1:30–2:00 pm ERC 401
Jared Siegel "Constraining extrasolar planet masses with low-SNR Kepler TTV Data"
Supervisor: Professor Leslie Rogers
Abstract: Prospects for expanding the available mass measurements of the Kepler sample are limited. Planet masses have typically been inferred via radial velocity (RV) measurements of the host star or time series modeling of transit timing variations (TTVs) in multiplanet systems; however, the majority of Kepler hosts are too dim for RV follow-up, and only a select number of systems have strong enough TTVs for complex modeling. Here, we develop a method of constraining planet mass in multiplanet systems using low signal-to-noise ratio (SNR) TTVs. For a sample of 168 planets in 76 multiplanet systems from the California–Kepler Survey, we infer posteriors on planet mass using publicly available TTV time series from Kepler. For 55 planets (>30% of our sample), low-SNR TTVs yield informative upper bounds on planet mass---i.e., the mass constraint strongly deviates from the prior on mass and yields a physically reasonable bulk composition. For 23 small planets, low-SNR TTVs favor volatile rich compositions. Where available, low-SNR TTV-based mass constraints are consistent with RV-derived masses. Our methods offer a valuable path towards increasing the available mass constraints of the Kepler sample. TTV time series are publicly available for each Kepler planet, and the compactness of Kepler systems makes TTV-based constraints informative for a substantial fraction of multiplanet systems.