Research

I'm the newly appointed co-PI of the 4MOST consortium survey 1001 Magellanic Fields (1001MC). Scheduled to begin in early 2025, the survey will provide medium-resolution spectra for over a million Magellanic stars across the HR diagram - orders of magnitude more than existing spectroscopic surveys! 

I'll use this data to create a full chemodynamical map of the Clouds, investigating their interaction history and searching for signals of accreted halo populations. 

While at JHU, I led analysis of data from the Triangulum EXtended Survey (TREX). TREX is an ongoing spectroscopic survey using Keck/DEIMOS to map individual stellar kinematics for a variety of stellar populations across the M33 disk and outskirts. We find evidence for an old "halo" (i.e. high-dispersion) population, concentrated at small galactocentric radii, as well as an intermediate-age halo component that appears systematically kinematically offset from the galactic disk. I'm contnuing work to better model the system and derive coadded metallicities and alpha-abundances for the stars, helping to constrain the properties and origin (e.g. accreted vs kicked-up disk stars) of the halo populations.

I'm also involved in spectroscopic follow-up across M31's southern disk for the PHAST (Pan-chromatic Hubble Andromeda Southern Treasury) survey. 

I'm the PI of MagES, the Magellanic Edges Survey. MagES is an ongoing spectroscopic survey, using the 2dF/AAOmega instrument on the Anglo-Australian Telescope, of thousands of red clump and red giant branch stars in the extreme outskirts of the Magellanic Clouds. MagES specifically targets stars in low-density, low-surface brightness features surrounding the Clouds: remnants of past interactions between the two Clouds themselves, as well as the Milky Way. By using MagES data to derive precise line-of-sight velocities, in combination with astrometry from the Gaia satellite, I derive full 3D kinematics for a large population of individual stars in these substructures: a completely unique dataset that is invaluable in tracing back the interaction history of the Clouds and understanding how these features form. 

We find some features are due almost entirely to the Clouds first infall into the Milky Way potential, while others require multiple close passages between the Clouds themselves: one of the first times we've been able to start placing constraints on the early orbits of the Clouds prior to their most recent close passage! 

I'm a builder member and regular observer for the Southern Stellar Stream Spectroscopic Survey (S5) collaboration. S5 uses the 2dF/AAOmega spectrograph on the Anglo-Australian Telescope (as well as high-resolution follow-up) to map the chemistry and kinematics of 20+ stellar streams in the Milky Way halo (now expanded to include tidal tails from globular clusters and a handful of dwarf galaxies), and shed light on their progenitors, as well as their evolution. You can find out more about the survey on the S5 website, including the first public data release.