The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. I. Results from 19 OB Associations in the Magellanic Clouds

  title={The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. I. Results from 19 OB Associations in the Magellanic Clouds},
  author={Philip Massey and E. Waterhouse and Kathleen DeGioia-Eastwood},
  journal={The Astronomical Journal},
We combine new CCD UBV photometry and spectroscopy with those from the literature to investigate 19 Magellanic Cloud OB associations that contain Wolf-Rayet (W-R) and other types of evolved, massive stars. Our spectroscopy reveals a wealth of newly identified interesting objects, including early O-type supergiants, a high-mass, double-lined binary in the SMC, and, in the LMC, a newly confirmed luminous blue variable (LBV; R85), a newly discovered W-R star (Sk -69 degrees 194), and a newly found… 

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