Perturbations and Stability of Rotating Stars - Part Three - Perturbation Theory for Eigenvalues

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

10

Scientific paper

The normal mode problem for perturbations of a perfect-fluid rotating star is a non-selfadjoint eigenvalue problem. To study the changes in the eigenfrequencies when the operators in the problem change slightly, this paper develops the appropriate lowest-order perturbation theory and discusses two important cases. In the first case the perturbing operator is the inclusion of a `secular' effect, such as viscosity or radiation reaction. Here the main interest is in unperturbed eigenfrequencies that are dynamically stable, and the perturbed frequencies are analytic functions of the perturbation parameter. Explicit formulae are derived for use in numerical calculations of secular effects in stars. The second case is the study of the onset of dynamical instability itself. Here the perturbing operator is a slight change in the structure of the star. It is found that instability sets in only through eigenvalues which have Jordan chains, and the perturbation theory is non-analytic. It is shown that stable modes do not have Jordan chains, and the marginally stable modes have, in the generic case, chains of length 1. This gives a fairly complete characterization of the manner in which instability arises along a sequence of stars.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Perturbations and Stability of Rotating Stars - Part Three - Perturbation Theory for Eigenvalues does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Perturbations and Stability of Rotating Stars - Part Three - Perturbation Theory for Eigenvalues, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Perturbations and Stability of Rotating Stars - Part Three - Perturbation Theory for Eigenvalues will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-881972

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.