Research Interests
Exoplanets: Discovery and characterization
My dissertation research is a direct imaging search for giant planets and brown dwarfs orbiting nearby, young, low-mass stars. The goals are to determine the frequency of giant planets at large separations around low-mass stars for the first time, which provides critical information about the planet formation process, and to identify young giant planets and brown dwarfs, which are amenable to follow-up spectroscopic observations.
One of the fundamental goals of exoplanetary science is to understand the formation and evolution of planets and their atmospheres. High contrast spectroscopy of faint companions is possible with existing instruments, especially integral field spectrographs, enabling detailed studies of planetary atmospheres outside our solar system for the first time.
The image at right shows the halo of a bright star (orange-green) and a small region of the halo subtracted out (blue-purple), revealing the known planet HR 8799 b. The image is in fact a data cube with each pixel representing a spectrum in the third dimension.
The analysis of this spectrum was published in 2010 in collaboration with Michael Liu, Trent Dupuy, and Michael Cushing. The press release from Keck Observatory can be found here.
PALMS: Planets Around Low-Mass Stars
A High Contrast Adaptive Optics Imaging Search for Giant Planets
Around Young M Dwarfs
The first discovery from the PALMS survey is a ~30 Jupiter mass brown dwarf companion to a young M dwarf. The discovery paper (to be published in The Astrophysical Journal) can be found here:
First Results
Spectroscopy of Planetary Companions