Author(s):
Izidoro, Andre [UNESP] ; Ogihara, Masahiro ; Raymond, Sean N. ; Morbidelli, Alessandro ; Pierens, Arnaud ; Bitsch, Bertram ; Cossou, Christophe ; Hersant, Franck
Date: 2018
Persistent ID: http://hdl.handle.net/11449/169929
Origin: Oasisbr
Subject(s): Disc interactions; Methods: Numerical; Planet; Planets and satellites: Dynamical evolution and stability; Planets and satellites: Formation; Protoplanetary discs; Disc interactions; Disc interactions; Methods: Numerical; Methods: Numerical; Planet; Planet; Planets and satellites: Dynamical evolution and stability; Planets and satellites: Dynamical evolution and stability; Planets and satellites: Formation; Planets and satellites: Formation; Protoplanetary discs; Protoplanetary discs
Description
Made available in DSpace on 2018-12-11T16:48:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-09-11
'Hot super-Earths' (or 'mini-Neptunes') between one and four times Earth's size with period shorter than 100 d orbit 30-50 per cent of Sun-like stars. Their orbital configuration - measured as the period ratio distribution of adjacent planets in multiplanet systems - is a strong constraint for formation models. Here, we use N-body simulations with synthetic forces from an underlying evolving gaseous disc to model the formation and long-term dynamical evolution of super-Earth systems. While the gas disc is present, planetary embryos grow and migrate inward to form a resonant chain anchored at the inner edge of the disc. These resonant chains are far more compact than the observed super-Earth systems. Once the gas dissipates, resonant chains may become dynamically unstable. They undergo a phase of giant impacts that spreads the systems out. Disc turbulence has no measurable effect on the outcome. Our simulations match observations if a small fraction of resonant chains remain stable, while most super- Earths undergo a late dynamical instability. Our statistical analysis restricts the contribution of stable systems to less than 25 per cent. Our results also suggest that the large fraction of observed single-planet systems does not necessarily imply any dichotomy in the architecture of planetary systems. Finally, we use the low abundance of resonances in Kepler data to argue that, in reality, the survival of resonant chains happens likely only in ~5 per cent of the cases. This leads to a mystery: in our simulations only 50-60 per cent of resonant chains became unstable, whereas at least 75 per cent (and probably 90-95 per cent) must be unstable to match observations.
Laboratoire d'astrophysique de Bordeaux Univ. Bordeaux CNRS B18N, allée Geoffroy Saint-Hilaire
UNESP Univ. Estadual Paulista Grupo de Dinâmica Orbital and Planetologia
Division of Theoretical Astronomy National Astronomical Observatory of Japan, 2-21-1, Osawa
Laboratoire Lagrange UMR7293 Université Côe d'Azur CNRS Observatoire de la Côe d'Azur, Boulevard de l'Observatoire
Lund Observatory Department of Astronomy and Theoretical Physics Lund University, Box 43
IAS Institut d'Astrophysique Spatiale Université Paris Sud, Bâtiment 121
UNESP Univ. Estadual Paulista Grupo de Dinâmica Orbital and Planetologia
