Evolution of O Stars and the WR Connection

  • Peter S. Conti
Part of the International Astronomical Union/Union Astronomique Internationale book series (IAUS, volume 83)

Abstract

The stellar wind mass loss rates of at least some single Of type stars appear to be sufficient to remove much if not all of the hydrogen-rich envelope such that nuclear processed material is observed at the surface. This highly evolved state can then be naturally associated with classic Population I WR stars that have properties of high luminosity for their mass, helium enriched composition, and nitrogen or carbon enhanced abundances. If stellar wind mass loss is the dominant process involved in this evolutionary scenario, then stars with properties intermediate between Of and WR types should exist. The stellar parameters of luminosity, temperature, mass and composition are briefly reviewed for both types. All late WN stars so far observed are relatively luminous like Of stars, and also contain hydrogen. All early WN stars, and WC stars, are relatively faint and contain little or no hydrogen. The late WN stars seem to have the intermediate properties required if a stellar wind is the dominant mass loss mechanism that transforms an Of star to a WR type.

Keywords

Effective Temperature Mass Loss Rate Stellar Wind Monthly Notice Bolometric Correction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Bappu, M.K.V. and Ganesh, K.S.: 1968, Monthly Notices Roy. Astron. Soc. 140, p. 71.Google Scholar
  2. Bappu, M.K.V. and Sahade, J., eds.: 1973, Wolf-Rayet and High Temperature Stars( Dordrecht: D. Reidel ).Google Scholar
  3. Beals, C.S.: 1938, Trans. IAU 6, p. 248.Google Scholar
  4. Bohannan, B.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P. S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  5. Bohannan, B. and Conti, P.S.: 1976, Astrophys. J. 204, p. 797.ADSCrossRefGoogle Scholar
  6. Bracher, K.: 1967, Ph.D. Thesis, Indiana University.Google Scholar
  7. Breysacher, J. and Azzopardi, M.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  8. Castor, J.I. and Van Blerkom, D.: 1970, Astrophys. J. 161, p. 485.ADSCrossRefGoogle Scholar
  9. Conti, P.S.: 1976, Mem. Soc. Roy. Sci. Liege 9, p. 193.Google Scholar
  10. Conti, P.S.: 1978a, Astron. Astrophys. 63, p. 225.ADSGoogle Scholar
  11. Conti, P.S.: 1978a, Astron. Astrophys. 63, p. 225.ADSGoogle Scholar
  12. Conti, P.S. and Burnichon, M.-L.: 1974, Astron. Astrophys. 38, p. 467.ADSGoogle Scholar
  13. Conti, P.S. and Frost, S.A.: 1977, Astrophys. J. 212, p. 728.ADSCrossRefGoogle Scholar
  14. Conti, P.S. and Frost, S.A.: 1977, Astrophys. J. 212, p. 728.ADSCrossRefGoogle Scholar
  15. Cowley, A.P., Hiltner, W.H. and Berry, C.: 1971, Astron. Astrophys. 11, p. 407.ADSGoogle Scholar
  16. Crampton, D.: 1971, Monthly Notices Roy. Astron. Soc. 153, p. 303.Google Scholar
  17. Ganesh, K.S., Bappu, M.K.V. and Natarijan, V.: 1967, Kodaikanal Obs. Bull. #184.Google Scholar
  18. Hiltner, W.A. and Schild, R.E.: 1966, Astrophys. J. 143, p. 770.ADSCrossRefGoogle Scholar
  19. Hutchings, J.B.: 1976, Astrophys. J. 203, p. 438.ADSCrossRefGoogle Scholar
  20. Hutchings, J.B. and Cowley, A.P.: 1976, Astrophys. J. 206, p. 490.ADSCrossRefGoogle Scholar
  21. Leep, E.M.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  22. de Loore, C., De Greve, J.P. and Van Beveren, D.: 1978, Astron. Astrophys. 67, p. 373.ADSGoogle Scholar
