Chromosphere of K giant stars. Geometrical extent and spatial structure detection

  title={Chromosphere of K giant stars. Geometrical extent and spatial structure detection},
  author={Philippe B{\'e}rio and Thibault Merle and F. Th{\'e}venin and Daniel Bonneau and Denis Mourard and Olivier Chesneau and Omar Delaa and Roxanne Ligi and Nicolas Nardetto and K. Perraut and Bernard Pichon and P. Stee and I. Tallon-Bosc and J. M. Clausse and Alain Spang and Harold A. Mcalister and Theo A. ten Brummelaar and Judit Sturmann and Laszlo Sturmann and Nils H. Turner and Christopher D. Farrington and P. J. Goldfinger},
  journal={Astronomy and Astrophysics},
Context. Interferometers provide accurate diameter measurements of stars by analyzing both the continuum and the lines formed in photospheres and chromospheres. Tests of the geometrical extent of the chromospheres are therefore possible by comparing the estimated radius in the continuum of the photosphere and the estimated radii in chromospheric lines. Aims. We aim to constrain the geometrical extent of the chromosphere of non-binary K giant stars and detect any spatial structures in the… 
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