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Supernova kick strengths and their probability of producing specific spin-orbit misalignments in the resulting black holes.
Inferences about supernova physics from gravitational-wave measurements: GW151226 spin misalignment as an indicator of strong black-hole natal kicks
By Richard O'Shaughnessy, Davide Gerosa, Daniel Wysocki
Published in Physical Review Letters 119, 011101 (Thursday, July 6, 2017)


The inferred parameters of the binary black hole GW151226 are consistent with nonzero spin for the most massive black hole, misaligned from the binary's orbital angular momentum. If the black holes formed through isolated binary evolution from an initially aligned binary star, this misalignment would then arise from a natal kick imparted to the first-born black hole at its birth during stellar collapse. We use simple kinematic arguments to constrain the characteristic magnitude of this kick, and find that a natal kick vk≳50 km/s must be imparted to the black hole at birth to produce misalignments consistent with GW151226. Such large natal kicks exceed those adopted by default in most of the current supernova and binary evolution models.

CCRG Authors

O'Shaughnessy, Richard