  23. Massey, P. and Conti, P.S.: 1977, Astrophys. J. 218, p. 431.ADSCrossRefGoogle Scholar
  24. Massey, P. and Conti, P.S.: 1979, in Mass Loss and Evolution of 0-Type Stars, eds. P.S. Conti and C. de Loore (Dordrecht: D. Reidel).Google Scholar
  25. McClusky, G.E. and Kondo, Y.: 1976, Astrophys. J. 208, p. 760.ADSCrossRefGoogle Scholar
  26. Moffat, A.F.J., Fitzgerald, M.P.M. and Jackson, P.D.: 1977, Astrophys. J. 215, p. 106.ADSCrossRefGoogle Scholar
  27. Moffat, A.F.J., Fitzgerald, M.P.M. and Jackson, P.D.: 1977, Astrophys. J. 215, p. 106.ADSCrossRefGoogle Scholar
  28. Moffat, A.F.J. and Seggewiss, W.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  29. Morton, D.C.: 1969, Astrophys. J. 158, p. 629.ADSCrossRefGoogle Scholar
  30. Morton, D.C.: 1973, in Wolf-Rayet and High Temperature Stars,eds. M.K.V. Bappu and J. Sahade ( Dordrecht: D. Reidel ), pp. 54–56.CrossRefGoogle Scholar
  31. Niemela, V.S.: 1976, Astrophys. Space Sci. 45, p. 191.ADSCrossRefGoogle Scholar
  32. Niemela, V.S.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  33. Niemela, V.S. and Sahade, J.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  34. Paczynski, B.: 1971, Ann. Rev. Astron. Astrophys. 9, p. 183.ADSCrossRefGoogle Scholar
  35. Paczynski, B.: 1973, in Wolf-Rayet and High Temperature Stars,eds. M.K.V. Bappu and J. Sahade ( Dordrecht: D. Reidel ), pp. 143–152.CrossRefGoogle Scholar
  36. Seggewiss, W.: 1974, Astron. Astrophys. 31, p. 211.ADSGoogle Scholar
  37. Seggewiss, W.: 1974, Astron. Astrophys. 31, p. 211.ADSGoogle Scholar
  38. Slettebak, A., ed.: 1976, Be and Shell Stars( Dordrecht: D. Reidel ).Google Scholar
  39. Smith, L.F.: 1968a, Monthly Notices Roy. Astron. Soc. 138, p. 109.Google Scholar
  40. Smith, L.F.: 1968b, Monthly Notices Roy. Astron. Soc. 140, p. 409.Google Scholar
  41. Smith, L.F.: 1973, in Wolf-Rayet and High Temperature Stars,eds. M.K.V. Bappu and J. Sahade ( Dordrecht: D. Reidel ), pp. 15–35.CrossRefGoogle Scholar
  42. Smith, L.F. and Kuhi, L.V.: 1970, Astrophys. J. 162, p. 535.ADSCrossRefGoogle Scholar
  43. Snow, T.P.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar
  44. Stempien, K.: 1970, Acta Astron. 20, p. 117.ADSGoogle Scholar
  45. Struve, O., Sahade, J., Huang, S.-S. and Zebergs, V.: 1958, Astrophys. J. 128, p. 328.ADSCrossRefGoogle Scholar
  46. Underhill, A.B.: 1968, Ann. Rev. Astron. Astrophys. 6, p. 39.ADSCrossRefGoogle Scholar
  47. Underhill, A.B.: 1973, in Wolf-Rayet and High Temperature Stars,eds. M.K.V. Bappu and J. Sahade ( Dordrecht: D. Reidel ), pp. 237–253.CrossRefGoogle Scholar
  48. Walborn, N.R.: 1974, Astrophys. J. 189, p. 269.ADSCrossRefGoogle Scholar
  49. Willis, A.J. and Wilson, R.: 1978, Monthly Notices Roy. Astron. Soc. 182, p. 559.Google Scholar
  50. Willis, A.J. and Wilson, R.: 1979, in Mass Loss and Evolution of 0-Type Stars,eds. P.S. Conti and C. de Loore ( Dordrecht: D. Reidel).Google Scholar

Copyright information

© International Astronomical Union 1979

Authors and Affiliations

  • Peter S. Conti
    • 1
    • 2
  1. 1.Joint Institute for Laboratory AstrophysicsUniversity of Colorado and National Bureau of StandardsBoulderUSA
  2. 2.Department of Astro-GeophysicsUniversity of ColoradoBoulderUSA

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