I am currently a PhD candidate at Steward Observatory at University of Arizona. I study exoplanet formation and evolution, particularly in binary star systems, through direct imaging and high-contrast imaging ground-based observations. I'm a part of the MagAO-X team, the extreme adaptive optics instrument on the Magellan Clay telescope in Chile. I have also worked with Keck/NIRC2 images, and with unresolved companions in stellar binaries in Gaia.

Binary Differential Imaging

Planets are much much fainter than stars. In order to image a planet directly, we must remove the influence of the starlight to reveal the faint source lying underneath. Binary Differential Imaging leverages the advantage of simultaneously imaging a science target and a star to use to build a model of the point spread function by imaging both stars in a binary in a single image, and using each star as the reference for the other. I reduced a binary differential imaging dataset of 17 binaries imaged in L-prime band with MagAO/Clio on the Magellan Telescope from 2014-2017 using principle component analysis to recontruct the starlight model.

Boyajian's Star's Wide Companion

Boyajian's Star (aka KIC 8462852, aka Tabby's Star) has made waves in both astrophysics and the popular imagination due to its enigmatic light curve from the Kepler space telescope that is not well explained yet by any physical (or alien) theory (hint: it's not aliens). I showed that it has an here-to-fore unconfirmed wide stellar companion currently ~880 AU away. The companion is not an explanation for the light curve (despite claims to the contrary) but it is another piece of the puzzle.

Gaia RUWE as an indicator of multiplicity

The Gaia astrometric satellite assumes each point source is a single star to fit astrometry to its motion. So the presence of subsystems unresolved in Gaia will cause the motion to deviate from a single star, and cause error in the fit. The error is encapsulated in the Renormalized Unit Weight Error (RUWE) term. Thus, RUWE can be used as a signpost of the presence of unresolved multiple stars.
In this unpublished mini-lit review I summarize recent work on RUWE and what it can reveal about unresolved multiples in Gaia DR2 and EDR3.
Image: Figure 1 from Belokurov et al. 2020 showing an HRD of selected Gaia sources, color coded by RUWE. The marked regions correspond to MS multiples and white dwarf + M-dwarf binaries, which also show elevated RUWE, illustrating that RUWE is sensitive to multiplicity.

Orbit Fitting of Wide Stellar Binaries with Gaia

The Gaia astrometric satellite provides unprecedented accuracy of astrometry motion. I showed that the relative velocity between two stars in a wide binary, for which both stars are well resolved by Gaia and have high quality astrometric solutions, can be used to constrain the orbital elements of the binary orbit.
I produced an open source python package that automatically fits orbital elements for two Gaia EDR3 sources with just the source ID numbers and a mass estimate for each.

Orbital Motion of Wide Planetary-Mass Companions to Low-Mass Stars

Planetary mass companions are large mass planets (on the order of 15 Mjup) on wide orbits (100’s of AU) from their host stars. They exist in a parameter such that it is unclear if they represent the high end of planetary masses, the low end of brown dwarf masses, or if there is even is a dividing line in the substellar mass function at all. I measured precise milliarcsecond astrometry of the PMC GSC 6214-210 B in 10 years of Keck/NIRC2 images, and fit the motion for orbital elements using the Orbits for the Impatient rejection sampling algorithm.