title: Superkicks in hyperbolic encounters of binary black holes.
abstract: Generic inspirals and mergers of binary black holes produce beamed emission of gravitational radiation that can lead to a gravitational recoil or kick of the final black hole. The kick velocity depends on the mass ratio and spins of the binary as well as on the dynamics of the binary configuration. Studies have focused so far on the most astrophysically relevant configuration of quasicircular inspirals, for which kicks as large as approximately 3300 km s;(-1) have been found. We present the first study of gravitational recoil in hyperbolic encounters. Contrary to quasicircular configurations, in which the beamed radiation tends to average during the inspiral, radiation from hyperbolic encounters is plunge dominated, resulting in an enhancement of preferential beaming. As a consequence, it is possible in highly relativistic scatterings to achieve kick velocities as large as 10 000 km s;(-1).
authors.affiliation: Center for Gravitational Wave Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: James
authors.initials: J
authors.lastname: Healy
authors.forename: Frank
authors.initials: F
authors.lastname: Herrmann
authors.forename: Ian
authors.initials: I
authors.lastname: Hinder
authors.forename: Deirdre M
authors.initials: DM
authors.lastname: Shoemaker
authors.forename: Pablo
authors.initials: P
authors.lastname: Laguna
authors.forename: Richard A
authors.initials: RA
authors.lastname: Matzner