Hostname: page-component-848d4c4894-v5vhk Total loading time: 0 Render date: 2024-06-20T09:23:34.481Z Has data issue: false hasContentIssue false
  • English
  • Français

G117-B15A: How is it Evolving?

Published online by Cambridge University Press:  12 April 2016

S.O. Kepler ,
G. Vauclair ,
R.E. Nather ,
D.E. Winget  and
E.L. Robinson
S.O. Kepler
Affiliation:
Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Brazil
G. Vauclair
Affiliation:
Observatoire Midi-PyreneesFrance
R.E. Nather
Affiliation:
McDonald Observatory and Department of AstronomyThe University of Texasat AustinU.S.A.
D.E. Winget
Affiliation:
McDonald Observatory and Department of AstronomyThe University of Texasat AustinU.S.A.
E.L. Robinson
Affiliation:
McDonald Observatory and Department of AstronomyThe University of Texasat AustinU.S.A.

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 measurement of the rate of change of period with time for the g-mode pulsations in ZZ Ceti stars is a direct measurement of the cooling timescale for a DA white dwarf, which in turn can give a totally independent measurement of the age of the galactic disk. Using asteroseismology, we have obtained a rate of change of the period of the dominant pulsation in the light curve of the ZZ Ceti star G117-B15A of dP/dt = (12.5 ± 5.5) × 10−15s/s, equivalent to a timescale for period change of P/P = (5.5 ± 2.4) × 108 yr, which is consistent with the theoretical value for the cooling timescale of a DA white dwarf around 11,000 K.

Type
Research Article
Information
International Astronomical Union Colloquium , Volume 114: White Dwarfs , 1989 , pp. 341 - 345
Copyright
Copyright © Springer-Verlag 1989

References

Brassard, P., Wesemael, F., and Fontaine, G. 1987, in Proceedings of the IAU Colloquium 95, The Second Conference on Faint Blue Stars, ed. Philip, A.G.D., Hayes, D.S., and Liebert, J.W., (L.Davis Press, Schenectady), p. 669. Google Scholar
Dziembowski, W. 1977, Acta Astron., 27, 203.Google Scholar
Eggen, O.J., and Greenstein, J.L. 1965, Ap. J., 141, 183.Google Scholar
Fontaine, G., McGraw, J.T., Dearborn, D.S.P., Gustafson, J., and Lacombe, P. 1982, Ap. J., 258, 651.CrossRefGoogle Scholar
Greenstein, J.L. 1982, Ap. J., 258, 661.CrossRefGoogle Scholar
Kepler, S.O. 1984, Ap. J., 286, 314.CrossRefGoogle Scholar
Kepler, S.O., Robinson, E.L., Nather, R.E., and McGraw, J.T. 1982, Ap. J., 254, 676.Google Scholar
Nather, R.E. 1973, Vistas in Astronomy, 15, 91.Google Scholar
Robinson, E.L., and Kepler, S.O. 1980, Spa. Sci. Rev., 27, 613.Google Scholar
Robinson, E.L., Kepler, S.O., and Nather, R.E. 1982, Ap. J., 259, 219.Google Scholar
Wesemael, F., Lamontagne, R., and Fontaine, G. 1986, Astron. J., 91, 1376.Google Scholar
Winget, D.E. 1981, Ph.D. Thesis, University of Rochester.Google Scholar
Winget, D.E. 1988, in Proceedings of IAU Symposium 123, Advances in Helio- and Asteroseismology, ed. Cristensen-Dalsgaard, J. and Frandsen, S., (D. Reidel, Dordrecht), p. 305. Google Scholar
Winget, D.E., Hansen, C.J., Liebert, J., van Horn, H.M., Fontaine, G., Nather, R.E., Kepler, S.O., and Lamb, D.Q. 1987, Ap. J., 315, L77.CrossRefGoogle Scholar
Winget, D.E., Kepler, S.O., Robinson, E.L., Nather, R.E., and O’Donoghue, D. 1985, Ap. J., 292, 606 Google Scholar
Winget, D.E., and van Horn, H.M. 1987, in Proceedings of the IAU Colloquium 95, The Second Conference on Faint Blue Stars, ed. Philip, A.G.D., Hayes, D.S., and Liebert, J.W., (L. Davis Press, Schenectady), p. 363. Google Scholar
Winget, D.E., van Horn, H.M., Tassoul, M., Hansen, C.J., Fontaine, G., and Carrol, B.W. 1982, Ap. J., 252, L65.CrossRefGoogle Scholar