Spitzer Space Telescope - Directors Discretionary Time Proposal #288 The Evolution of Infrared-luminous Galaxies at High Redshift Principal Investigator: Alexandra Pope Institution: U. British Columbia Science Category: ULIRGS/LIRGS/HLIRGS Observing Modes: IRS Staring Hours Approved: 13.2 Abstract: My primary goal is to understand how different populations of infrared-luminous galaxies are related to each other, and how they all fit into our picture of galaxy evolution. This goal will be addressed using upcoming deep, wide-field Spitzer and SCUBA-2 extragalactic surveys, along with multi-wavelength imaging and spectroscopic data. I will use these datasets to constrain the shape of the IR SED to obtain accurate estimates of the star formation rates and dust properties. I will use IRS observations to characterize the mid-IR SED as a function of redshift, luminosity and sample selection to separate AGN and starburst components.