Characterizing Stars and their Planets
Know Thy Star…
I am interested in precisely and accurately measuring the fundamental characteristics of stars, including their masses, radii, and effective temperatures, in order to reconcile discrepancies between observed properties of some stars (such as the M dwarf radius and effective temperature discrepancies) and those predicted by models of stellar evolution. For isolated stars, my current work focuses on combining Gaia parallaxes with broad-band flux measurements to determine radii and effective temperatures by modeling the stellar spectral energy distribution (SED). I developed a quick method to determine these quantities and applied them to the Tycho-Gaia Astrometric Solution sample here.
..Know Thy Planet (or Thy Low-mass Stellar Companion)
I am also interested in constraining the physical properties of eclipsing SB1s — transiting planetary systems and other low mass-ratio EBs. My ongoing work involves combining transit photometry, radial velocity (RVs) observations of the primary star, the SED, and a parallax to calculate the physical parameters of the individual stars and planets without relying upon stellar evolutionary models. I examined the contributions to the mass and radius uncertainties from this and other methods here. I am using these results to test stellar models and to see what we can infer about the composition of transiting planets.
Extreme Stellar Systems
The high-precision and continuous photometric observations from space telescopes like Kepler and TESS, combined with the 10+ years of ground-based observations from surveys like the Kilodegree Extremely Little Telescope (KELT) survey, are opening new frontiers in stellar astrophysics by finding rare types of eclipsing SB1s. I led the characterization of HD 58730, a spin-orbit aligned, pre-main sequence M-type star eclipsing a late-B type dwarf. I also contributed to the characterization of HD 149834, a K-type star being highly irradiated by a hybrid-pulsating mid-B star, found in a cluster and showing anomalous high-energy flux emission. Binaries in configurations like these are rare, and the combinations of eclipses, RVs, SEDs, astrometry, irradiation and pulsation signals, and/or cluster memberships enable complementary methods of determining fundamental stellar parameters to test stellar models in new regimes.
Planet Hunting
The KELT Survey
I hunted for transiting exoplanets as part of the KELT survey from 2014-2020,. From 2014-2018, I ran the data processing and planet-candidate selection pipelines for the KELT-North telescope and coordinated follow-up observations of the planet candidates.
I led the discovery and characterization of KELT-12b, one of the most “inflated” hot Jupiters, which transits a hot star at the end of its core hydrogen burning days. I also coordinated follow-up for seven other confirmed KELT-North planets: KELT-8b, another one of the most inflated hot Jupiters known; KELT-9b and KELT-20b, two of the hottest planets orbiting two of the hottest and brightest stars known to host planets; KELT-16b, a hot Jupiter whipping around its host star on a <1-day orbit; and KELT-21b, which orbits one of the fastest rotating stars confirmed to host a transiting planet.
Undergraduate Work
I worked with Will Farr, Ilya Mandel, and Vicky Kalogera on developing an efficient, kD-tree based interpolation technique for MCMC jump proposals for the LIGO parameter estimation pipeline. My undergraduate thesis can be found here, and a paper on the topic can be found here.