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arXiv · gr-qc/0701164

Large Merger Recoils and Spin Flips From Generic Black-Hole Binaries

Manuela Campanelli·Carlos O. Lousto·Yosef Zlochower·David Merritt
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Abstract

We report the first results from evolutions of a generic black-hole binary, i.e. a binary containing unequal mass black holes with misaligned spins. Our configuration, which has a mass ratio of 2:1, consists of an initially non-spinning hole orbiting a larger, rapidly spinning hole (specific spin a/m = 0.885), with the spin direction oriented -45 degrees with respect to the orbital plane. We track the inspiral and merger for ~2 orbits and find that the remnant receives a substantial kick of 454 km/s, more than twice as large as the maximum kick from non-spinning binaries. The remnant spin direction is flipped by 103 degrees with respect to the initial spin direction of the larger hole. We performed a second run with anti-aligned spins, a/m = +-0.5 lying in the orbital plane that produces a kick of 1830 km/s off the orbital plane. This value scales to nearly 4000 km/s for maximally spinning holes. Such a large recoil velocity opens the possibility that a merged binary can be ejected even from the nucleus of a massive host galaxy.

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Manuela Campanelli, Carlos O. Lousto, Yosef Zlochower, David Merritt. 2007-03-02. Large Merger Recoils and Spin Flips From Generic Black-Hole Binaries. https://doi.org/10.1086/516712

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