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arXiv · 1511.08209

Gravity-dominated unequal-mass black hole collisions

Ulrich Sperhake·Emanuele Berti·Vitor Cardoso·Frans Pretorius
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Abstract

We continue our series of studies of high-energy collisions of black holes investigating unequal-mass, boosted head-on collisions in four dimensions. We show that the fraction of the center-of-mass energy radiated as gravitational waves becomes independent of mass ratio and approximately equal to $13\%$ at large energies. We support this conclusion with calculations using black hole perturbation theory and Smarr's zero-frequency limit approximation. These results lend strong support to the conjecture that the detailed structure of the colliding objects is irrelevant at high energies.

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Ulrich Sperhake, Emanuele Berti, Vitor Cardoso, Frans Pretorius. 2015-11-25. Gravity-dominated unequal-mass black hole collisions. https://doi.org/10.1103/physrevd.93.044012

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