Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Remnant Black Hole Kicks and Implications for Hierarchical Mergers   When binary black holes merge in dense star clusters, their remnants can pair
up with other black holes in the cluster, forming heavier and heavier black
holes in a process called hierarchical merger. The most important condition for
hierarchical merger to occur is that remnants formed by mergers are retained by
the host star cluster. Using the publicly available gravitational-wave event
database, we infer the magnitudes of kick velocities imparted to the remnant
black holes due to anisotropic emission of gravitational waves and use that to
quantify the retention probability of each event as a function of the escape
speed of the star cluster. Among the second gravitational-wave transient
catalog (GWTC-2) events, GW190814 provides the tightest constraint on the kick
magnitude with ${\rm V_{kick}}=74_{-7}^{+10}$ km/s at the 90% credible level.
We find that star clusters with escape speeds of 200 km/s can retain about 50%
of the events in the GWTC-2. Using the escape speed distributions of nuclear
star clusters and globular clusters, we find that $\sim 17$ (2) remnants of
GWTC-2 may be retained by the host star cluster if all GWTC-2 events occurred
in nuclear (globular) clusters. Our study demonstrates the importance of
folding in kick velocity inferences in future studies of hierarchical mergers.

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The categories of this paper are: bayes-an
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The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
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The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: math
4
The categories of this paper are: cond-mat