Core-envelope coupling of gravito-inertial waves in pre-main-sequence solar-type stars

Abstract

After the recent detection of solar equatorial Rossby waves, a renewed interest has been brought to the study of gravito-inertial waves propagating in the convective envelope of solar-type stars. In particular, the ability that some of these envelope gravito-inertial modes have to couple with the ones trapped in the radiative interior might open new windows to probe the deep-layer dynamics of solar-type stars. The possibility for such a coupling to occur is particularly favoured in pre-main sequence (PMS) solar-type stars. Indeed, due to the contraction of the protostellar object, they are able to reach large rotation frequencies before nuclear reactions are ignited and magnetic braking becomes the driving mechanism for their rotational evolution. In this work, we therefore study the coupling between the envelope inertial waves and the radiative interior g modes in PMS stars, focusing on the case of prograde dipolar modes. We consider the case of 0.5 Msun and 1 Msun PMS models, each with three different scenarios of rotational evolution. We show that, for stars that have formed with a sufficient amount of angular momentum, this coupling can occur in frequency ranges that are accessible to space-borne photometry, creating inertial dips in the period spacing pattern. With an asymptotic analysis we characterise the shape of these inertial dips to show that they depend on rotation and on the stiffness of the convective-radiative interface.

11 pages, 7 figures. Accepted for publication in A&A

References in corpus (27)

• Modules for Experiments in Stellar Astrophysics (MESA)
• The Transiting Exoplanet Survey Satellite
• The K2 Mission: Characterization and Early results
• GYRE: An open-source stellar oscillation code based on a new Magnus Multiple Shooting Scheme
• The Mass-Dependence of Angular Momentum Evolution in Sun-Like Stars
• Improved angular momentum evolution model for solar-like stars II. Exploring the mass dependence
• Global-scale equatorial Rossby waves as an essential component of solar internal dynamics
• Internal Gravity Wave Excitation by Turbulent Convection
• Stochastic excitation of nonradial modes II. Are solar asymptotic gravity modes detectable?
• Theoretical seismology in 3D : nonlinear simulations of internal gravity waves in solar-like stars
• Rotation of the convective core in $\gamma$ Dor stars measured by dips in period spacings of g modes coupled with inertial modes
• Rotation rate of the solar core as a key constraint to magnetic angular momentum transport in stellar interiors
• First evidence of inertial modes in $\gamma$ Doradus stars: The core rotation revealed
• Generation of internal gravity waves by penetrative convection
• Impact of rotation on stochastic excitation of gravity and gravito-inertial waves in stars
• Theory of solar oscillations in the inertial frequency range: Amplitudes of equatorial modes from a nonlinear rotating convection simulation
• A model of rotating convection in stellar and planetary interiors: II -- gravito-inertial wave generation
• Pulsational instability of pre-main sequence models from accreting protostars. I. Constraining the input physics for accretion with spectroscopic parameters and stellar pulsations
• Asteroseismology of the dip structure in period-spacings of rapidly rotating gamma Doradus stars caused by the coupling between core and envelope oscillations
• Stochastic excitation of internal gravity waves in rotating late F-type stars: A 3D simulation approach
• Interaction of solar inertial modes with turbulent convection. A 2D model for the excitation of linearly stable modes
• The Pre-main Sequence: Challenges and Prospects for Asteroseismology
• Overstable Convective Modes in a Polytropic Stellar Atmosphere
• Properties of observable mixed inertial and gravito-inertial modes in γ Doradus stars
• Constraining differential rotation in gamma Doradus stars from inertial dips properties
• Excitation of Inertial Modes in 3D Simulations of Rotating Convection in Planets and Stars
• Exploring the probing power of gamma-Dor's inertial dip for core magnetism: case of a toroidal field

Cited by in corpus (1)

• From core to envelope: revealing the deep dynamics of stars with two convective zones