Improving the asymptotic approximations of higher-order radial oscillations in stars

  • P. Smeyers
  • E. Ruymaekers
Part II Physical Processes in Modelling the Sun
Part of the Lecture Notes in Physics book series (LNP, volume 367)


Since the initial work of Ledoux (1962) on the asymptotic representation of higher-order radial oscillation modes, it has been customary to use the square of the angular frequency as the large parameter in the governing second-order differential equation. In the present investigation, the introduction of a different large parameter is shown to improve the accuracy of the first and second asymptotic approximations of the eigenfrequencies of the radial oscillation modes, for the equilibrium sphere with uniform mass density and the polytropes with index n = 2 and n = 3. The definition of the new large parameter is based on the use of the second-order differential equation in the divergence of the radial displacement.


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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • P. Smeyers
    • 1
  • E. Ruymaekers
    • 2
  1. 1.Astronomisch InstituutKatholieke Universiteit LeuvenBelgium
  2. 2.Research Assistant of the National Fund for Scientific ResearchBelgium

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