Endl, Michael2; Caldwell, Douglas A.2; Barclay, Thomas2; Huber, Daniel2; Isaacson, Howard2; Buchhave, Lars C. Astrup4; Brugamyer, Erik2; Robertson, Paul2; Cochran, William D.2; MacQueen, Phillip J.2; Havel, Mathieu2; Lucas, Phillip2; Howell, Steve B.2; Fischer, Debra2; Quintana, Elisa2; Ciardi, David R.2
1 Astrophysics and Planetary Science, The Niels Bohr Institute, Faculty of Science, Københavns Universitet2 unknown3 Natural History Museum of Denmark, Natural History Museum of Denmark, Faculty of Science, Københavns Universitet4 Natural History Museum of Denmark, Natural History Museum of Denmark, Faculty of Science, Københavns Universitet
A "LONELY'' HOT JUPITER THAT FOUND A COMPANION
Hot Jupiter systems provide unique observational constraints for migration models in multiple systems and binaries. We report on the discovery of the Kepler-424 (KOI-214) two-planet system, which consists of a transiting hot Jupiter (Kepler-424b) in a 3.31 day orbit accompanied by a more massive outer companion in an eccentric (e = 0.3) 223 day orbit. The outer giant planet, Kepler-424c, is not detected transiting the host star. The masses of both planets and the orbital parameters for the second planet were determined using precise radial velocity (RV) measurements from the Hobby-Eberly Telescope (HET) and its High Resolution Spectrograph (HRS). In stark contrast to smaller planets, hot Jupiters are predominantly found to be lacking any nearby additional planets; they appear to be "lonely". This might be a consequence of these systems having a highly dynamical past. The Kepler-424 planetary system has a hot Jupiter in a multiple system, similar to Andromedae. We also present our results for Kepler-422 (KOI-22), Kepler-77 (KOI-127), Kepler-43 (KOI-135), and Kepler-423 (KOI-183). These results are based on spectroscopic data collected with the Nordic Optical Telescope (NOT), the Keck 1 telescope, and HET. For all systems, we rule out false positives based on various follow-up observations, confirming the planetary nature of these companions. We performed a comparison with planetary evolutionary models which indicate that these five hot Jupiters have heavy element contents between 20 and 120 M ⊕.