Sub-milliarcsecond precision spectro-astrometry of Be stars

  title={Sub-milliarcsecond precision spectro-astrometry of Be stars},
  author={Rene Dick Oudmaijer and Andrew M. Parr and Deborah Baines and John M. Porter},
  journal={Astronomy and Astrophysics},
Context. The origin of the disks around Be stars is still not known. Further progress requires a proper parametrization of their structure, both spatially and kinematically. This is challenging as the disks are very small. Aims. Here we assess whether a novel method is capable of providing these data. Methods. We obtained spectro-astrometry around the Pa β line of two bright Be stars, α  Col and ζ  Tau, to search for disk signatures. The data, with a pixel-to-pixel precision of the centroid… 

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