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Rotation and Line Broadening in OBA Stars

Published online by Cambridge University Press:  26 May 2016

Ian D. Howarth
Ian D. Howarth*
Affiliation:
Dept. Physics & Astronomy, UCL, Gower St., London WC1E 6BT, UK

Abstract

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Observational v sin i line-width measurements for OBA stars are summarized, and the relationship of these measurements to ve sin i, the true projected equatorial rotation velocity, reviewed. In general, ve sin i ≥ v sin i for Be Stars, while ve sin i ≤ v sin i for O-type stars. The implications are that (i) it is probable that Be Stars are closer to their critical rotation velocities than is generally supposed (rendering plausible a range of new physical mechanisms for the Be phenomenon); and (ii) some non-rotational macroscopic line broadening (‘turbulence’) occurs in the atmospheres of O stars (and BA supergiants). Physical interpretations of this ‘turbulence’ are considered.

Type
Session 1 Observations of Rotating Stars
Information
Symposium - International Astronomical Union , Volume 215: Stellar Rotation , 2004 , pp. 33 - 42
Copyright
Copyright © Astronomical Society of the Pacific 2004 

References

Abt, H.A., Morrell, N.I. 1995, ApJS 99, 135 CrossRefGoogle Scholar
Abt, H.A., Levato, H., Grosso, M. 2002, ApJ 573, 359 Google Scholar
Balona, L. 1974, MNRAS 78, 51 Google Scholar
Chauville, J., Zorec, J., et al. 2001, A&A 378, 861 Google Scholar
Collins, G.W. 1974, ApJ 191, 157 CrossRefGoogle Scholar
Collins, G.W., Truax, R.J. 1995, ApJ 439, 860 Google Scholar
Conti, P., Ebbets, D. 1977, ApJ 213, 438 Google Scholar
Ebbets, D. 1979, ApJ 227, 510 CrossRefGoogle Scholar
Fliegner, J., Langer, N., Venn, K.A. 1996, A&A 308, L13 Google Scholar
Gray, D. 1977, ApJ 211, 198 Google Scholar
Gray, D. 1992: The observation and analysis of stellar photospheres (CUP)Google Scholar
Halbedel, E.M. 1996, PASP 108, 833 Google Scholar
Herrero, A., Kudritzki, R.-P., et al. 1992, A&A 261, 209 Google Scholar
Howarth, I.D., Siebert, K.W., Hussain, G.A.J., Prinja, R.K. 1997, MNRAS 284, 265 Google Scholar
Howarth, I.D., Smith, K.C. 2001, MNRAS 327, 353 Google Scholar
Kudritzki, R.P. 1992, A&A 266, 395 Google Scholar
Maeder, A. 2003, these proceedings Google Scholar
McErlean, N.D., Lennon, D.J., Dufton, P.L., 1998, A&A 329, 613 Google Scholar
Owocki, S. 2003, these proceedings Google Scholar
Penny, L.R. 1996, ApJ 463, 737 Google Scholar
Rosseland, S. 1928, MNRAS 89, 49 CrossRefGoogle Scholar
Royer, F., et al. 2002, A&A 381, 105 & 393, 897 Google Scholar
Ryans, R.S.I., Dufton, P.L., et al. 2002, MNRAS 336, 577 Google Scholar
Schönberner, D., Herrero, A., et al. 1988, A&A 197, 208 Google Scholar
Slettebak, A. 1956, ApJ 124, 173 Google Scholar
Slettebak, A. 1966, ApJ 145, 126 Google Scholar
Slettebak, A. 1982, ApJS 50, 55 (S82) CrossRefGoogle Scholar
Slettebak, A., Collins, G.W., et al. 1975, ApJS 29, 137 (SC75) Google Scholar
Smith, K.C., Howarth, I.D. 1998, MNRAS 299, 1146 CrossRefGoogle Scholar
Steele, I.A., Negueruela, I., Clark, J.S. 1999, A&A 137, 147 Google Scholar
Stoeckley, T.R. 1968, MNRAS 140, 141 CrossRefGoogle Scholar
Struve, O. 1931, ApJ 73, 94 Google Scholar
Struve, O. 1952, PASP 64, 117 Google Scholar
Townsend, R.H.D. 2003, these proceedings Google Scholar
Venn, K.A. 1999, ApJ 518, 405 Google Scholar
Verdugo, E., Talavera, A., Gómez de Castro, A.I. 1999, A&A 346, 819 Google Scholar
Villamariz, M.R., Herrero, A. 2000, A&A 357, 597 Google Scholar
Walborn, N.R. 1976, ApJ 205, 419 Google Scholar
Wolff, S.C., Edwards, S., Preston, G.W. 1982, ApJ 252, 322 Google Scholar
Zahn, J.-P. 1992, A&A 265, 115 Google Scholar