Identifying Circumbinary Planets Using Precession Analysis

Circumbinary planets, which orbit two stars, make up a small discovered population. All 15 systems have been found via the transit method: observing the light from a star for periodic dips in brightness caused by a planet passing in front of it. However, this method can only detect planets that directly pass in front of their host stars and are not inclined to our observational plane, limiting our understanding of system geometries. We search for circumbinary planets through precession, a method unaffected by this bias. Precession is observed as slight changes in the orbital axis of the stars from the gravitational tug between the stars and planet, rotating their orbits around the system’s center of mass. We investigate how the relative timing of primary and secondary eclipses evolve over decades for 586 binary systems, combining data from ground and space-based photometry surveys. I present preliminary results of systems with observed precession larger than can be caused by general relativity and tidal effects. These findings will help us better understand the architectures of circumbinary systems, determine whether they only form in flat, aligned configurations, understand the conditions allowing these planets to form, and explore the types of binaries that host planets.