VLTI/PIONIER images the Achernar disk swell

  title={VLTI/PIONIER images the Achernar disk swell},
  author={Gaetan Dalla Vedova and F. Millour and A. Domiciano de Souza and Romain G. Petrov and Daniel Moser Faes and Alex C. Carciofi and Pierre Kervella and Th. Rivinius},
  journal={Astronomy and Astrophysics},
Context. The mechanism of disk formation around fast-rotating Be stars is not well understood. In particular, it is not clear which mechanisms operate, in addition to fast rotation, to produce the observed variable ejection of matter. The star Achernar is a privileged laboratory to probe these additional mechanisms because it is close, presents B ⇌ Be phase variations on timescales ranging from ~6 yr to ~15 yr, a companion star was discovered around it, and probably presents a polar wind or jet… 

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