Interferometric observations of the supergiant stars α Orionis and α Herculis with FLUOR at IOTA

  title={Interferometric observations of the supergiant stars $\alpha$ Orionis and $\alpha$ Herculis with FLUOR at IOTA},
  author={Guy Perrin and Stephen T. Ridgway and Vincent Coud{\'e} du Foresto and Bertrand Mennesson and Wesley A. Traub and Marc G. Lacasse},
  journal={Astronomy and Astrophysics},
We report the observations in the K band of the red supergiant star α Orionis and of the bright giant star α Herculis with the FLUOR beamcombiner at the IOTA interferometer. The high quality of the data allows us to estimate limb-darkening and derive precise diameters in the K band which combined with bolometric fluxes yield effective temperatures. In the case of Betelgeuse, data collected at high spatial frequency although sparse are compatible with circular symmetry and there is no clear… 

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