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arXiv · 1710.08663

Towards a better understanding of tidal dissipation at corotation layers in differentially rotating stars and planets

A. Astoul·S. Mathis·C. Baruteau·Q. André
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Abstract

Star-planet tidal interactions play a significant role in the dynamical evolution of close-in planetary systems. We investigate the propagation and dissipation of tidal inertial waves in a stellar/planetary convective region. We take into account a latitudinal differential rotation for the background flow, similar to what is observed in the envelope of low-mass stars like the Sun. Previous works have shown that differential rotation significantly alters the propagation and dissipation properties of inertial waves. In particular, when the Doppler-shifted tidal frequency vanishes in the fluid, a critical layer forms where tidal dissipation can be greatly enhanced. Our present work develops a local analytic model to better understand the propagation and dissipation properties of tidally forced inertial waves at critical layers.

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A. Astoul, S. Mathis, C. Baruteau, Q. André. 2017-10-24. Towards a better understanding of tidal dissipation at corotation layers in differentially rotating stars and planets. https://arxiv.org/abs/1710.08663

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