The Search for Gravitationally Bound Companions to Kepler Objects of Interest: an Astrometric Study Using Speckle Imaging Over a Decade

We report on the updated dispositions of 37 Kepler Objects of Interest with companion stars as either line-of-sight or common proper motion pairs. These targets were previously selected for follow-up from the Kepler mission to be observed using speckle imaging to determine whether the stellar pairs were gravitationally bound. Originally flagged as potential exoplanet hosts, these systems were found to have two or more stellar components that could interfere with photometric planetary analysis and potentially impact the study of orbital dynamics of the putative planets if the stellar pairs are gravitationally bound. Previous work on these systems has been updated with relative astrometry and photometry from new speckle observations using DSSI at APO as well as system parameters in Gaia’s third data release. The new data have directly improved the dispositions of eight systems and decreased uncertainty across the sample as a whole. We find that 25 of the systems in our sample exhibit common proper motion, five are line-of-sight pairs, and seven remain of uncertain disposition. Additionally, we examined systems within our sample for which Gaia resolved the same components we resolve with speckle imaging. In these nine case, we compare the Bailer-Jones distances for each system component to see if both components are located at the same, or different, distances. When comparing this complimentary technique against our results, we find the two methods largely agree.