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Gravitational radiation from a torus around a black hole

Maurice H. P. M. van Putten
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Abstract

Long gamma-ray bursts (GRBs) from rapidly spinning black hole-torus systems may represent hypernovae or black hole-neutron star coalescence. We show that the torus may radiate gravitational radiation powered by the spin-energy of the black hole in the presence of non-axisymmetries. The coupling to the spin-energy of the black hole is due to equivalence in poloidal topology to pulsar magnetospheres. Results calculated in the suspended accretion state indicate that GRBs are potentially the most powerful LIGO/VIRGO burst-sources in the Universe, with an expected duration of 10-15s on a horizontal branch of 1-2kHz in the $\dot{f}(f)-$diagram.

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Maurice H. P. M. van Putten. 2001-07-01. Gravitational radiation from a torus around a black hole. https://doi.org/10.1103/physrevlett.87.091101

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