Results on the spectrum of R-Modes of slowly rotating relativistic stars

Abstract

The paper considers the spectrum of axial perturbations of slowly uniformly rotating general relativistic stars in the framework of Y. Kojima. In a first step towards a full analysis only the evolution equations are treated but not the constraint. Then it is found that the system is unstable due to a continuum of non real eigenvalues. In addition the resolvent of the associated generator of time evolution is found to have a special structure which was discussed in a previous paper. From this structure it follows the occurrence of a continuous part in the spectrum of oscillations at least if the system is restricted to a finite space as is done in most numerical investigations. Finally, it can be seen that higher order corrections in the rotation frequency can qualitatively influence the spectrum of the oscillations. As a consequence different descriptions of the star which are equivalent to first order could lead to different results with respect to the stability of the star.

References in corpus (7)

• A new class of unstable modes of rotating relativistic stars
• Gravitational waves from hot young rapidly rotating neutron stars
• Gravitational Radiation Instability in Hot Young Neutron Stars
• Axial instability of rotating relativistic stars
• The r-mode instability in rotating neutron stars
• On the r-mode spectrum of relativistic stars in the low-frequency approximation
• On the r-mode spectrum of relativistic stars: Inclusion of the radiation reaction