Confirmation of bistable stellar differential rotation profiles
arXiv:1401.2981 · doi:10.1051/0004-6361/201423412
Abstract
(abridged) Context: Solar-like differential rotation is characterized by a rapidly rotating equator and slower poles. However, theoretical models and numerical simulations can result in a slower equator and faster poles when the rotation is slow. Aims: We study the critical rotational influence under which differential rotation flips from solar-like (fast equator, slow poles) to an anti-solar one (slow equator, fast poles). We estimate the non-diffusive ( effect) and diffusive (turbulent viscosity) contributions to the Reynolds stress. Methods: We present the results of three-dimensional numerical simulations of mildly turbulent convection in spherical wedge geometry. Here we apply a fully compressible setup which would suffer from a prohibitive time step constraint if the real solar luminosity was used. We regulate the convective velocities by varying the amount of heat transported by thermal conduction, turbulent diffusion, and resolved convection. Results: Increasing the efficiency of resolved convection leads to a reduction of the rotational influence on the flow and a sharp transition from solar-like to anti-solar differential rotation for Coriolis numbers around 1.3. We confirm the recent finding of a large-scale flow bistability: contrasted with running the models from an initial condition with unprescribed differential rotation, the initialization of the model with certain kind of rotation profile sustains the solution over a wider parameter range. Conclusions: Our results may have implications for real stars that start their lives as rapid rotators implying solar-like rotation in the early main-sequence evolution. As they slow down, they might be able to retain solar-like rotation for lower Coriolis numbers before switching to anti-solar rotation. This could partially explain the puzzling findings of anti-solar rotation profiles for models in the solar parameter regime.
11 pages, 10 figures, published in Astronomy & Astrophysics
References in corpus (12)
- Magnetic field generation in fully convective rotating spheres
- Solar differential rotation and meridional flow: The role of a subadiabatic tachocline for the Taylor-Proudman balance
- A global cloud map of the nearest known brown dwarf
- From solar-like to anti-solar differential rotation in cool stars
- Global helioseismic evidence for a deeply penetrating Solar meridional flow consisting of multiple flow cells
- Reynolds stress and heat flux in spherical shell convection
- High-resolution calculations of the solar global convection with the reduced speed of sound technique: I. The structure of the convection and the magnetic field without the rotation
- Meridional Flow in the Solar Convection Zone I: Measurements from GONG Data
- Effect of the radiative background flux in convection
- Angular momentum transport in convectively unstable shear flows
- On global solar dynamo simulations
- Differential rotation and meridional circulation in global models of solar convection
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- On differential rotation and overshooting in solar-like stars
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- High-resolution calculation of the solar global convection with the reduced speed of sound technique: II. Near surface shear layer with the rotation
- Multiple dynamo modes as a mechanism for long-term solar activity variations
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- Powering Stellar Magnetism: Energy Transfers in Cyclic Dynamos of Sun-like Stars
- The Emergence of Solar Supergranulation as a Natural Consequence of Rotationally-Constrained Interior Convection
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- Transition from axi- to nonaxisymmetric dynamo modes in spherical convection models of solar-like stars
- On the cause of solar-like equatorward migration in global convective dynamo simulations
- Efficient small-scale dynamo in solar convection zone
- On the sensitivity of magnetic cycles in global simulations of solar-like stars
- Turbulent transport coefficients in spherical wedge dynamo simulations of solar-like stars
- Velocity Amplitudes in Global Convection Simulations: The Role of the Prandtl Number and Near-Surface Driving
- Generation solar-like differential rotation
- Impacts of stellar evolution and dynamics on the habitable zone: The role of rotation and magnetic activity
- Dynamo cycles in global convection simulations of solar-like stars
- Convection-driven spherical shell dynamos at varying Prandtl numbers
- Influence of a coronal envelope as a free boundary to global convective dynamo simulations
- Evolution of star-planet systems under magnetic braking and tidal interaction
- Consequences of high effective Prandtl number on solar differential rotation and convective velocity
- The impact of rotation on turbulent tidal friction in stellar and planetary convective regions
- A method to discriminate solar and antisolar differential rotation in high-precision light curves
- Star-in-a-box simulations of fully convective stars
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- Effects of a subadiabatic layer on convection and dynamos in spherical wedge simulations
- Sensitivity to luminosity, centrifugal force, and boundary conditions in spherical shell convection
- Theory of solar oscillations in the inertial frequency range: Amplitudes of equatorial modes from a nonlinear rotating convection simulation
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- Characterizing the feedback of magnetic field on the differential rotation of solar-like stars
- Dynamo Effects Near The Transition from Solar to Anti-Solar Differential Rotation
- Convective velocity suppression via the enhancement of subadiabatic layer: Role of the effective Prandtl number
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- Stellar dynamos in the transition regime: multiple dynamo modes and anti-solar differential rotation
- Transition from anti-solar to solar-like differential rotation: Dependence on Prandtl number
- The dynamics of Wolf numbers based on nonlinear dynamo with magnetic helicity: comparisons with observations
- Stellar Dynamos with Solar and Anti-solar Differential Rotations: Implications to Magnetic Cycles of Slowly Rotating Stars
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- Solar-like to Antisolar Differential Rotation: A Geometric Interpretation
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- Impact of anti-solar differential rotation in mean-field solar-type dynamos -- Exploring possible magnetic cycles in slowly rotating stars
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- Forward Modeling Helioseismic Signatures of One- and Two-cell Meridional Circulation
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- Origin of eclipsing time variations: Contributions of different modes of the dynamo-generated magnetic field
- Global Turbulent Solar Convection: a Numerical Path Investigating Key Force Balances in the context of the Convective Conundrum
- Small-scale and large-scale dynamos in global convection simulations of solar-like stars
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- Solar-like dynamos and rotational scaling of cycles from star-in-a-box simulations
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