Science

I am broadly interested in planetary and exoplanetary atmospheres, star and planet formation, and synergies between planetary and exoplanetary science. I use observations of brown dwarfs and solar system planets to improve our understanding of exoplanets: how they formed, what they are made of, and how they are evolving. Currently, I’m using the PEAS instrument that I designed and built to observe solar system planets as if they are point source exoplanets. I’m also using the NIRSPEC instrument, which I helped upgrade for Keck Observatory, to study the atmospheres of brown dwarfs at high spectral resolution. Stay tuned for more! Summaries of previous brown dwarf studies are below.

Infrared Spectroscopy

surface gravity examples in L dwarfs
J-band spectra of three L3 type brown dwarfs with low, intermediate, and high gravity. The potassium and iron hydride absorption features are used to trace surface gravity in brown dwarf atmospheres.

I studied surface gravities of brown dwarfs using gravity-sensitive features in the J-band spectra of brown dwarfs. I measured neutral potassium and iron hydride absorption to characterize surface gravity, in order to disentangle the effects of mass, temperature, and age on these brown dwarf spectra. Our paper was recently published in the Astrophysical Journal, and on the arxiv: Surface Gravities for 228 M, L, and T Dwarfs in the NIRSPEC Brown Dwarf Spectroscopic Survey

Astrometry

wise0410_astrometry
(Left) Astrometric measurements of a Y dwarf, WISE 0410+1502. (Right) Parallactic ellipse, after the proper motion component has been removed.

I recently published a paper in which we measured distances to the coldest brown dwarfs in the Solar Neighborhood. We use Spitzer IRAC channel 2 images over baselines of >2 years to measure the motions of these cool objects. Having precise distances allowed us to measure the absolute magnitudes and infer information about the temperatures of these cold, nearby objects.

Publications

ADS

ORCID