UC Berkeley

This thesis focuses around using the Gemini Planet Imager (GPI), an instrument designed to directly-image exoplanets, as part of the GPI Exoplanet Survey (GPIES), a multi-year survey to image and characterize Jovian exoplanets orbiting at Solar System Scales (5-100~au). The first half of this thesis is on building the data analysis infrastructure for GPIES. I helped commission GPI by characterizing the ability to measure the position and flux of a star when it is placed behind an occulting mask specifically designed to suppress starlight. I also led the development of the automated data processing infrastructure for GPIES that handles all of the data storage, indexing, and processing. This data infrastructure has optimized survey execution, ensured uniform data products, and characterized instrument performance. In the second half of this thesis, I characterize two notable exoplanetary systems through precise astrometry and orbital analysis. I present improvements to astrometric data analysis that allow us to measure the position of $\beta$ Pic b to one milliarcsecond, the most precise astrometry of an exoplanet to date. I tighten constraints on its orbit, including timing a window in which circumplanetary material of this young exoplanet could be transiting the star. Lastly, I apply the same astrometry techniques to the HR 8799 system which harbors four Jovian exoplanets. I added dynamical stability priors on my orbit fits using an N-body integrator to find stable orbits in the system. Through this, I explore possible orbital resonances and place dynamical constraints on the masses of the planets.