Dusty Galaxies in the Distant Universe
Ten billion years ago, the universe was an exciting place, forming 50% of the stars we see today and concurrently feeding the supermassive black holes that reside at the center of every large galaxy. Yet, the most active galaxies were shrouded in dust, obscuring their newly formed stars and active supermassive black holes. In fact, these galaxies have 10 times more dust and are significantly colder than galaxies of the same luminosity in our local universe. I use Herschel and Spitzer observations to explore the reasons for this "cooling" of galaxies and it's implication for how they evolve. I also discuss how, in unresolved observations of galaxies, we can distinguish between young stars and an active supermassive black hole as the primary heating mechanism of the interstellar medium. I use infrared techniques to quantify how many galaxies in the distant universe are harboring hidden black holes, and I discuss what effect these black holes can have on the interstellar medium in their host galaxies.
