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arXiv · 0801.2090

Dynamical excitation of space-time modes of compact objects

Sebastiano Bernuzzi·Alessandro Nagar·Roberto De Pietri
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Abstract

We discuss, in the perturbative regime, the scattering of Gaussian pulses of odd-parity gravitational radiation off a non-rotating relativistic star and a Schwarzschild Black Hole. We focus on the excitation of the $w$-modes of the star as a function of the width $b$ of the pulse and we contrast it with the outcome of a Schwarzschild Black Hole of the same mass. For sufficiently narrow values of $b$, the waveforms are dominated by characteristic space-time modes. On the other hand, for sufficiently large values of $b$ the backscattered signal is dominated by the tail of the Regge-Wheeler potential, the quasi-normal modes are not excited and the nature of the central object cannot be established. We view this work as a useful contribution to the comparison between perturbative results and forthcoming $w$-mode 3D-nonlinear numerical simulation.

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Sebastiano Bernuzzi, Alessandro Nagar, Roberto De Pietri. 2008-03-06. Dynamical excitation of space-time modes of compact objects. https://doi.org/10.1103/physrevd.77.044042

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