Early-type stars in the core of the young open cluster Westerlund 2 ⋆⋆⋆

  title={Early-type stars in the core of the young open cluster Westerlund 2 ⋆⋆⋆},
  author={Gregor Rauw and Jean Manfroid and Eric Gosset and Ya{\"e}l Naz{\'e} and Hugues Sana and Micha{\"e}l De Becker and C'edric Foellmi and Anthony F. J. Moffat},
  journal={Astronomy and Astrophysics},
Aims. The properties of the early-type stars in the core of the Westerlund 2 cluster are examined in order to establish a link bet ween the cluster and the very massive Wolf-Rayet binary WR 20a as well as the Hii complex RCW 49. Methods. Photometric monitoring as well as spectroscopic observations of Westerlund 2 are used to search for light variability and to establish the spectral types of the early-type stars in the c luster core. Results. The first light curves of the eclipsing binary WR… Expand

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