Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-20T07:40:33.109Z Has data issue: false hasContentIssue false
  • English
  • Français

Observations of Magnetic Fields in B Stars

Published online by Cambridge University Press:  26 May 2016

David A. Bohlender
David A. Bohlender*
Affiliation:
Canada-France-Hawaii Telescope Corporation PO Box 1597 Kamuela, Hawaii USA 96743

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Globally ordered magnetic fields are known to exist in non-degenerate stars with spectral types between approximately F0 and B2. Among the B stars, and in order of increasing effective temperature, these include the Bp Si stars, helium-weak stars, and the helium-strong stars. These rather remarkable objects present us with an excellent opportunity to quantitatively examine the possible effects of magnetic fields on the photospheres, winds, and circumstellar environments of hot stars. In this paper we review some of the observations of the magnetic fields and field geometries of magnetic B stars, and also briefly discuss the success of attempts to measure magnetic fields in hotter OB and Be stars. We point out some of the interesting observational similarities of the helium-weak and helium-strong stars to Be and other hot stars, including their spectroscopic and photometric variability, variable winds as demonstrated by the UV resonance lines of C IV and Si IV, and their non-thermal radio emission. Continuing work also suggests that a considerable fraction of the rapidly rotating magnetic helium-peculiar stars are in fact variable Be and Be shell stars.

Type
2. Magnetic Fields
Information
Symposium - International Astronomical Union , Volume 162: Pulsation, Rotation and Mass Loss in Early-Type Stars , 1994 , pp. 155 - 166
Copyright
Copyright © Kluwer 1994 

References

Angel, J.R.P. and Landstreet, J.D.: 1970, Astrophys. J. Let. 160, 147.CrossRefGoogle Scholar
Babcock, H.W.: 1947, Astrophys. J. 105, 105.Google Scholar
Babcock, H.W.: 1949, Astrophys. J. 110, 126.Google Scholar
Babcock, H.W.: 1951, Astrophys. J. 114, 1.CrossRefGoogle Scholar
Barker, P.K.: 1986, in Slettebak, A. Snow, T.P., eds., IAU Colloquium 92, The Physics of Be Stars , Cambridge Univ. Press: Cambridge, 38.Google Scholar
Bohlender, D.A.: 1988, PhD Thesis, Univ. Western Ontario: Canada.Google Scholar
Bohlender, D.A.: 1989, Astrophys. J. 346, 459.Google Scholar
Bohlender, D.A., Brown, D.N., Landstreet, J.D., and Thompson, I.B.: 1987, Astrophys. J. 323, 325.Google Scholar
Bohlender, D.A. and Landstreet, J.D.: 1990a, Astrophys. J. 358, 274.Google Scholar
Bohlender, D.A. and Landstreet, J.D.: 1990b, Astrophys. J. Let. 358, 25.Google Scholar
Bohlender, D.A. and Landstreet, J.D.: 1994, in preparation.Google Scholar
Bolton, C.T., Fullerton, A.W., Bohlender, D.A., Landstreet, J.D. and Gies, D.R.: 1986, in Slettebak, A. and Snow, T.P., eds., IAU Colloquium 92, The Physics of Be Stars , Cambridge Univ. Press: Cambridge, 82.Google Scholar
Borra, E.F., Landstreet, J.D. and Thompson, I.B.: 1983, Astrophys. J. Suppl. 53, 151.Google Scholar
Gray, D.F.: 1988, Lectures on Spectral-Line Analysis: F, G, and K Stars , The Publisher: Arva, Ontario., 6–1.Google Scholar
Harmanec, P.: 1984, Bull. Astron. Inst. Czechosl. , 35, 193.Google Scholar
Henrichs, H.F., Bauer, F., Hill, G.M., Kaper, L., Nichols-Bohlin, J.S. and Veen, P.M.: 1993 in IAU Colloquium 139, New Perspectives on Stellar Pulsation and Pulsating Variable Stars , in press.Google Scholar
Kaper, L., Henrichs, H.F., Ando, H., Bjorkman, K., Fullerton, A.W., Gies, D.R., Hirata, R., Kambe, E., McDavid, D. and Nichols, J.S.: 1994, Astron. Astrophys. submitted.Google Scholar
Landstreet, J.D.: 1980, Astron. J. 85, 611.CrossRefGoogle Scholar
Landstreet, J.D.: 1992, Astron. Astrophys. Rev. 4, 35.Google Scholar
Landstreet, J.D., Barker, P.K., Bohlender, D.A. and Jewison, M.S.: 1989, Astrophys. J. 344, 876.Google Scholar
Linsky, J.L., Drake, S.A. and Bastian, T.S.: 1992, Astrophys. J. 393, 341.Google Scholar
Mathys, G.: 1988, Astron. Astrophys. 189, 179.Google Scholar
Mathys, G.: 1989, Fund. of Cosmic Physics , 13, 143.Google Scholar
Mathys, G.: 1991, Astron. Astrophys. Suppl. 89, 121.Google Scholar
Saar, S.H.: 1990, in Stenflo, J.O., ed., Solar Photosphere: Structure, Convection, and Magnetic Fields , Kluwer: Dordrecht, 427.Google Scholar
Shore, S.N. and Brown, D.N.: 1990, Astrophys. J. 365, 665.Google Scholar
Shore, S.N., Brown, D.N., Sonneborn, G., Landstreet, J.D. and Bohlender, D.A.: 1990, Astrophys. J. 348, 242.Google Scholar
Thompson, I.B. and Landstreet, J.D.: 1985, Astrophys. J. Let. 289, 9.Google Scholar
Walborn, N.R.: 1982, Publ. Astr. Soc. Pacific 94, 322.Google Scholar