Cartography of the Sun and the Stars pp 101-125 | Cite as

# Physical Processes Leading to Surface Inhomogeneities: The Case of Rotation

## Abstract

In this lecture I discuss the bulk surface heterogeneity of rotating stars, namely gravity darkening. I especially detail the derivation of the *ω*-model of Espinosa Lara and Rieutord (Astron Astrophys 533:A43, 2011), which gives the gravity darkening in early-type stars. I also discuss the problem of deriving gravity darkening in stars owning a convective envelope and in those that are members of a binary system.

## Keywords

Effective Temperature Differential Rotation Stellar Surface Roche Lobe Turbulent Convection## Notes

### Acknowledgements

I am grateful to the organizers of the Besançon school for their invitation, and the opportunity to present in more details the recent work I did with Francisco Espinosa Lara on gravity darkening. This school triggered many stimulating discussions that helped me deepen this subject. Finally, I would like to stress that this work owes much to Francisco who had the original idea of the *ω*-model.

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