Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hierarchical Systems in Open Clusters   In this paper we study the formation, evolution and disruption of
hierarchical systems in open clusters. With this purpose, N-body simulations of
star clusters containing an initial population of binaries have been carried
out using Aarseth's NBODY4 and NBODY5 codes. Stable triples may form from
strong interactions of two binaries in which the widest pair is disrupted. The
most frequent type of hierarchical systems found in the cluster models are
triples in which the outer star is single, but in some cases the outer body is
also a binary, giving a hierarchical quadruple. Many triple systems are
non-coplanar and the presence of even a very distant and small outer companion
may affect the orbital parameters of the inner binary, including a possible
mechanism of significant shrinkage if the binary experiences a weak tidal
dissipation. The main features of these systems are analyzed in order to derive
general properties which can be checked by observations. The formation of
exotic objects, such as blue stragglers and white dwarf binaries, inside
hierarchical triple systems is particularly interesting.

2
The categories of this paper are: math
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
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The categories of this paper are: cs
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics