The Hydrodynamic Histories of Elliptical Galaxies

Ohio University, Athens OH

Investigators

Abstract

AST-0708284 Statler The primary conceptual bottleneck in our understanding of the formation of galaxies is feedback: the entropy and thermal energy injected into the protogalactic interstellar medium by stellar winds, supernovae, and accreting supermassive black holes. The first comprehensive survey of X-ray gas morphology in normal elliptical galaxies has shown that the gas is rarely, if ever, in hydrostatic equilibrium, but is being continually pushed about by modest outbursts from comparatively weak active galactic nuclei (AGN). It also revealed three new, fundamental correlations that constrain the thermodynamic state of the gas and its relation to AGN activity. This project will elucidate the hydrodynamic histories of elliptical galaxies, and constrain the physical nature of feedback, using these new correlations, coupled with detailed hydrodynamical simulations. These simulations will progress to increasing complexity, in order to isolate the effects of quiescent AGN feedback, merger-induced AGN feedback, and merger-induced star formation and supernova feedback. The results will contribute to the ability to perform realistic simulations of structure formation on cluster, supercluster, and cosmological scales. The project supports a new collaboration between Ohio University and Los Alamos National Laboratory, helping to foster close ties between the national centers and academia. The associated graduate student will receive scientific and technical training in current research tools, including parallel computing. The research activities will also enhance the vigorous series of public programs carried on by the PI and his fellow faculty at Ohio University, which serves a traditionally underserved broader community. The results will be used in the PI's astronomy-related radio broadcasts and newspaper column.