Superkicks in ultrarelativistic encounters of spinning black holes
Author(s)
Sperhake, Ulrich; Berti, Emanuele; Cardoso, Vitor; Pretorius, Frans; Yunes, Nicolas
DownloadSperhake-2011-Superkicks in ultrar.pdf (393.3Kb)
PUBLISHER_POLICY
Publisher Policy
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Terms of use
Metadata
Show full item recordAbstract
We study ultrarelativistic encounters of two spinning, equal-mass black holes through simulations in full numerical relativity. Two initial data sequences are studied in detail: one that leads to scattering and one that leads to a grazing collision and merger. In all cases, the initial black hole spins lie in the orbital plane, a configuration that leads to the so-called superkicks. In astrophysical, quasicircular inspirals, such kicks can be as large as ∼3000 km/s; here, we find configurations that exceed ∼15 000 km/s. We find that the maximum recoil is to a good approximation proportional to the total amount of energy radiated in gravitational waves, but largely independent of whether a merger occurs or not. This shows that the mechanism predominantly responsible for the superkick is not related to merger dynamics. Rather, a consistent explanation is that the “bobbing” motion of the orbit causes an asymmetric beaming of the radiation produced by the in-plane orbital motion of the binary, and the net asymmetry is balanced by a recoil. We use our results to formulate some conjectures on the ultimate kick achievable in any black hole encounter.
Date issued
2011-01Department
Massachusetts Institute of Technology. Department of Physics; MIT Kavli Institute for Astrophysics and Space ResearchJournal
Physical Review D
Publisher
American Physical Society
Citation
Sperhake, Ulrich et al. "Superkicks in ultrarelativistic encounters of spinning black holes." Phys. Rev. D 83, 024037. (2011) © 2011 American Physical Society.
Version: Final published version
ISSN
1550-7998