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arXiv · 0808.4002

Gravitational-Wave Extraction from Neutron Star Oscillations: comparing linear and nonlinear techniques

Luca Baiotti·Sebastiano Bernuzzi·Giovanni Corvino·Roberto De Pietri·Alessandro Nagar
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Abstract

The main aim of this study is the comparison of gravitational waveforms obtained from numerical simulations which employ different numerical evolution approaches and different wave-extraction techniques. For this purpose, we evolve an oscillating, non-rotating polytropic neutron-star model with two different approaches: a full nonlinear relativistic simulation (in three dimensions) and a linear simulation based on perturbation theory. The extraction of the gravitational-wave signal is performed with three methods: The gauge-invariant curvature-perturbation theory based on the Newman-Penrose scalar $ψ_4$; The gauge-invariant Regge-Wheeler-Zerilli-Moncrief metric-perturbation theory of a Schwarzschild space-time; Some generalization of the quadrupole emission formula.

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Luca Baiotti, Sebastiano Bernuzzi, Giovanni Corvino, Roberto De Pietri, Alessandro Nagar. 2009-03-11. Gravitational-Wave Extraction from Neutron Star Oscillations: comparing linear and nonlinear techniques. https://doi.org/10.1103/physrevd.79.024002

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