A deeper view of the CoRoT-9 planetary system: A small non-zero eccentricity for CoRoT-9b likely generated by planet-planet scattering

• Autor(a) principal: Bonomo, A. S.
• Data de Publicação: 2017
• Outros Autores: Hébrard, G., Raymond, S. N., Bouchy, F., Lecavelier Des Etangs, A., Bordé, P., Aigrain, S., Almenara, J. M., Alonso, R., Cabrera, J., Csizmadia, Sz., Damiani, C., Deeg, H. J., Deleuil, M., Díaz, R. F., Erikson, A., Fridlund, M., Gandolfi, D., Guenther, E., Guillot, T., Hatzes, A., Izidoro, A. [UNESP], Lovis, C., Moutou, C., Ollivier, M., Pätzold, M., Rauer, H., Rouan, D., Santerne, A., Schneider, J.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1051/0004-6361/201730624; http://hdl.handle.net/11449/169906
• topic: Planetary systems; Stars: Individual: CoRoT-9; Techniques: Photometric; Techniques: Radial velocities

CoRoT-9b is one of the rare long-period (P = 95.3 days) transiting giant planets with a measured mass known to date. We present a new analysis of the CoRoT-9 system based on five years of radial-velocity (RV) monitoring with HARPS and three new space-based transits observed with CoRoT and Spitzer. Combining our new data with already published measurements we redetermine the CoRoT-9 system parameters and find good agreement with the published values. We uncover a higher significance for the small but non-zero eccentricity of CoRoT-9b () and find no evidence for additional planets in the system. We use simulations of planet-planet scattering to show that the eccentricity of CoRoT-9b may have been generated by an instability in which a ∼ 50 M⊕ planet was ejected from the system. This scattering would not have produced a spin-orbit misalignment, so we predict that the CoRoT-9b orbit should lie within a few degrees of the initial plane of the protoplanetary disk. As a consequence, any significant stellar obliquity would indicate that the disk was primordially tilted.