On the Coupling between Helium Settling and Rotation-Induced Mixing in Stellar Radiative Zones: I- Analytical Approach

Abstract

In the presence of rotation-induced mixing, element diffusion still occurs in stellar radiative zones, although at a slower rate than in the case of a complete stability of the stellar gas. As a consequence, helium settling leads to vertical $\mu$-gradients which, due to the meridional circulation, turn into horizontal fluctuations. Up to now, the feed-back effect of this process on the rotation-induced mixing was currently neglected in the computations of abundance variations in stellar surfaces, or artificially reduced. Here we analyse its consequences and derive an approximate analytical solution in a quasi-stationary case. We also discuss the relative importance of the various physical effects which influence the meridional circulation velocity. In a second paper (Théado and Vauclair 2002a), we will present a complete 2D numerical simulation of this process while a third paper (Théado and Vauclair 2002b) will be devoted to special applications to Pop I stars.

7 printed pages, 1 figure. ApJ, in press (April 20, 2003)

References in corpus (2)

• On the coupling between helium settling and rotation-induced mixing in stellar radiative zones : II- Numerical approach
• On the Coupling between Helium Settling and Rotation-Induced Mixing in Stellar Radiative Zones: II- Application to light elements in population I main-sequence stars

Cited by in corpus (10)

• Solar structure and evolution
• Metal-rich accretion and thermohaline instabilities in exoplanets-host stars: consequences on the light elements abundances
• Magnetic field and wind of Kappa Ceti: towards the planetary habitability of the young Sun when life arose on Earth
• Age and mass of solar twins constrained by lithium abundance
• Lithium abundance and rotation of seismic solar analogues - Solar and stellar connection from Kepler and Hermes observations
• Solar twins in M67 : Evolutionary status and lithium abundance
• Mass effect on the lithium abundance evolution of open clusters: Hyades, NGC 752, and M67
• Updated Toulouse solar models including the diffusion-circulation coupling and the effect of $\mu$-gradients
• On the coupling between helium settling and rotation-induced mixing in stellar radiative zones : II- Numerical approach
• On the Coupling between Helium Settling and Rotation-Induced Mixing in Stellar Radiative Zones: II- Application to light elements in population I main-sequence stars