Andrew Sheinis: Science

A growing understanding of the connection between galaxies and their central black holes has emerged over the last decade. The facts that all galaxies with a bulge contain supermassive black holes ; that black hole mass is correlated with galaxy stellar veloc- ity dispersion ; and that the inclusion of AGN feedback, or an equivalent energetic source to quench star formation above a critical halo mass, in semi-analytic galaxy for- mation models matches the galaxy demographics and bimodality of properties observed in large surveys (SDSS, COMBO-17, DEEP/DEEP2, MUNICS, FIRES, K20, GDDS), all suggest that the growth mechanisms of the black hole and galaxy must be connected. However, details of the physical processes that make this connection, such as how AGN energy interacts with and is dissipated by surrounding halo gas, are not yet known.

Studies of AGN host galaxies have reached different conclusions. ... In this work we study bright quasars in which the galaxy is actively feeding the central su- permassive black hole. It is here that we should be able to investigate interactions between the black hole and its surrounding galaxy from which we can draw conclusions about how the black hole may or may not affect galaxy formation and evolution. We analyze the QSO host galaxies by comparing their structural parameters to normal galaxies, relate this to their stellar populations and morphologies, and investigate how their black hole masses compare to quiescent galaxies and other AGN.