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arXiv · 2103.15843

Tilting Planets During Planet Scattering

Gongjie Li
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Abstract

Observational constraints on planet spin-axis has recently become possible, and revealed a system that favors a large spin-axis misalignment, a low stellar spin-orbit misalignment and a high eccentricity. To explain the origin of such systems, we propose a mechanism that could tilt the planet spin-axis during planet-planet scattering, which are natural outcomes of in-situ formation and disk migration. Specifically, we show that spin-orbit resonances could occur for a short time period during the scattering processes, and excite the misalignment of the planet spin-axis. This typically leads to planets with large spin-misalignment and a wide range of eccentricities and inclinations.

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Gongjie Li. 2021-03-29. Tilting Planets During Planet Scattering. https://doi.org/10.3847/2041-8213%2Fac0620

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