Intermediate-Mass Black Holes in binary-rich star clusters. (arXiv:1901.05063v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Subr_L/0/1/0/all/0/1">L. Subr</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fragione_G/0/1/0/all/0/1">G. Fragione</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dabringhausen_J/0/1/0/all/0/1">J. Dabringhausen</a>
There is both theoretical expectation and some observational clues that
intermediate mass black holes reside in nuclei of globular clusters. In order
to find an independent indicator for their existence, we investigate in this
paper how an IMBH manifests itself through its dynamical interaction with a
binary rich globular cluster of moderate extension and mass. By means of direct
$N$-body integration we follow the dynamical evolution of models of such a
system over a time span of $approx$ 0.8 Gyr and compare the cases with and
without the primordial binaries as well as with and without the IMBH. In accord
with previous results, we show that when present the IMBH develops a power-law
density cusp of stars around it, regardless of the binary population in the
cluster. If, however, binaries are present, their interaction with the IMBH
leads to the production of high velocity escapers at a rate of the order of 0.1
Myr$^{-1}$. These stars may contribute to the population of high-velocity stars
observed in the Galaxy. Clusters hosting the IMBH together with high number of
binaries also form a denser halo of marginally unbound stars than clusters that
lack either the IMBH or the rich binary population. Finally, we show that the
binary population leads to an increased rate of direct interactions of stars
with the IMBH, potentially observable as tidal disruption events.
There is both theoretical expectation and some observational clues that
intermediate mass black holes reside in nuclei of globular clusters. In order
to find an independent indicator for their existence, we investigate in this
paper how an IMBH manifests itself through its dynamical interaction with a
binary rich globular cluster of moderate extension and mass. By means of direct
$N$-body integration we follow the dynamical evolution of models of such a
system over a time span of $approx$ 0.8 Gyr and compare the cases with and
without the primordial binaries as well as with and without the IMBH. In accord
with previous results, we show that when present the IMBH develops a power-law
density cusp of stars around it, regardless of the binary population in the
cluster. If, however, binaries are present, their interaction with the IMBH
leads to the production of high velocity escapers at a rate of the order of 0.1
Myr$^{-1}$. These stars may contribute to the population of high-velocity stars
observed in the Galaxy. Clusters hosting the IMBH together with high number of
binaries also form a denser halo of marginally unbound stars than clusters that
lack either the IMBH or the rich binary population. Finally, we show that the
binary population leads to an increased rate of direct interactions of stars
with the IMBH, potentially observable as tidal disruption events.
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