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arXiv · 1604.00946

The evolution of a supermassive retrograde binary embedded in an accretion disk

P. B. Ivanov·J. C. B. Papaloizou·S. -J. Paardekooper·A. G. Polnarev
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Abstract

In this note we discuss the main results of a study of a massive binary with unequal mass ratio, q, embedded in an accretion disk, with its orbital rotation being opposed to that of the disk. When the mass ratio is sufficiently large, a gap opens in the disk, but the mechanism of gap formation is very different from the prograde case. Inward migration occurs on a timescale of t_ev ~ M_p/(dot M), where M_p is the mass of the less massive component (the perturber), and dot M is the accretion rate. When q<< 1, the accretion takes place mostly onto the more massive component, with the accretion rate onto the perturber being smaller than, or of order of, q^(1/3)M. However, this rate increases when supermassive binary black holes are considered and gravitational wave emission is important. We estimate a typical duration of time for which the accretion onto the perturber and gravitational waves could be detected.

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P. B. Ivanov, J. C. B. Papaloizou, S. -J. Paardekooper, A. G. Polnarev. 2016-04-04. The evolution of a supermassive retrograde binary embedded in an accretion disk. https://doi.org/10.1515/astro-2017-0216

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