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