title: Binary-black-hole encounters, gravitational bursts, and maximum final spin.
abstract: The spin of the final black hole in the coalescence of nonspinning black holes is determined by the "residual" orbital angular momentum of the binary. This residual momentum consists of the orbital angular momentum that the binary is not able to shed in the process of merging. We study the angular momentum radiated, the spin of the final black hole, and the gravitational bursts in a sequence of equal mass encounters. The initial orbital configurations range from those producing an almost direct infall to others leading to numerous orbits before infall, with multiple bursts of radiation. Our sequence consists of orbits with fixed impact parameter. What varies is the initial linear momentum of the black holes. For this sequence, the final black hole of mass M_{h} gets a maximum spin parameter a/M_{h} approximately 0.823, with this maximum occurring for initial orbital angular momentum L/M_{h};{2} approximately 1.176.
authors.affiliation: Center for Gravitational Wave Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Washik
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