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arXiv · 1606.07147

Gravitational waves from supermassive stars collapsing to a supermassive black hole

Masaru Shibata·Yuichiro Sekiguchi·Haruki Uchida·Hideyuki Umeda
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Abstract

We derive the gravitational waveform from the collapse of a rapidly rotating supermassive star (SMS) core leading directly to a seed of a supermassive black hole (SMBH) in axisymmetric numerical-relativity simulations. We find that the peak strain amplitude of gravitational waves emitted during the black-hole formation is $\approx 5 \times 10^{-21}$ at the frequency $f \approx 5$\,mHz for an event at the cosmological redshift $z=3$, if the collapsing SMS core is in the hydrogen-burning phase. Such gravitational waves will be detectable by space laser interferometric detectors like eLISA with signal-to-noise ratio $\approx 10$, if the sensitivity is as high as LISA for $f=1$--10\,mHz. The detection of the gravitational-wave signal will provide a potential opportunity for testing the direct-collapse scenario for the formation of a seed of SMBHs.

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Masaru Shibata, Yuichiro Sekiguchi, Haruki Uchida, Hideyuki Umeda. 2016-06-23. Gravitational waves from supermassive stars collapsing to a supermassive black hole. https://doi.org/10.1103/physrevd.94.021501

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