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arXiv · 1709.05784

The fate of close-in planets: tidal or magnetic migration?

A. Strugarek·E. Bolmont·S. Mathis·A. S. Brun·V. Réville·F. Gallet·C. Charbonnel
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Abstract

Planets in close-in orbits interact magnetically and tidally with their host stars. These interactions lead to a net torque that makes close-in planets migrate inward or outward depending on their orbital distance. We compare systematically the strength of magnetic and tidal torques for typical observed star-planet systems (T-Tauri & hot Jupiter, M dwarf & Earth-like planet, K star & hot Jupiter) based on state-of-the-art scaling-laws. We find that depending on the characteristics of the system, tidal or magnetic effects can dominate. For very close-in planets, we find that both torques can make a planet migrate on a timescale as small as 10 to 100 thousands of years. Both effects thus have to be taken into account when predicting the evolution of compact systems.

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A. Strugarek, E. Bolmont, S. Mathis, A. S. Brun, V. Réville, F. Gallet, C. Charbonnel. 2017-09-18. The fate of close-in planets: tidal or magnetic migration?. https://doi.org/10.3847/2041-8213/aa8d70

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