Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-23T18:44:05.635Z Has data issue: false hasContentIssue false
  • English
  • Français

A Statistical Treatment of the Stellar Rotational Velocities Which Considers the Break-Up Limit

Published online by Cambridge University Press:  12 April 2016

P. L. Bernacca
P. L. Bernacca*
Affiliation:
Asiago Astrophysical Observatory, University of Padua, Italy

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.

This paper develops a new statistical approach to the study of the axial rotational velocities of the stars, by considering the break-up limit or any upper limit for the equatorial rotational velocities. The main conclusions are as follows: (1) For random orientation of the axis of rotation, the frequency function of the inclination α to the line of sight is not sina, as assumed until now. (2) For stars with the same break-up velocity vb, the distribution of α is given by :

where f(y) is the distribution of the apparent velocities y = v sin α, v being the true rotational velocity. New integral equations governing the frequency function of α, y and v have been derived and the correct procedure to treat observations has been discussed; a simple method is also suggested to get an approximate trend of the distribution of the true velocities directly from the observed histogram. The method of analysis proposed in this paper has been applied to a re-discussion of the rotational behaviour of a group of Be stars.

Type
Part III / Stellar Rotation in Binaries, Clusters, and Special Objects. Statistics of Stellar Rotation
Information
International Astronomical Union Colloquium , Volume 4: Stellar Rotation , 1970 , pp. 227 - 248
Copyright
Copyright © Reidel 1970

References

Chandrasekhar, S. and Munch, G. : 1950, Astrophys. J. 111, 142.Google Scholar
Deeming, T. J. and Walker, G. A. H. : 1967, Nature, February 4, 479.Google Scholar
Huang, S. S.: 1953, Astrophys. J. 118, 285.Google Scholar
Huang, S. S.: 1969, Vistas in Astronomy, vol. 11 (ed. by Beer, A.), Pergamon Press p. 217.Google Scholar
Schild, R. E.: 1966, Astrophys. J. 146, 142.Google Scholar
Shajn, G. and Struve, O. : 1929, Monthly Notices Roy. Astron. Soc. 89, 222.Google Scholar
Slettebak, A. : 1949, Astrophys. J. 110, 498.Google Scholar
Slettebak, A. : 1966a, Astrophys. J. 145, 121.CrossRefGoogle Scholar
Slettebak, A. : 1966b, Astrophys. J. 145, 126.Google Scholar
Trumpler, R. J. and Weaver, H. F.: 1953, Statistical Astronomy, University of California Press, Berkeley and Los Angeles.CrossRefGoogle Scholar