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Nonlinear evolution of r-modes in rotating relativistic stars

Jose A. Font·Nikolaos Stergioulas
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Abstract

A numerical study of nonlinear r-modes in isentropic, rapidly rotating relativistic stars, via 3-D general-relativistic hydrodynamical evolutions, is presented. On dynamical timescales, we find no evidence for strong coupling of r-modes to other modes at amplitudes of order one or larger. Therefore, unless nonlinear saturation sets in on longer timescales, the maximum r-mode amplitude is of order one. An absolute upper limit on the amplitude is set by causality. Our simulations also show that r-modes and inertial modes in isentropic stars are discrete modes, with no evidence for the existence of a continuous part in the spectrum.

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Jose A. Font, Nikolaos Stergioulas. 2000-11-03. Nonlinear evolution of r-modes in rotating relativistic stars. https://arxiv.org/abs/astro-ph/0011083

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