Tightening the Spin-Orbit Angle Demographics of Hot Jupiters

The angle between the stellar spin angular momentum and the planetary orbital angular momentum --- spin-orbit angle --- is one of the key parameters in understanding a planetary system's architecture and formation history. Traditionally, only a projected (or line of sight) version of this angle can be feasibly measured. A planet's true 3-D spin-orbit angle is more difficult to constrain; as such, only a handful of true spin-orbit angles have been determined to date. Our current research will significantly expand spin-orbit angle demographics by measuring true spin-orbit angles of hot Jupiters orbiting A/F-type stars observed by TESS, where spin-orbit misalignment is most common. We are measuring true spin-orbit angles using the gravity-darkening transit analysis technique, which applies specifically to high-mass, rapidly-rotating stars. With precision photometry from TESS, we have for the first time the opportunity to obtain true spin-orbit angles en masse in a straightforward and cost-effective way. Our team's proposed research will improve accessibility to studying planets transiting A/F stars, a subset that encompasses up to 40% of expected TESS planet discoveries. We will also measure valuable and difficult-to-obtain stellar parameters such as oblateness and effective temperature gradient, which will be necessary for future atmospheric studies of the selected planets.