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arXiv · 1704.07175

Black hole ringdown echoes and howls

Hiroyuki Nakano·Norichika Sago·Hideyuki Tagoshi·Takahiro Tanaka
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Abstract

Recently the possibility of detecting echoes of ringdown gravitational waves from binary black hole mergers was shown. The presence of echoes is expected if the black hole is surrounded by a mirror that reflects gravitational waves near the horizon. Here, we present slightly more sophisticated templates motivated by a waveform which is obtained by solving the linear perturbation equation around a Kerr black hole with a complete reflecting boundary condition in the stationary traveling wave approximation. We estimate that the proposed template can bring about $10\%$ improvement in the signal-to-noise ratio.

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Hiroyuki Nakano, Norichika Sago, Hideyuki Tagoshi, Takahiro Tanaka. 2017-04-24. Black hole ringdown echoes and howls. https://doi.org/10.1093/ptep/ptx093

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