Tidal Tails
Tidal tails form during galaxy-galaxy interactions. These features contain material stripped from the host galaxies, such as stars, and hydrogen gas. At the same time, they are great places for stars to form, as turbulence within the tail compresses the gas and ignites star formation. My research involves deep optical observations of systems with tidal tails to search for these two stellar populations: old stars formed in the host galaxies and pulled into the tail, and new stars formed in the interaction. We combine our observations with archival HI data to get a more complete, multi-wavelength survey of tidal tails.
Quasar Variability
Quasar spectra are host to a multitude of absorption lines, originating from intervening systems in the line of sight between us and the quasar, and from material in the quasar system itself. These intrinsic lines can generally be classified by their line widths as Broad Absorption Lines (BALs), mini-Broad Absorption Lines (mini-BALs), and Narrow Absorption Lines (NALs). We know that it is common for the strength of BALs and mini-BALs to vary, but few studies have looked at the variability of NALs. I am using data from the VLT UVES archive and Keck HIRES archive to search for variability in NALs. The variability time scale lets us determine gas densities, and thus the distances from the central engines