Abstract

We performed a series of 1341 full numerical simulations of high 
energy collision of black holes to search for the maximum recoil
velocity after their merger.  We consider equal mass binaries with
opposite spins pointing along their orbital plane and perform a search
of spin orientations, impact parameters, and initial linear momenta to
find the maximum recoil for a given spin magnitude $s$. This spin
sequence for $s=0.4, 0.7, 0.8, 0.85, 0.9$ is then extrapolated to the
extreme case, $s=1$, to obtain an estimated maximum recoil velocity of
$26,677pm 470$ km/s, thus nearly $9\%$ the speed of light.