Photodynamical Modeling of All Kepler Multi-Transiting Systems: the Kepler Multis Dynamical Catalog

The ~750 systems of multiple transiting planets from the Prime Mission of the Kepler Space Telescope is the largest and most information-rich homogeneous exoplanet catalog. The fiducial “Data Release 25” catalog is the final homogeneous analysis by the Kepler mission, though Lissauer et al. 2023 provide some meaningful updates for multi-transiting systems. However, these catalogs are missing crucial dynamical and geophysical parameters — like masses and eccentricities — that are not directly constrained by Kepler observations. For ~20% of systems, these parameters can be constrained due to planet-planet gravitational interactions, most commonly manifested as Transit Timing Variations (TTVs). Existing TTV analyses have measured many Kepler masses, but are often sub-optimal because they fit only TTV meta-data that do not include non-Gaussian uncertainties, Short Cadence data, or simply do not exist for the smallest planets. Photodynamical analyses that couple n-body integrations directly to observed (detrended) light curves are near optimal, but have only been carried out for a small number of systems. We report on early results of our photodynamical analysis of all Kepler multi-transiting systems. We use our Bayesian “PhoDyMM” model with an detailed automation procedure and extensive supercomputer usage to perform photodynamical analyses of all 752 Kepler multi-transiting systems. Although most systems have no meaningful constraints on masses and eccentricities, the homogeneous nature of our analyses allows us to produce the first Kepler Multis Dynamical Catalog that includes posterior distributions for all major physical and orbital properties for all planets in all Kepler multis. We will present early results on our PhoDyMM analyses with an eye towards implications for underlying distributions of compositions, dynamics, and architectures.