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arXiv · gr-qc/0008019

The rotational modes of relativistic stars: Analytic results

Keith H. Lockitch·Nils Andersson·John L. Friedman
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Abstract

We study the r-modes and rotational ``hybrid'' modes of relativistic stars. As in Newtonian gravity, the spectrum of low-frequency rotational modes is highly sensitive to the stellar equation of state. If the star and its perturbations obey the same one-parameter equation of state (as with isentropic stars), there exist {\it no pure r-modes at all} - no modes whose limit, for a star with zero angular velocity, is an axial-parity perturbation. Rotating stars of this kind similarly have no pure g-modes, no modes whose spherical limit is a perturbation with polar parity and vanishing perturbed pressure and density. We compute the post-Newtonian corrections to the $l=m$ r-modes of isentropic and non-isentropic uniform density stars.

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Keith H. Lockitch, Nils Andersson, John L. Friedman. 2000-08-08. The rotational modes of relativistic stars: Analytic results. https://doi.org/10.1103/physrevd.63.024019

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