Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-27T05:16:13.740Z Has data issue: false hasContentIssue false

R Coronae Borealis Pulsations

Published online by Cambridge University Press:  12 April 2016

David S. King*
Affiliation:
The University of New Mexico, Albuquerque, New Mexico 87131

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 Cepheid-like pulsations of some of the R CrB stars should in principle make it possible to determine their masses and hence to place constraints on possible evolution scenarios. We briefly review the evidence for these pulsations and discuss the problem of how these low-mass, hydrogen-deficient carbon stars could have evolved to their present position in the H-R diagram. Linear and nonlinear pulsation calculations are reviewed. It is found that for these large luminosity to mass ratio (L/M) stars a region of pulsation instability extends considerably hotter than for normal high luminosity Cepheids. The envelopes of these models are so nonadiabatic that the identification of modes becomes very difficult since there is frequently no clearly defined nodal structure. For the most extreme L/M cases it is found that the models are unstable in the sense that they appear on the verge of ejecting the outer layers.

Type
VIII. R Coronae Borealis Pulsations
Copyright
Copyright © Reidel 1980

References

Alexander, J. B., Andrews, P. J., Catchpole, R. M., Feast, M. W., Evans, T. Lloyd, Menzes, J. W., Wisse, P. N. J., and Wisse, M.: 1972, M.N.R.A.S. 158, p. 305.CrossRefGoogle Scholar
Christy, R. F.: 1966, Ap. J. 144, p. 108.Google Scholar
Cogan, B. C.: 1972 (private communications).Google Scholar
Cox, A. N., and Stewart, J. N.: 1965, Ap. J. Suppl. 11, p. 22.Google Scholar
Cox, A. N., and Stewart, J. N.: 1970, Ap. J. Suppl. 19, p. 243.Google Scholar
Danziger, I. J.: 1965, M.N.R.A.S. 130, p. 199.Google Scholar
Dinger, A. C. L.: 1972, M.N.R.A.S. 153, p. 383.CrossRefGoogle Scholar
Feast, M. W.: 1975, in Variable Stars and Stellar Evolution, IAU Symposium No. 67, Eds. Sherwood, V. E., and Plaut, L., D. Reidel, Dordrecht, p. 545.Google Scholar
Feast, M. W., and Glass, I. S.: 1973, M.N.R.A.S. 161, p. 293.Google Scholar
Gough, D. O.: 1972 (private communications).Google Scholar
Huebner, W. F., Merts, A. L., Magee, N. H. Jr., , and Agro, M. F.: 1977, Los Alamos Scientific Laboratory Report No. LA-6760-M.Google Scholar
King, D. S., Wheeler, J. C., Cox, J. P., Cox, A. N., and Hodson, S. W.: 1980, in Nonradial and Nonlinear Stellar Pulsation, eds. Hill, H. A. and Dziembowski, W. A., Springer-Verlag, p. 161.CrossRefGoogle Scholar
Kutter, G. S., and Sparks, W. M.: 1974, Ap. J. 192, p. 447.Google Scholar
Paczyński, B.: 1971, Acta Astr. 21, p. 1.Google Scholar
Schönberner, D.: 1975, Astr. Ap. 44, p. 383.Google Scholar
Schönberner, D.: 1977, Astr. Ap. 57, p. 437.Google Scholar
Schönberner, D.: 1979, Astr. Ap. 79, p. 108.Google Scholar
Smith, R. L., and Rose, W. K.: 1972, Ap. J. 176, p. 395.CrossRefGoogle Scholar
Stellingwerf, R. F.: 1975, Ap. J. 195, p. 441.CrossRefGoogle Scholar
Trimble, V.: 1972, M.N.R.A.S. 156, p. 411.Google Scholar
Trimble, V., and Paczynski, B.: 1973, Astr. Ap. 22, p. 9.Google Scholar
Uus, U.: 1973, Soviet Astr. 17, p. 196.Google Scholar
Warner, B.: 1967, M.N.R.A.S. 137, p. 119.Google Scholar
Wheeler, J. C.: 1978, Ap. J. 225, p. 212.Google Scholar
Wing, R. F., Baumert, J. H., Strom, S. E., and Strom, K. M.: 1972, Publ. Astr. Soc. Pacific 84, p. 646.Google Scholar
Wood, P. R.: 1974, Ap. J. 190, p. 609.Google Scholar
Wood, P. R.: 1976, M.N.R.A.S. 174, p. 531.Google Scholar
Wood, P. R., and Cahn, J. H.: 1977, Ap. J. 211, p. 499.Google Scholar