Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A comprehensive Nbody study of mass segregation in star clusters: Energy
  equipartition and escape   We address the dynamical evolution of an isolated self--gravitating system
with two stellar mass groups. We vary the individual ratio of the heavy to
light bodies, $\mu$ from 1.25 to 50 and alter also the fraction of the total
heavy mass $\MH$ from 5% to 40% of the whole cluster mass. Clean-cut properties
of the cluster dynamics are examined, like core collapse, the evolution of the
central potential, as well as escapers. We present in this work collisional
$N$-body simulations, using the high--order integrator NBODY6++ with up to
${\cal N}_{\star}=2\cdot 10^4$ particles improving the statistical significancy
of the lower--${\cal N}_{\star}$ simulations by ensemble averages.
Equipartition slows down the gravothermal contraction of the core slightly.
Beyond a critical value of $\mu \approx 2$, no equipartition can be achieved
between the different masses; the heavy component decouples and collapses. For
the first time the critical boundary between Spitzer--stable and --unstable
systems is demonstrated in direct $N$-body models.

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The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
18
The categories of this paper are: econ
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The categories of this paper are: q-alg