Research Interests

My general area of research is observational cosmology, with particular interest in the process of galaxy formation and the nature of the intergalactic medium. Whereas the large-scale structure of the universe is dictated primarily by dark matter, the behavior of the normal, baryonic matter embedded in the dark-matter structure is what shapes the observable universe. These baryonic processes are very complex, and relatively poorly understood. By using spectroscopic observations of objects at high redshifts, we attempt to observe directly the most important cosmic epochs as they are happening. Such observations are used to reconstruct the history of galaxies, and the reservoir of diffuse gas between the galaxies, over a large fraction of the age of the universe. We are interested in measuring key physical parameters of galaxies such as mass, chemistry, large-scale spatial distribution, and the impact of energetic processes such as black hole accretion, star formation, and supernova explosions on their environments in the young universe. Most of this work is conducted using large ground-based telescopes operating at optical and near-infrared wavelengths, and includes participation in the development of state-of-the-art instrumentation.

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Primary Section

Section 12: Astronomy