Space Science Reviews

, Volume 66, Issue 1–4, pp 395–400 | Cite as

The mass and helium discrepancy in massive stars: The case Vela X-1

  • D. Vanbeveren
  • A. Herrero
  • D. Kunze
  • M. Van Kerkwijk
Structure and Evolution of Massive Stars


A NLTE-analysis is presented of high S/N spectra of the optical component of the standard massive X-ray binary Vela X-1. In combination with the orbital parameters we conclude that the optical star is highly helium enriched and is significantly overluminous compared to standard evolutionary tracks of massive accretion stars. We then propose a new accretion model able to explain these features.

Key words

Stars:Atmospheres Stars:Evolution Stars:Binaries 


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  1. Benson, R.S.: 1970a,Ph. D. Thesis, Univ. of California: Berkeley.Google Scholar
  2. Benson, R.S.: 1970b,Bull. Am. Astron. Soc. 2, 295.Google Scholar
  3. de Jager, C., Nieuwenhuyzen, H. and van der Hucht, K.: 1988,Astron. Astrophys. Suppl. 72, 259Google Scholar
  4. Herrero, A., Kudritzki, R.P., Vilchez, J.M., Kunze, D., Butler, K. and Haser, S.: 1992,Astron. Astrophys. 261, 209.Google Scholar
  5. Hiltner, W.A., Werner, J. and Osmer, P.S.: 1972,Ap. J. Letters 175, L19.Google Scholar
  6. Khruzina, T.S. and Cherepashchuk, A.M.: 1986,Sov. Astron. 30, 422.Google Scholar
  7. Maeder, A.: 1990,Astron. Astrophys. Suppl. 84, 139.Google Scholar
  8. Rappaport, S. and Joss, P.C.: 1983, ‘’ in W.H.G. Lewin, E.P.J. van den Heuvel, ed(s).,Accretion Driven Stellar X-ray Sources, Cambridge Univ. Press: Cambridge.Google Scholar
  9. Joss, P.C. and Rappaport, S.: 1984,Ann. Rev. Astron. Astrophys. 22, 537.Google Scholar
  10. Zuiderwijk, E.J. and van den Heuvel, E.P.J.: 1974,Astron. Astrophys. 35, 353.Google Scholar

Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • D. Vanbeveren
    • 1
  • A. Herrero
    • 2
  • D. Kunze
    • 3
  • M. Van Kerkwijk
    • 4
  1. 1.Dept. of PhysicsV.U.B.BrusselsBelgium
  2. 2.Instituto de Astrofisica de CanariasLa Laguna, TenerifeSpain
  3. 3.Universitats-SternwarteMunchen 80Germany
  4. 4.Astrophysical InstituteUniversity of AmsterdamAmsterdamThe Netherlands

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