Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Energy densities and equilibration in heavy ion collisions at sqrt(s) =
  200 GeV with the quark-gluon string model   We study thermodynamic characteristica of ultra-relativistic Au+Au collisions
at RHIC energy sqrt(s) = 200 GeV within the framework of a microscopic
transport model, namely the quark-gluon string model (QGSM). The temporal
evolution of the local energy density, transverse and longitudinal pressure and
equilibration times are considered. In contrast to complete equilibration which
is even in central reactions hardly achieved, pre-equilibrium stages with
energy densities well above the critical energy density predicted by lattice
QCD are established at short time scales. Corresponding energy density profiles
at proper time tau = 1 fm/c compare well with hydrodynamical assumptions for
initial energy density distributions.

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The categories of this paper are: chem-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con