Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-23T20:18:18.013Z Has data issue: false hasContentIssue false

The ZZ Ceti Stars and the Rate of Evolution of White Dwarfs

Published online by Cambridge University Press:  12 April 2016

Edward L. Robinson
Affiliation:
Department of Astronomy, McDonald Observatory; University of Texas at Austin
S. O. Kepler
Affiliation:
Department of Astronomy, McDonald Observatory; University of Texas at Austin

Extract

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 importance of the ZZ Ceti stars, and indeed the importance of all pulsating stars, derives from the fact that stellar pulsations probe the interiors of stars, and thus they test directly our models of stellar interiors and stellar evolution. The relative value of stellar pulsations as such a probe depends on, among other factors, the number of pulsation modes simultaneously excited in a star, as each additional mode depends on and constrains the properties of the star in a different way. Judged by this criterion, the pulsations of the ZZ Ceti stars should be unusually valuable because all ZZ Ceti stars are multi-mode variables. For example, among the ZZ Ceti stars with well studied light curves, the one with the fewest modes is R548 (= ZZ Ceti itself) with 4 pulsation modes simultaneously excited (Robinson et al. 1976), while some of the other ZZ Ceti stars can have dozens of pulsation modes simutaneously excited (cf. Robinson 1979).

Type
X. White Dwarf Pulsations
Copyright
Copyright © Reidel 1980

References

Cox, J. P. 1976, Ann. Rev. Astr. and Ap., 14, 247.CrossRefGoogle Scholar
Greenstein, J. L., Boksenberg, A., Carswell, R., and Shortridge, K. 1977 Ap. J., 212, 186.CrossRefGoogle Scholar
Kepler, S. O., Robinson, E. L., Nather, R. E., and McGraw, J. T. 1980, in preparation.Google Scholar
Liebert, J. 1980, Ann. Rev. Astr. and Ap., 18, in press.CrossRefGoogle Scholar
McGraw, J. T. 1979, Ap. J., 229, 203.CrossRefGoogle Scholar
Osaki, Y., and Hansen, C. J. 1973, Ap. J., 185, 277.Google Scholar
Ostriker, J. P., and Tassoul, J. L. 1969, Ap. J., 155, 987.CrossRefGoogle Scholar
Papaloizou, J., and Pringle, J. E. 1978, M.N.R.A.S., 182, 423.Google Scholar
Robinson, E. L. 1979, in White Dwarfs and Variable Degenerate Stars, IAU Coll. No. 53, ed. by Van Horn, H. M. and Weidemann, V. (University of Rochester: New York), p. 343.Google Scholar
Robinson, E. L., Nather, R. E., and McGraw, J. T. 1976, Ap. J., 210, 211.Google Scholar
Robinson, E. L., Stover, R. J., Nather, R. E., and McGraw, J. T. 1978, Ap. J., 220, 614.Google Scholar
Shaviv, G., and Kovetz, A. 1976, Astron. and Ap., 51, 383.Google Scholar
Stover, R. J., Hesser, J. E., Lasker, B. M., Nather, R. E., and Robinson, E. L. 1980, Ap. J., in press.Google Scholar
Unno, W., Osaki, Y., Ando, H., and Shibahashi, H. 1979, Nonradial Oscillations of Stars (University of Tokyo Press), Section 34. 626 Google Scholar