program to probe the quasar system on multiple scales, moving outward from the structure of the accretion disk, to the fast, ionized wind, then to the cooler, dusty wind, and finally to the host galaxy. Specifically, my science objectives are to:***(1) Develop a next-generation observing program to map the central few light years of thousands of quasars. By modelling variability of a diverse population of quasars, we will design the optimal experiments to take advantage of the exciting capabilities of large-field, multi-object spectrographs on 10-m class telescopes to advance our understanding of the inner structure of quasars.***(2) Use the wind signatures in quasar spectra to constrain the geometry of the winds. With ground-based spectroscopy and Chandra X-ray observations, we will measure the physical properties of thick winds to determine their potential to affect their host galaxies.***(3) Enhance our current model of dusty winds to predict new observations. A more sophisticated treatment of the interaction of light with the dusty wind will enable us to constrain wind geometry and physics by comparing to new results from innovative observing programs.***(4) Map star formation and gas motions in quasar host galaxies with advanced facilities. Learning about the large-scale properties of these galaxies will show us the link between building stars and growing black holes.****The quasar activity that builds supermassive black holes occurs at some point in the evolution of all massive galaxies. The comprehensive approach characterized by these four science objectives will incorporate new and archival observations and tested models to expand our understanding of black hole growth in a young universe.********