The coupling between internal waves and shear-induced turbulence in stellar radiation zones: the critical layer

Abstract

Internal gravity waves (hereafter IGWs) are known as one of the candidates for explaining the angular velocity profile in the Sun and in solar-type main-sequence and evolved stars, due to their role in the transport of angular momentum. Our bringing concerns critical layers, a process poorly explored in stellar physics, defined as the location where the local relative frequency of a given wave to the rotational frequency of the fluid tends to zero (i.e that corresponds to co-rotation resonances). IGW propagate through stably-stratified radiative regions, where they extract or deposit angular momentum through two processes: radiative and viscous dampings and critical layers. Our goal is to obtain a complete picture of the effects of this latters. First, we expose a mathematical resolution of the equation of propagation for IGWs in adiabatic and non-adiabatic cases near critical layers. Then, the use of a dynamical stellar evolution code, which treats the secular transport of angular momentum, allows us to apply these results to the case of a solar-like star.The analysis reveals two cases depending on the value of the Richardson number at critical layers: a stable one, where IGWs are attenuated as they pass through a critical level, and an unstable turbulent case where they can be reflected/transmitted by the critical level with a coefficient larger than one. Such over-reflection/transmission can have strong implications on our vision of angular momentum transport in stellar interiors. This paper highlights the existence of two regimes defining the interaction between an IGW and a critical layer. An application exposes the effect of the first regime, showing a strengthening of the damping of the wave. Moreover, this work opens new ways concerning the coupling between IGWs and shear instabilities in stellar interiors.

17 pages, 8 figures

References in corpus (28)

• Low Temperature Opacities
• Fast core rotation in red-giant stars revealed by gravity-dominated mixed modes
• A fossil origin for the magnetic fields of A-stars and white dwarfs
• Stellar evolution with rotation VII: Low metallicity models and the blue to red supergiant ratio in the SMC
• Seismic evidence for a rapidly rotating core in a lower-giant-branch star observed with Kepler
• Tidal dissipation in rotating solar-type stars
• Thermohaline instability and rotation-induced mixing. III - Grid of stellar models and asymptotic asteroseismic quantities from the pre-main sequence up to the AGB for low- and intermediate-mass stars at various metallicities
• Hydrodynamical stellar models including rotation, internal gravity waves and atomic diffusion. I. Formalism and tests on Pop I dwarfs
• On shear-induced turbulence in rotating stars
• Transport and mixing in the radiation zones of rotating stars: I-Hydrodynamical processes
• Internal Gravity Waves Modulate the Apparent Misalignment of Exoplanets around Hot Stars
• Magnetic confinement of the solar tachocline
• Transport and mixing in the radiation zones of rotating stars II. Axisymmetric magnetic field
• Diagnoses to unravel secular hydrodynamical processes in rotating main sequence stars
• Internal Gravity Wave Excitation by Turbulent Convection
• Neon Abundances in B-Stars of the Orion Association: Solving the Solar Model Problem?
• Stellar rotation: Evidence for a large horizontal turbulence and its effects on evolution
• Magnetic confinement of the solar tachocline: II. Coupling to a convection zone
• Stochastic excitation of nonradial modes II. Are solar asymptotic gravity modes detectable?
• Three-dimensional simulations of internal wave breaking and the fate of planets around solar-type stars
• Gravity Waves in the Sun
• Gravity modes in rapidly rotating stars. Limits of perturbative methods
• Solar neutrinos, helioseismology and the solar internal dynamics
• Spectrum and amplitudes of internal gravity waves excited by penetrative convection in solar-type stars
• Dynamics of the solar tachocline II: the stratified case
• Turbulent transport in radiative zones of stars
• Reflection and Ducting of Gravity Waves Inside the Sun
• On over-reflection and generation of Gravito-Alfven waves in solar-type stars

Cited by in corpus (26)

• Angular momentum transport by heat-driven g-modes in slowly pulsating B stars
• Tidal dissipation in evolving low-mass and solar-type stars with predictions for planetary orbital decay
• Theoretical seismology in 3D : nonlinear simulations of internal gravity waves in solar-like stars
• Can plume-induced internal gravity waves regulate the core rotation of subgiant stars?
• Magnetic signatures on mixed-mode frequencies. I. An axisymmetric fossil field inside the core of red giants
• Internal rotation of 13 low-mass low-luminosity red giants in the Kepler field
• Characterizing the propagation of gravity waves in 3D nonlinear simulations of solar-like stars
• Asymptotic theory of gravity modes in rotating stars. I. Ray dynamics
• Dynamics of Mixed Convective--Stably-Stratified Fluids
• Angular momentum transport by stochastically excited oscillations in rapidly rotating massive stars
• A model of rotating convection in stellar and planetary interiors: II -- gravito-inertial wave generation
• Detecting deep axisymmetric toroidal magnetic fields in stars. The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field
• The effects of nonlinearities on tidal flows in the convective envelopes of rotating stars and planets in exoplanetary systems
• The complex interplay between tidal inertial waves and zonal flows in differentially rotating stellar and planetary convective regions I. Free waves
• Three-Dimensional Simulations of Massive Stars: II. Age Dependence
• Theoretical investigation of the occurrence of tidally excited oscillations in massive eccentric binary systems
• Baroclinic Instability in Stellar Radiation Zones
• How do tidal waves interact with convective vortices in rapidly-rotating planets and stars?
• Pulsation-driven mean zonal and meridional flows in rotating massive stars
• Nonlinear internal waves breaking in stellar radiation zones. Parametrisation for the transport of angular momentum: bridging geophysical to stellar fluid dynamics
• The robustness of inferred envelope and core rotation rates of red-giant stars from asteroseismology
• Mixing by Internal Gravity Waves in Stars: Assessing Numerical Simulations Against Theory
• Impact of near-degeneracy effects on linear rotational inversions for red-giant stars
• Understanding hydrodynamical wave-driven shear mixing in stellar radiation zones. Looking in the mirror of the dyapicnal oceanic mixing
• Co-existence of Internal Gravity Waves and Tayler-Spruit Magnetic Fields in the Radiative Core of Low-mass Stars
• Observational imprints of tidal internal gravity wave dissipation in star-planet systems