Determination of the masses of the components of the HDE 226868/Cyg X-1 binary system.

  title={Determination of the masses of the components of the HDE 226868/Cyg X-1 binary system.},
  author={Jan M. Ziolkowski},
  journal={Monthly Notices of the Royal Astronomical Society: Letters},
  • J. Ziolkowski
  • Published 6 January 2014
  • Physics
  • Monthly Notices of the Royal Astronomical Society: Letters
Recent determination of the distance to HDE 226868/Cyg X-1 binary system (Reid et al., 2011) and more precise determination of the effective temperature of HDE 226868 (Caballero- Nieves et al., 2009) permit a more accurate estimate of the masses of both components. Using up to date evolutionary models, I obtain a mass range of between 25 to 35 Msun for the mass of the supergiant and between 13 to 23 Msun for the mass of the black hole. Accepting more liberal estimates of uncertainties in both… 

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