Optical through radio observations of dust-obscured starbursts and implications for massive galaxy evolution in the early Universe

Far-infrared and (sub)millimeter-bright galaxies are relatively rare in the local Universe, but known to be common at earlier epochs having been observed to dominate the cosmic star formation rate beyond a lookback time of eight billion years, i.e. redshift (z) >1. These systems are distinguished by their high dust mass, as well as the powerful bursts of star formation they undergo, and are capable of forming stars at one thousand times the rate of the Milky Way. In this doctoral thesis, I utilize optical through radio observations to determine the redshifts and physical properties of extreme starbursts, known as dusty star-forming galaxies (DSFGs), at two distinct epochs. I first examine DSFGs around the peak of cosmic star formation at z [approximately equal to] 2, a.k.a. cosmic noon, at which time they contribute roughly half of the Universe’s total star formation. Through this study I ascertain a link between morphology and radio luminosity and the importance of major mergers and interactions in triggering the DSFG phase of galaxy evolution. The sample of sources is selected from the Super-Cluster Assisted Shear Survey (SuperCLASS) and I present a multi-band photometric catalog I assembled covering the 2deg² survey. This catalog includes optical/mid-infrared photometry and photometric redshifts derived from fitting stellar population synthesis and AGN models to over 375,000 sources. Pushing on to even earlier times, within the first two billion years of the Universe (z>3), I then present a focused analysis of two z [approximately equal to] 4 DSFGs observed at 2-millimeters with the Atacama Large Millimeter/submillimeter Array (ALMA) as part of the Mapping Obscuration to Reionization with ALMA (MORA) survey. The physical characteristics of these two galaxies are consistent with a class of extremely dust-obscured, optically/near-infrared (OIR) invisible DSFGs in the literature. Ultimately, I provide evidence supporting the current theory that “OIR-dark” DSFGs are the progenitors of recently discovered 3<z