UMR 5672

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What's new under the Sun ?

Allan Sacha Brun (LDEE Cea Saclay)
When Jan 26, 2015
from 11:00 AM to 12:30 PM
Where Centre Blaise Pascal
Attendees Allan Sacha Brun
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We will discuss our recent progress to model in 3-D the solar global interior dynamics using the anelastic spherical harmonic (ASH) code. We will show that the nonlinear mechanical and thermal coupling between a turbulent convective envelope and a stable radiative interior yields realistic rotation profile, with a differentially rotating convective envelope and a tachocline of shear at its base. We will further investigate the excitation and propagation of internal waves in the  deep radiative interior. Thanks to the use of a realistic seismically calibrated stratification (i.e solar-like Brunt-Väisälä frequency),   we observe a large spectrum of internal waves in our simulation. These modes are excited by the continuous pummeling of convective plumes.  When comparing with asymptotic formulations and an adiabatic oscillation code we find a good overall agreement and confirm that those waves are indeed gravity waves. We then discuss their properties and visibility at the surface and compare with recent observations. 
 

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