On the nature of the galactic early-B hypergiants

  title={On the nature of the galactic early-B hypergiants},
  author={J. Simon Clark and Francisco Najarro and I. Negueruela and Benedict W. Ritchie and Miguel Alejandro Urbaneja and Ian D. Howarth},
  journal={Astronomy and Astrophysics},
Aims. Despite their importance to a number of astrophysical fields , the lifecycles of very massive stars are still poorly define d. In order to address this shortcoming, we present a detailed quantitative study of the physical properties of four early-B hypergiants (BHGs) of spectral type B1-4 Ia + ; Cyg OB2 #12, � 1 Sco, HD 190603 and BP Cru. These are combined with an analysis of their long-term spectroscopic and photometric behaviour in order to determine their evolutionary status. Methods… 
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