http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Tracking Galaxy Growth During the Past 11 Billion Years with Deep Near Infrared Surveys
Using observations from the FourStar Galaxy Evolution Survey (ZFOURGE), we obtain the deepest measurements to date of the galaxy stellar mass function (SMF) at z < 3. With these data, we find evidence for a steepening of the slope at the low-mass end of the SMF at z ⁹́Þ 2, a feature that had only been identified at z ⁹́Þ 1. These measurements also allow us for the first time to observe a rapid buildup of low-mass quiescent galaxies and help to constrain the growth rates of galaxies. We next explore star-formation histories (SFHs) of galaxies based on the evolution of the correlation between the star-formation rate and stellar mass of galaxies (SFR⁸́₂M⁸́₇) and compare to the buildup of stellar mass predicted from the evolution of the SMF. By integrating along the SFR⁸́₂M⁸́₇ sequence we generate differential SFHs and estimate stellar mass-growth histories. We find that these integrated SFHs are in broad qualitative agreement with the SMF, but that they do disagree in detail. At early times the SFHs suggest mass-growth rates that are as much as 0.5 dex higher than inferred from the stellar mass function. Lastly, we look into the prevalence of a possible source of feedback preventing star-formation using mid-IR data from the Spitzer Space Telescope with established color selection criteria to identify galaxies hosting active galactic nuclei (AGN). Of the 949 cluster galaxies in our IR-detected sample we identify 12 that are consistent with hosting AGN. We thus measure the fraction of cluster galaxies that host an IR-AGN for a magnitude-limited subsample (fIR⁸́₂AGN) to be ⁹́⁸ 0.6% with a strong upper limit of 3.4% at the 99% confidence level at z < 1. Our results suggest that fIR⁸́₂AGN in massive galaxy clusters is not strongly correlated with star formation at z < 1, and that IR-AGN have a more prominent role at z > 1. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/155705
Doctor of Philosophy Texas A & M University 2015 http://hdl.handle.net/1969.1/155705