ES-04-0001

The Kepler Giant Planet Search: Connections between the Orbital Spacings of Inner Planets and Outer Giant Planets in Extrasolar Systems

Matthias Yang He

Our Solar System consists of several giant planets ? namely Jupiter and Saturn ? orbiting beyond four smaller, terrestrial planets. However, it is unclear if this architecture extends to planetary systems around other stars, i.e. “extrasolar” systems. While the NASA Kepler mission discovered thousands of exoplanets between the sizes of Earth and Neptune at short separations (less than 1 AU) from their host stars, it was not sensitive to planets at larger separations. I will describe how we use the recently analyzed catalog of systems from the Kepler Giant Planet Search (KGPS), a systematic survey of giant planets in Kepler systems using the radial velocity method, to study correlations between the arrangements of the inner transiting planets and the presence of outer giant planets. I will show that in the KGPS systems with at least three transiting planets, those with an outer giant planet (defined as greater than the mass of Saturn) tend to have significantly more irregularly-spaced orbits than those without any outer giants, in the form of exhibiting larger “gap complexities” (a measure of the deviation from uniformity in orbital spacing). Our finding suggests that one can predict the occurrence of outer giant companions by selecting planetary systems with highly irregular spacings, and hints that massive external planets play an important role in the formation and/or disruption of the inner systems.