Proximity of exoplanets to first-order mean-motion resonances
C Charalambous et al. (2022)
- Published
- Jun 9, 2022
- Journal
- Monthly Notices of the Royal Astronomical Society · Vol. 514 · No. 3
- DOI
- 10.1093/mnras/stac1554
At a GlanceAI
Shows how planet–disc migration naturally produces observed period-ratio offsets near first-order mean-motion resonances.
SummaryAI
Adjacent exoplanet pairs cluster near first-order mean-motion resonances, but typically sit slightly wide of the exact commensurability, and this work explains how that offset can arise during disc-driven migration. By exploring how disc and planet properties affect resonant capture, it finds the offset evolves in time as planets migrate along the apsidal corotation resonance family and grows for higher planet masses and stronger eccentricity damping. For Earth to super-Earth masses, an eccentricity-dependent damping prescription can reproduce observed offsets via a feedback that increases the departure from nominal resonance. For giant planets, a simpler disc-interaction parametrization matches observed offsets when eccentricity damping is low to moderate, with predicted eccentricities also consistent with data.
Method SnapshotAI
Dynamical modeling of two-planet resonant migration under type-I and type-II disc-driven migration prescriptions.
BackgroundAI
Celestial mechanics of mean-motion resonances plus basic planet–disc migration and eccentricity damping concepts.