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

BONOMO, ALDO STEFANOALDO STEFANOBONOMOHébrard, G.G.HébrardRaymond, S. N.S. N.RaymondBouchy, F.F.BouchyLecavelier des Etangs, A.A.Lecavelier des EtangsBordé, P.P.BordéAigrain, S.S.AigrainAlmenara, J. -M.J. -M.AlmenaraAlonso, R.R.AlonsoCabrera, J.J.CabreraCsizmadia, Sz.Sz.CsizmadiaDamiani, C.C.DamianiDeeg, H. J.H. J.DeegDeleuil, M.M.DeleuilDíaz, R. F.R. F.DíazErikson, A.A.EriksonFridlund, M.M.FridlundGandolfi, D.D.GandolfiGuenther, E.E.GuentherGuillot, T.T.GuillotHatzes, A.A.HatzesIzidoro, A.A.IzidoroLovis, C.C.LovisMoutou, C.C.MoutouOllivier, M.M.OllivierPätzold, M.M.PätzoldRauer, H.H.RauerRouan, D.D.RouanSanterne, A.A.SanterneSchneider, J.J.Schneider2020-12-042020-12-0420170004-6361http://hdl.handle.net/20.500.12386/28693<ASTROBJ>CoRoT-9b</ASTROBJ> 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 <ASTROBJ>CoRoT-9</ASTROBJ> 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<SUB>⊕</SUB> 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.STAMPAenA deeper view of the CoRoT-9 planetary system. A small non-zero eccentricity for CoRoT-9b likely generated by planet-planet scatteringArticle10.1051/0004-6361/2017306242-s2.0-85022188200000406619100121https://www.aanda.org/articles/aa/full_html/2017/07/aa30624-17/aa30624-17.html2017A&A...603A..43BFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation::PE9_6 Stars and stellar systems