Asymmetries on red giant branch surfaces from CHARA/MIRC optical interferometry

  title={Asymmetries on red giant branch surfaces from CHARA/MIRC optical interferometry},
  author={A. Chiavassa and R. Norris and M. Montarg{\`e}s and R. Ligi and L. Fossati and L. Bigot and F. Baron and P. Kervella and J. Monnier and D. Mourard and N. Nardetto and G. Perrin and G. Schaefer and T. Brummelaar and Z. Magic and R. Collet and M. Asplund},
  journal={Astronomy and Astrophysics},
Context. Red giant branch (RGB) stars are very bright objects in galaxies and are often used as standard candles. Interferometry is the ideal tool to characterize the dynamics and morphology of their atmospheres. Aims. We aim at precisely characterising the surface dynamics of a sample of RGB stars. Methods. We obtained interferometric observations for three RGB stars with the MIRC instrument mounted at the CHARA interferometer. We looked for asymmetries on the stellar surfaces using limb… Expand

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