THE EVOLUTION OF THE FAR-UV LUMINOSITY FUNCTION AND STAR FORMATION RATE DENSITY OF THE CHANDRA DEEP FIELD SOUTH FROM z=0.2 TO. 1.2 WITH SWIFT/UVOT

We use deep Swift UV/Optical Telescope (UVOT) near-ultraviolet (1600-4000 angstrom) imaging of the Chandra Deep Field South to measure the rest-frame far-UV (FUV; 1500 angstrom) luminosity function (LF) in four redshift bins between z = 0.2 and 1.2. Our sample includes 730 galaxies with u < 24.1 mag. We use two methods to construct and fit the LFs: the traditional V-max method with bootstrap errors, and a maximum likelihood estimator. We observe luminosity evolution such that M* fades by similar to 2 mag from z similar to 1 to z similar to 0.3, implying that star formation activity was substantially higher at z similar to 1 than today. We integrate our LFs to determine the FUV luminosity densities and star formation rate densities (SFRDs) from z = 0.2 to 1.2. We find evolution consistent with an increase proportional to (1 + z)(1.9) out to z similar to 1. Our luminosity densities and star formation rates are consistent with those found in the literature. but are, on average, a factor of similar to 2 higher than previous FUV measurements. In addition, we combine our UVOT data with the MUSYC survey to model the galaxies' ultraviolet-to-infrared spectral energy distributions and estimate the rest-frame FUV attenuation. We find that accounting for the attenuation increases the SFRDs by similar to 1 dex across all four redshift bins.