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Non-linear radial oscillations of neutron stars: Mode-coupling results

Uli Sperhake·Philippos Papadopoulos·Nils Andersson
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Abstract

The non-linear behaviour of oscillation modes in compact stars is a topic of considerable current interest. Accurate numerical studies of such phenomena are likely to require powerful new approaches to both fluid and spacetime computations. We propose that a key ingredient of such methods will be the non-linear evolution of deviations from the background stationary equilibrium star. We investigate the feasibility of this approach by applying it to non-linear radial oscillations of a neutron star, and explore numerically various non-linear features of this problem, for a large range of amplitudes. Quadratic and higher order mode coupling and non-linear transfer of energy is demonstrated and analysed in detail.

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Uli Sperhake, Philippos Papadopoulos, Nils Andersson. 2001-10-22. Non-linear radial oscillations of neutron stars: Mode-coupling results. https://arxiv.org/abs/astro-ph/0110487

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