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arXiv · 1903.07186

Long-Period Giant Companions to Three Compact, Multiplanet Systems

Sean M. Mills·Andrew W. Howard·Lauren M. Weiss·Jason H. Steffen·Howard Isaacson·Benjamin J. Fulton·Erik A. Petigura·Molly R. Kosiarek·Lea A. Hirsch·John H. Boisvert
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Abstract

Understanding the relationship between long-period giant planets and multiple smaller short-period planets is critical for formulating a complete picture of planet formation. This work characterizes three such systems. We present Kepler-65, a system with an eccentric (e=0.28+/-0.07) giant planet companion discovered via radial velocities (RVs) exterior to a compact, multiply-transiting system of sub-Neptune planets. We also use precision RVs to improve mass and radius constraints on two other systems with similar architectures, Kepler-25 and Kepler-68. In Kepler-68 we propose a second exterior giant planet candidate. Finally, we consider the implications of these systems for planet formation models, particularly that the moderate eccentricity in Kepler-65's exterior giant planet did not disrupt its inner system.

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Sean M. Mills, Andrew W. Howard, Lauren M. Weiss, Jason H. Steffen, Howard Isaacson, Benjamin J. Fulton, Erik A. Petigura, Molly R. Kosiarek, Lea A. Hirsch, John H. Boisvert. 2019-03-17. Long-Period Giant Companions to Three Compact, Multiplanet Systems. https://doi.org/10.3847/1538-3881%2Fab0899

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