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Grazing Collisions of Black Holes via the Excision of Singularities

Steve Brandt·Randall Correll·Roberto Gomez·Mijan Huq·Pablo Laguna·Luis Lehner·Pedro Marronetti·Richard A. Matzner·David Neilsen·Jorge Pullin·Erik Schnetter·Deirdre Shoemaker·Jeffrey Winicour
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Abstract

We present the first simulations of non-headon (grazing) collisions of binary black holes in which the black hole singularities have been excised from the computational domain. Initially two equal mass black holes $m$ are separated a distance $\approx10m$ and with impact parameter $\approx2m$. Initial data are based on superposed, boosted (velocity $\approx0.5c$) solutions of single black holes in Kerr-Schild coordinates. Both rotating and non-rotating black holes are considered. The excised regions containing the singularities are specified by following the dynamics of apparent horizons. Evolutions of up to $t \approx 35m$ are obtained in which two initially separate apparent horizons are present for $t\approx3.8m$. At that time a single enveloping apparent horizon forms, indicating that the holes have merged. Apparent horizon area estimates suggest gravitational radiation of about 2.6% of the total mass. The evolutions end after a moderate amount of time because of instabilities.

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Steve Brandt, Randall Correll, Roberto Gomez, Mijan Huq, Pablo Laguna, Luis Lehner, Pedro Marronetti, Richard A. Matzner, David Neilsen, Jorge Pullin, Erik Schnetter, Deirdre Shoemaker, Jeffrey Winicour. 2000-09-14. Grazing Collisions of Black Holes via the Excision of Singularities. https://doi.org/10.1103/physrevlett.85.5496

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