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arXiv · 1909.04678

Intermediate mass black holes' effect on compact object binaries

Barnabás Deme·Yohai Meiron·Bence Kocsis
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Abstract

Although their existence is not yet confirmed observationally, intermediate mass black holes (IMBHs) may play a key role in the dynamics of galactic nuclei. In this paper, we neglect the effect of the nuclear star cluster itself and investigate only how a small reservoir of IMBHs influences the secular dynamics of stellar-mass black hole binaries, using N-body simulations. We show that our simplifications are valid and that the IMBHs significantly enhance binary evaporation by pushing the binaries into the Hill-unstable region of parameter space, where they are separated by the SMBH's tidal field. For binaries in the S-cluster region of the Milky Way, IMBHs drive the binaries to merge in up to 1-6% of cases, assuming five IMBHs within 5 pc of mass 10,000 solar masses each. Observations of binaries in the Galactic center may strongly constrain the population of IMBHs therein.

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Barnabás Deme, Yohai Meiron, Bence Kocsis. 2020-02-28. Intermediate mass black holes' effect on compact object binaries. https://doi.org/10.3847/1538-4357%2Fab7921

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