Hostname: page-component-84b7d79bbc-g5fl4 Total loading time: 0 Render date: 2024-07-26T00:15:10.028Z Has data issue: false hasContentIssue false

Magnetic Braking in Cataclysmic and Low-Mass X-Ray Binaries*

Published online by Cambridge University Press:  12 April 2016

O. Vilhu*
Affiliation:
Nordita, Copenhagen, Denmark

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.

The chromospheric-coronal emission of lower Main-Sequence single and binary stars can be correlated with an activity parameter of type R = g(B-V)P-1 where P is the rotation or orbital period and g(B-V) a function of the color resembling the convective turnover time. Observations indicate that the active region area coverage filling factor grows as R2, and the whole stellar surface becomes filled with closed loop structures at R ≂ 3. A braking formula is proposed (Equation 4) to include all periods (0.d1 ≲ R ≳ 30d) and spectral types F-M. On the basis of this equation, the mass transfer rates in compact binaries (driven by the gradual loss of orbital angular momentum) are discussed. It is concluded that the magnetic braking has good chances of being that mechanism which drives the mass transfer in cataclysmic variables and galactic bulge X-ray sources.

Type
Research Article
Copyright
Copyright © Reidel 1984

Footnotes

**

On leave from Observatory and Astrophysics Laboratory, University of Helsinki.

*

Paper presented at the Lembang-Bamberg IAU Colloquium No. 80 on ‘Double Stars: Physical Properties and Generic Relations, held at Indonesia, 3-7 June, 1983.

References

Durney, B. R. and Latour, J.: 1978, Geophys. Astrophys. Fluid Dyn. 9, 241.CrossRefGoogle Scholar
Catalano, S. and Marilli, E.: 1983, Astron. Astrophys. 121, 190.Google Scholar
Frazier, E. N.: 1970, Solar Phys. 14, 89.Google Scholar
Gilman, P. A.: 1980, in Gray, D. and Linsky, J. (eds.), Stellar Turbulence, Springer, Berlin, p. 19.Google Scholar
Joss, P. C. and Rappaport, S.: 1979, Astron. Astrophys. 71, 217.Google Scholar
Middelkoop, F.: 1981, Astron. Astrophys. 101, 295.Google Scholar
Noyes, R. W.: 1983, in Stendo, J. O. (ed.), ‘Solar and Stellar Magnetic Fields: Origins and Coronal Effects', IAU Symp. 102, 133.Google Scholar
Rappaport, S., Joss, P. C., and Webbink, R.: 1982, Astrophys. J. 254, 616.CrossRefGoogle Scholar
Rucinski, S. M.: 1983 (preprint).Google Scholar
Skumanich, A.: 1972, Astrophys. J. 171, 565.Google Scholar
Skumanich, A. and Eddy, J.: 1981, in Bonnet, R. M. and Dupree, A. K. (eds.), Solar Phenomena in Stars and Stellar Systems, D. Reidei Pubi. Co., Dordrecht, Holland, p. 349.Google Scholar
Spruit, H. C. and Ritter, H.: 1983, Astron. Astrophys. 142, 267.Google Scholar
Tutukov, A. V.: 1983, (preprint).Google Scholar
Tutukov, A. V. and Yungelson, L. R.: 1979, Acta Astron. 25, 665.Google Scholar
Verbunt, F. and Zwaan, C.: 1981, Astron. Astrophys. 100, L7.Google Scholar
Vilhu, O.: 1982, Astron. Astrophys. 109, 17.Google Scholar
Vilhu, O.: 1983. NORDITA preprint 83/21 (Astron. Astrophys., in press).Google Scholar