Abstract
We discuss, in general, the problem of deriving a vibrational stability coefficient of stars in thermal imbalance on the basis of an energy principle.
The damped harmonic oscillator with variable spring ‘constant’ provides a typical illustration of the problem. In fact, for systems with variable parameters (as evolving stars), the vibrational stability coefficients, defined respectively in terms of the behaviour of the small displacement and of the total pulsation energy, are basically different. Davey and Cox's so-called ‘modified’ energy method, proposed in order to recover the small displacement stability coefficient, is also shown to be unsatisfactory.
The use of results obtained in the first two papers by asymptotic methods yields a simple compact general expression for the vibrational stability coefficient relative to the pulsation energy of arbitrary evolving stars. This allows the easy recovery of results obtained by more complicated approaches due to Kato and Unno, Simon and Sastri and Axel and Perkins, valid only in particular cases.
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References
Aizenman, M. L. and Cox, J. P.: 1975,Astrophys. J. 195, 175.
Axel, L. and Perkins, F.: 1971,Astrophys. J. 163, 29.
Bogoliubov, N. N. and Mitropolsky, Y. A.: 1961,Asymptotic Methods in the Theory of Non-linear Oscillations, Gordon and Breach, London.
Cox, J. P. and Giuli, R. T.: 1968,Principles of Stellar Structure, Gordon and Breach, New York.
Cox, J. P., Hansen, C. J., and Davey, W. R.: 1973,Astrophys. J. 182, 883.
Cox, J. P., Davey, W. R., and Aizenman, M. L.: 1974,Astrophys. J. 191, 439.
Davey, W. R. and Cox, J. P.: 1974,Astrophys. J. 189, 113.
Demaret, J.: 1974,Astrophys. Space Sci. 31, 305 (‘I’).
Demaret, J.: 1975a,Astrophys. Space Sci. 33, 189 (‘II’).
Demaret, J.: 1975b, ‘Influence de l'évolution et des corrections de relativité générale sur la stabilité stellaire’, Ph. D. Thesis, University of Liège (unpublished).
Demaret, J. and Perdang, J.: 1976, in preparation.
Eddington, A. S.: 1919,Monthly Notices Roy. Astron. Soc. 79, 2, 177.
Feshchenko, S. F., Shkil', N. I., and Nikolenko, L. D.: 1967,Asymptotic Methods in the Theory of Linear Differential Equations, American Elsevier Publishing Company, New York.
Kato, S. and Unno, W.: 1967,Publ. Astron. Soc. Japan 19, 1.
Ledoux, P.: 1958, in S. Flügge (ed.),Handbuch der Physik, Springer-Verlag,51, 605.
Ledoux, P. and Walraven, Th.: 1958, in S. Flügge (ed.),Handbuch der Physik, Springer-Verlag,51, 353.
Mann, R. A.: 1974,The Classical Dynamics of Particles, Academic Press, New York.
Rosseland, S.: 1949,The Pulsation Theory of Variable Stars, Clarendon Press, Oxford.
Simon, N. R.: 1970,Astrophys. J. 159, 859.
Simon, N. R.: 1971,Astrophys. J. 164, 331.
Simon, N. R. and Sastri, V. R.: 1972,Astron. Astrophys. 21, 39.
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Demaret, J. Vibrational stability of stars in thermal imbalance. Astrophys Space Sci 45, 31–45 (1976). https://doi.org/10.1007/BF00642139
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DOI: https://doi.org/10.1007/BF00642139