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Stellar Winds and Spindown in Solar Type Stars

Published online by Cambridge University Press:  04 August 2017

I.W. Roxburgh
I.W. Roxburgh*
Affiliation:
Department of Applied Mathematics Queen Mary College, University of London Mile End Road, London E1 4NS

Abstract

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The angular momentum loss produced by stellar winds is reviewed and a simple model of angular momentum loss with multipole fields is presented in which the field is potential when the flow speed is less than the Alfvén speed, and radial when greater than the Alfvén speed. The simpler the magnetic geometry, the larger is the angular momentum loss rate. This result is used to explain the rotational discontinuity across the Vaughan-Preston gap as being due to a sudden increase in angular momentum loss when the dynamo field switches from a quadropole to a dipole geometry.

The evolution of the internal rotation of stars as a result of surface angular momentum loss is considered. In the absence of a magnetic field, differential rotation can drive instabilities which then transport angular momentum out from the interior down the angular velocity gradient. Other instabilities such as that caused by the build up of 3He can also transport angular momentum outwards. If angular momentum is transported by such weak turbulence, it also makes the star more homogeneous than standard evolutionary models and lowers the predicted value of the solar neutrino flux.

The recent results on rotational splitting of solar oscillations are considered: these suggest that the inside of the sun is spinning faster than the surface and are compatible with models in which angular momentum is transported by mild turbulence. But data is scarce — and in such circumstances the speculations of the theorist must be viewed with caution!

Type
V. Stellar Winds and Spindown in Late — Type Stars
Information
Symposium - International Astronomical Union , Volume 102: Solar and Stellar Magnetic Fields: Origins and Coronal Effects , 1983 , pp. 449 - 460
Copyright
Copyright © Reidel 1983 

References

Altschuler, M.D. and Newkirk, G.: 1969, Solar Phys. 9, p. 131.CrossRefGoogle Scholar
Biermann, P.: 1968, Diplomarbeit, Göttingen.Google Scholar
Claverie, A., Isaak, G.R., McLeod, C.P., and van der Ray, H.B.: 1981, Nature 293, p. 443.Google Scholar
Christensen-Dalsgaard, J., Dilke, F.W.W., and Gough, D.O.: 1974, Monthly Notices Roy. Astron. Soc. 169, p. 429.Google Scholar
Davis, R.: 1978, Proceedings Conf. on Solar Neutrinos, Brookhaven Nat. Lab. BNL 50879, Vol. I, p. 1.Google Scholar
Dicke, R.H.: 1972, Astrophys. J. 171, p. 331.Google Scholar
Dilke, F.W.W. and Gough, D.O.: 1972, Nature 240, p. 262.Google Scholar
Durney, B.R.: 1972, in “Solar Wind”, eds. Sonnett, C.P., Coleman, P.J., and Wilcox, J.M., NASA SP 308, p. 282.Google Scholar
Durney, B.R. and Pneuman, G.W.: 1975, Solar Phys. 40, p. 461.Google Scholar
Eddington, A.S.: 1926, “Internal Constitution of the Stars”, Cambridge University Press, p. 393.Google Scholar
Endal, A. and Sofia, S.: 1981, Astrophys. J. 243, p. 625.Google Scholar
Endler, F.: 1971, Mitt. Astron. Ges. 30, p. 136.Google Scholar
Fricke, K.: 1968, Z. Astrophys. 68, p. 317.Google Scholar
Goldreich, P. and Schubert, G.: 1967, Astrophys. J. 150, p. 571.Google Scholar
Gough, D.O.: 1982, Nature 298, p. 334.Google Scholar
Hill, H.: 1982, Irish Astron. J. (in press).Google Scholar
H⊘iland, E.: 1941, Avhandl. utgilt Norske Vidensk. Akad. Oslo, I Mat.-naturv. k1. No. 11.Google Scholar
Knobloch, E. and Spruit, H.C.: 1982, Astron. Astrophys. (in press).Google Scholar
Mestel, L.: 1968, Monthly Notices Roy. Astron. Soc. 138, p. 359.Google Scholar
Parker, E.N.: 1958, Astrophys. J. 128, p. 664.Google Scholar
Pneuman, G.W. and Kopp, R.A.: 1971, Solar Phys. 18, p. 258.Google Scholar
Robertson, B.R.: 1983, Solar Phys. (in press).Google Scholar
Rood, R.T.: 1978, Proceedings Conf. on Solar Neutrinos, Brookhaven Nat. Lab. BNL 50879, Vol. I, p. 175.Google Scholar
Rowse, D.P. and Roxburgh, I.W.: 1981, Solar Phys. 74, p. 165.Google Scholar
Roxburgh, I.W.: 1975, Mem. Soc. Roy. Sci. Liège, 6e Série 8, p. 69.Google Scholar
Roxburgh, I.W.: 1976, in “Basic Mechanisms of Solar Activity”, eds. Bumba, V. and Kleczek, J., Dordrecht: D. Reidel Publ. Co., p. 453.Google Scholar
Roxburgh, I.W.: 1978, Proceedings Conf. on Solar Neutrinos, Brookhaven Nat. Lab. BNL 50879, Vol. I, p. 207.Google Scholar
Roxburgh, I.W.: 1978, in “Pleins Feux sur la Physique Solaire”, Centre Nat. de la Recherche Scientifique, No. 282, p. 21.Google Scholar
Roxburgh, I.W.: 1978, Astron. Astrophys. 65, p. 281.Google Scholar
Roxburgh, I.W.: 1982, (to be published).Google Scholar
Roxburgh, I.W.: 1983, (to be published).Google Scholar
Schatten, K.H.: 1970, Solar Phys. 15, p. 499.Google Scholar
Schatzman, E. and Maeder, A.: 1981, Astron. Astrophys. 96, p. 1.Google Scholar
Skumanich, A.: 1972, Astrophys. J. 171, p. 565.Google Scholar
Weber, E.J. and Davis, L. Jr.: 1967, Astrophys. J. 148, p. 217.Google Scholar
Zahn, J.P.: 1975, Mem. Soc. Roy. Sci. Liège, 6e Série 8, p. 31.Google Scholar