Free inertial modes in differentially rotating convective envelopes of low-mass stars : numerical exploration

TL;DR

This paper investigates how latitudinal differential rotation affects free inertial modes in low-mass stars' convective envelopes, revealing new mode families and highlighting the significance of critical layers for tidal dissipation.

Contribution

It introduces the impact of differential rotation on inertial modes and identifies new mode families, advancing understanding of stellar tidal dissipation mechanisms.

Findings

Differential rotation alters inertial mode properties.

Critical layers may significantly influence tidal dissipation.

New families of inertial modes are identified.

Abstract

Tidally-excited inertial waves in stellar convective regions are a key mechanism for tidal dissipation in stars and therefore the evolution of close-in binary or planetary systems. As a first step, we explore here the impact of latitudinal differential rotation on the properties of free inertial modes and identify the different families of modes. We show that they differ from the case of solid-body rotation. Using an analytical approach as well as numerical calculations, we conclude that critical layers (where the Doppler-shifted frequency vanishes) could play a very important role for tidal dissipation.