Abstract:  The Kepler mission revealed thousands of exoplanet candidates as well as hundreds of multi-transiting systems, which provide powerful insights into the correlations within planetary systems and their architectures if the detection biases are properly accounted for. In He, Ford, & Ragozzine (2019, 2020), we developed an advanced forward model (SysSim) for the Kepler catalog and showed that planets in the same system are clustered in periods and in sizes, the fraction of stars with planets (with Rp>0.5R_Earth and 3d<P<300d) increases towards later type (cooler) stars across the FGK range, and the observed multiplicity distribution can be well matched by two populations consisting of a low and a high mutual inclination component. Here, I will present a new model to show that a broad, multiplicity-dependent distribution of eccentricities and mutual inclinations arising from systems at the angular momentum deficit (AMD) stability limit can also reproduce the observed population. Systems with intrinsically more planets have lower eccentricities and mutual inclinations. This trend with multiplicity arises from a strong correlation of the critical AMD on the minimum period ratio in the system, as systems with tightly spaced planets must have low AMD in order to remain stable. We also find evidence that intrinsic single planets have higher eccentricities than multi-planet systems. I will show that there is evidence for these trends with multiplicity in the Kepler distributions of circular-normalized transit durations and transit duration ratios. I will also show that the observed preferences for the ordering of planets in increasing size and for their uniform spacings cannot be fully explained by detection biases, and are even more extreme than our simple clustering in periods and planet sizes. Finally, I will discuss how our simulated planet catalogs can be used to inform RV follow-up efforts in the search for additional non-transiting companions in systems with transiting planets, such as those observed from the TESS mission.

Please click the link below to join the webinar: https://psu.zoom.us/j/96060188956