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Variations in Luminous Blue Variables

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Book cover Instabilities in Luminous Early Type Stars

Part of the book series: Astrophysics and Space Science Library ((ASSL,volume 136))

Abstract

The photometric and spectroscopic variability of Luminous Blue Variables is discussed and compared with predictions. The photometric variations occur on all timescales from weeks to centuries. There are three kinds of photometric variations: large variations with △v ≳ 3m, due to large eruptions; moderate variations of △v ~ 1m, due to shell ejections; and microvariations with △v ~ 0.1m, probably due to pulsation. If the large eruptions are recurrent, the time of recurrence is of the order of centuries. The moderate variations occur on timescales of months to decades. During shell ejections the bolometric luminosity remains constant but the temperature of the pseudo-photosphere decreases and the radius increases. The observed variations of V, B-V and Teff of S Dor and AG Car agree reasonably well with the predicted effects of variable mass loss. The semiperiods of the microvariations are about twice as large as for normal supergiants of the same L and Teff and 4 to 20 times larger than the fundamental mode for radial pulsation.

There are three kinds of spectral variations: changes of the spectral type; large variations of the shapes of the line profiles; small variations of absorption components superimposed on the overall line profiles. The first two variations are due to large variations in the mass loss, and are accompanied by moderate photometric variations of △v ~ 1m. After an increased mass loss, the spectrum often shows forbidden emission lines formed in the ejected shell. The small variations of the absorption components of P Cygni indicate recurrent ejections of shells or blobs on a timescale of about 2 months with a shell mass of about 10-5 M⨀.

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References

  • Appenzeller, I.: 1972, Publ. Astron. Soc. Japan 24, 483.

    ADS  Google Scholar 

  • Appenzeller, I.: 1987, These proceedings.

    Google Scholar 

  • Appenzeller, I., Wolf, B.: 1982,

    Google Scholar 

  • Bensammer, S., Gaudenzi, S., Rossi, C., Johnson, H.M., Thé, P.S., Zuiderwijk, E.J., Viotti, R.: 1981 in Proc. IAU Coll. 59, eds. C. Chiosi and R. Stalio, p. 67.

    Google Scholar 

  • Bond, H.E., Landolt, A.U.: 1970, Publ. Astron. Soc. Pacific 82, 313.

    Article  ADS  Google Scholar 

  • Burki, G.: 1978, Astron. Astrophys. 65, 357.

    Article  ADS  Google Scholar 

  • Conti, P.S.: 1984, in Observational Tests of the Stellar Evolution Theory, eds. A. Maeder and A. Renzini, ( Dordrecht: Reidel ) p. 233.

    Google Scholar 

  • Davidson, K.: 1987, These proceedings.

    Google Scholar 

  • Davidson, K.: 1987, Astrophys. J. (in press).

    Google Scholar 

  • de Groot, M.: 1969, Bull. Astron. Inst. Netherlands 20, 235.

    Google Scholar 

  • de Jager, C.: 1980, The Brightest Stars, ( Dordrecht: Reidel ) p. 296.

    Book  Google Scholar 

  • Duemmler, R., Markova, N.: 1987 (preprint).

    Google Scholar 

  • Feast, M.W., Thackeray, A.D., Wesselink, A.J.: 1960, Monthly Notices Roy. Astron. Soc. 121, 354.

    ADS  Google Scholar 

  • Gaposchkin, S.: 1943, Astrophys J. 97, 166.

    Article  ADS  Google Scholar 

  • Hayes, D.P.: 1985, Astrophys. J. 289, 726.

    Article  ADS  Google Scholar 

  • Hubble, E., Sandage, A.: 1953, Astrophys. J. 118, 353.

    Article  ADS  Google Scholar 

  • Humphreys, R.M., Blaha, C., D’Odorico, S., Gull, T.R., Benvenuti, P.: 1984, Astrophys. J. 278, 124.

    Article  ADS  Google Scholar 

  • Humphreys, R.M., Davidson, K.: 1979, Astrophys. J. 232, 409.

    Article  ADS  Google Scholar 

  • Kenyon, S.J., Gallagher, J.S.: 1985, Astrophys. J. 290, 542.

    Article  ADS  Google Scholar 

  • Lamers, H.J.G.L.M.: 1986, in Luminous Stars in Associations and Galaxies, eds. C. de Loore etal. ( Dordrecht: Reidel ) p. 157.

    Google Scholar 

  • Lamers, H.J.G.L.M., de Groot, M., Cassatella, A.: 1983, Astron. Astrophys. 128, 299.

    ADS  Google Scholar 

  • Lamers, H.J.G.L.M., Korevaar, P., Cassatella, A.: 1985, Astron. Astrophys. 149, 29.

    ADS  Google Scholar 

  • Leitherer, C., Appenzeller, I., Klare, G., Lamers, H.J.G.L.M., Stahl, O., Waters, L.B.F.M., Wolf, B.: 1985, Astron. Astrophys. 153, 168.

    ADS  Google Scholar 

  • Lovey, D., Maeder, A., Noëls, A., Gabriel, M.: 1984, Astron. Astrophys. 133, 307.

    ADS  Google Scholar 

  • Maeder, A.: 1980, Astron. Astrophys. 90, 311.

    ADS  Google Scholar 

  • Maeder, A.: 1983, Astron. Astrophys. 120, 113.

    Google Scholar 

  • Maeder, A., Rufener, F.: 1972, Astron. Astrophys. 162, L3.

    Google Scholar 

  • Markova, N.: 1986, Astron. Astrophys.

    Google Scholar 

  • Markova, N., Kolka, I.: 1984, Astrofiz. 20, 250.

