When unequal-mass black holes merge , the final black hole receives a “ kick ” due to the asymmetric loss of linear momentum in the gravitational radiation emitted during the merger .
The magnitude of this kick has important astrophysical consequences .
Recent breakthroughs in numerical relativity allow us to perform the largest parameter study undertaken to date in numerical simulations of binary black hole inspirals .
We study non-spinning black-hole binaries with mass ratios from q = M _ { 1 } / M _ { 2 } = 1 to q = 0.25 ( \eta = q / ( 1 + q ) ^ { 2 } from 0.25 to 0.16 ) .
We accurately calculate the velocity of the kick to within 6 % , and the final spin of the black holes to within 2 % .
A maximum kick of 175.2 \pm 11 km s ^ { -1 } is achieved for \eta = 0.195 \pm 0.005 .