
Gergely, László Á.; Biermann, Peter L.; Caramete, Laurentiu I. . Supermassive black hole spinflip during the inspiral. Classical and Quantum Gravity, Volume 27, p. Issue 19, , 2010.
Abstract:
During postNewtonian evolution of a compact binary, a mass ratio ν different from 1 provides a second small parameter, which can lead to unexpected results. We present a statistics of supermassive black hole candidates, which enables us first to derive their mass distribution, and then to establish a logarithmically even probability in ν of the mass ratios at their encounter. In the mass ratio range ν in (1/30, 1/3) of supermassive black hole mergers representing 40% of all possible cases, the combined effect of spinorbit precession and gravitational radiation leads to a spinflip of the dominant spin during the inspiral phase of the merger. This provides a mechanism for explaining a large set of observations on Xshaped radio galaxies. In another 40% with mass ratios ν in (1/30, 1/1000) a spinflip never occurs, while in the remaining 20% of mergers with mass ratios ν in (1/3, 1) it may occur during the plunge. We analyze the magnitude of the spinflip angle occurring during the inspiral as a function of the mass ratio and original relative orientation of the spin and orbital angular momentum. We also derive a formula for the final spin at the end of the inspiral in this mass ratio range.
Keywords:
General Relativity and Quantum Cosmology
URL:
http://adsabs.harvard.edu/abs/2010CQGra..27s4009G
Posted by
Laurentiu Ioan Caramete
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