    ADS  Google Scholar 

  • Markova, N., Luud, L.: 1983, Publ. Tartu Astrophys. Obs. 32, 55.

    Google Scholar 

  • Martini, A.: 1969, Astron. Astrophys. 3, 443.

    ADS  Google Scholar 

  • Mayall, M.W.: 1969, J. Roy. Astron. Soc. Canada 63, 221.

    ADS  Google Scholar 

  • Rosino, L., Bianchini, A.: 1973, Astron. Astrophys. 22, 453.

    ADS  Google Scholar 

  • Schmidt-Kaler, T.: 1982, in Landolt-Börnstein, New Series, Group VI, Vol. 2b; eds. K. Schaifers and H.H. Voigt ( Berlin: Springer ) p. 15.

    Google Scholar 

  • Stahl, O., Wolf, B.: 1982, Astron. Astrophys. 110, 272.

    ADS  Google Scholar 

  • Stahl, O., Wolf, B., Klare, G., Cassatella, A., Krautter, J., Persi, P., Ferrari-Toniolo, M.: 1983, Astron. Astrophys. 127, 49.

    ADS  Google Scholar 

  • Stahl, O., Wolf, B., Zickgraf, F.J., Bastian, U., de Groot, M.J.H., Leitherer, C.: 1983, Astron. Astrophys. 120, 287.

    ADS  Google Scholar 

  • Thackeray, A.D.: 1956, Vistas in Astron. 2, 1380.

    Article  ADS  Google Scholar 

  • van Genderen, A.M.: 1979, Astron. Astrophys. Suppl. 38, 381.

    Google Scholar 

  • van Genderen, A.M.: 1985, Astron. Astrophys. 151, 349.

    ADS  Google Scholar 

  • van Genderen, A.M.: 1986a, Astron. Astrophys. 157, 163.

    ADS  Google Scholar 

  • van Genderen, A.M.: 1986b, Private Communications.

    Google Scholar 

  • van Genderen, A.M., Steemers, W.J.G., Feldbrugge, P.T.M., Groot, M., Damen, E., van den Boogaart, A.K.: 1985, Astron. Astrophys. 153, 163.

    ADS  Google Scholar 

  • van Genderen, A.M., Thé, P.S.: 1985, Space Sci. Rev. 39, 317.

    Google Scholar 

  • van Gent, R.H., Lamers, H.J.G.L.M.: 1986, Astron. Astrophys. 158, 335.

    ADS  Google Scholar 

  • Viotti, R.: 1969, Astrophys. Space Sci. 5, 323.

    Google Scholar 

  • Viotti, R., Altamora, A., Barylak, M., Cassatella, A., Gilmozzi, R., Rossi, C.: 1984 in Future of UV Astronomy based on Six Years of IUE Research, NASA Conf. Publ. 2349, p. 231.

    Google Scholar 

  • Walborn, N.R.: 1977, Astrophys. J. 215, 53.

    Article  ADS  Google Scholar 

  • Waters, L.B.F.M., Wesselius, P.R.: 1986, Astron. Astrophys. 155, 104.

    ADS  Google Scholar 

  • Wendker, H.J.: 1982, Astron. Astrophys. 116, L5.

    ADS  Google Scholar 

  • White, R.L., Becker, R.H.: 1982, Astrophys. J. 262, 657.

    Article  ADS  Google Scholar 

  • Whitelock, P.A., Carter, B.S., Roberts, G., Whittet, D.C.B., Baines,D.W.T.: 1983, Mon. Not. Roy. Astron. Soc. 205, 577.

    ADS  Google Scholar 

  • Wolf, B.: 1975, Astron. Astrophys. 41, 471.

    ADS  Google Scholar 

  • Wolf, B., Stahl, O.: 1982, Astron. Astrophys. 112, 111.

    ADS  Google Scholar 

  • Wolf, B., Stahl, 0., de Groot, M.J.H., Sterken, C.: 1981a, Astron. Astrophys. 99, 351.

    ADS  Google Scholar 

  • Wolf, B., Appenzeller, I., Stahl, O.: 1986b, Astron. Astrophys. 103, 94.

    ADS  Google Scholar 

  • Zinner, E.: 1952, Kleine Veröff. Remeis-Sternwarte Bamberg 1, nr. 7.

    Google Scholar 

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Author information

Authors and Affiliations

  1. SRON Laboratory for Space Research, Beneluxlaan 21, 3527 HS, Utrecht, The Netherlands

    Henny J. G. L. M. Lamers

  2. Sonnenborgh Observatory, Zonnenburg 2, 3512 NL, Utrecht, The Netherlands

    Henny J. G. L. M. Lamers

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  1. Henny J. G. L. M. Lamers
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Editors and Affiliations

  1. Sonnenborgh Observatory and SRON Laboratory for Space Research, Utrecht, The Netherlands

    Henny J. G. L. M. Lamers

  2. Astrophysical Institute, Vrije Universiteit Brussel and Rijksuniversitair Centrum Antwerpen, University of Antwerp, Belgium

    Camiel W. H. De Loore

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© 1987 D. Reidel Publishing Company, Dordrecht, Holland

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Lamers, H.J.G.L.M. (1987). Variations in Luminous Blue Variables. In: Lamers, H.J.G.L.M., De Loore, C.W.H. (eds) Instabilities in Luminous Early Type Stars. Astrophysics and Space Science Library, vol 136. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-3901-1_7

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  • DOI: https://doi.org/10.1007/978-94-009-3901-1_7

  • Publisher Name: Springer, Dordrecht

  • Print ISBN: 978-94-010-8232-7

  • Online ISBN: 978-94-009-3901-1

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