Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Do Cluster Cooling Flows Survive Head-on Galaxy Cluster Mergers?   We report the results of recent numerical simulations of the head-on merger
of a cooling flow cluster with an infalling subcluster of galaxies. These
simulations examined the effects of different types of cluster mergers (with
16:1 and 4:1 mass ratios) on the evolution of cluster cooling flows (mass
accretion rates of 100 and 400 M/year. The 2-dimensional simulations were
performed with a Hydro/N-body code on a uniform grid with a resolution of 20
kpc.
  We find that the ram-pressure of the infalling gas is crucial in determining
the fate of the cooling flow as disruption occurs when a substantial amount of
subcluster gas reaches the primary's core. In such cases, the subcluster gas
can increase the central cooling time by displacing the high-density cooling
gas and by heating it via shocks and turbulent gas motions. Moreover, the fate
of a merging cooling flow is also dependent on its initial cooling time. In
cases where the initial cooling time is very small then, even if the flow is
disrupted, the central cooling time will remain less than a Hubble time and the
flow will likely re-establish itself. This has an important observational
consequence because such clusters will be classified as cooling flows even
though they have experienced a significant merger. In addition, there is a time
delay (1-2 Gyrs) between core-crossing and the point at which the central
cooling time of a disrupted flow becomes of order a Hubble time (abridged).

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The categories of this paper are: math
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
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The categories of this paper are: eess
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
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The categories of this paper are: cs
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph