Time, spatial, and spectral resolution of the Hα line-formation region of Deneb and Rigel with the VEGA/CHARA interferometer

  title={Time, spatial, and spectral resolution of the H$\alpha$ line-formation region of Deneb and Rigel with the VEGA/CHARA interferometer},
  author={Olivier Chesneau and Luc Dessart and Denis Mourard and Philippe B{\'e}rio and Christian Buil and Daniel Bonneau and Marcelo Borges Fernandes and J. M. Clausse and Omar Delaa and Aur{\'e}lie Marcotto and Anthony Meilland and F. Millour and Nicolas Nardetto and K. Perraut and Alain Roussel and Alain Spang and P. Stee and I. Tallon-Bosc 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},
BA-type supergiants are amongst the most optically-bright stars. They are observable in extragalactic environments, hence potential accurate distance indicators. Emission activity in the Halpha line of the BA supergiants Rigel (B8Ia) and Deneb (A2Ia) is indicative of presence of localized time-dependent mass ejections. Here, we employ optical interferometry to study the Halpha line-formation region in these stellar environments. High spatial- (0.001 arcsec) and spectral- (R=30 000) resolution… 
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