The highest redshift galaxies
Galaxies at z>6
Much of my work involves modeling the properties and distributions of the earliest galaxies. While the new WFC3 camera on the Hubble Space Telescope has discovered the highest redshift galaxies currently known at a time when the Universe was less than a billion years old, it is still unclear how similar these objects are to the very first galaxies that came before or whether they are merely high-redshift analogs of more modern systems. Additionally, given their extreme distance and brightness, the disparate techniques used to find these objects can introduce complicated biases in the observed distributions. I study to what extent we can overcome these issues and use the objects to learn about the formation of the first stars and galaxies and their interaction with the intergalactic medium.
The billion-particle Via Lactea II simulation of the dark matter in the Milky Way at z=0 (Diemand et al. 2008). The coloring indicates the local phase space density.
Relics in the Local group
New extremely high resolution numerical simulations of the Milky Way combined with detections of the faintest known satellite galaxies in the local group have made it possible to study the relationship between the very first galaxies and their relics in the present-day universe. We have helped pioneer techniques to explore galaxy and star formation at high redshift and the resulting feedback into the intergalactic medium using SDSS luminosity functions of Milky Way satellites modeled by the Via Lactea II simulation.
