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
(Submitted on 18 Sep 2017)

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.

Comments:    9 pages, 2 figures, 1 table, accepted for publication in The Astrophysical Journal Letters
Subjects:    Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP)
Cite as:    arXiv:1709.05784 [astro-ph.SR] (or arXiv:1709.05784v1 [astro-ph.SR] for this version)
Submission history
From: Antoine Strugarek [view email]
[v1] Mon, 18 Sep 2017 06:21:01 GMT (623kb,D)
https://arxiv.org/abs/1709.05784