Unveiling Mira stars behind the molecules - Confirmation of the molecular layer model with narrow band near-infrared interferometry

  title={Unveiling Mira stars behind the molecules - Confirmation of the molecular layer model with narrow band near-infrared interferometry},
  author={Guy Perrin and Stephen T. Ridgway and Bertrand Mennesson and William D. Cotton and Julien Woillez and Tijl Verhoelst and Peter A. Schuller and Vincent Coud{\'e} du Foresto and Wesley A. Traub and Rafael Millan-Gabet and Marc G. Lacasse},
  journal={Astronomy and Astrophysics},
We have observed Mira stars with the FLUOR beamcombiner on the IOTA interferometer in narrow bands around $2.2\,\mu$m wavelength. We find systematically larger diameters in bands contaminated by water vapor and CO. The visibility measurements can be interpreted with a model comprising a photosphere surrounded by a thin spherical molecular layer. The high quality of the fits we obtain demonstrates that this simple model accounts for most of the star's spatial structure. For each star and each… 

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