Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Phase Diagram of the Quark-Meson Model   Within the proper-time renormalization group approach, the chiral phase
diagram of a two-flavor quark-meson model is studied. In the chiral limit, the
location of the tricritical point which is linked to a Gaussian fixed point, is
determined. For quark chemical potentials smaller than the tricritical one the
second-order phase transition belongs to the O(4) universality class. For
temperatures below the tricritical one we find initially a weak first-order
phase transition which is commonly seen in model studies and also in recent
lattice simulations. In addition, below temperatures of T <~ 17 MeV we find two
phase transitions. The chiral restoration transition is initially also of
first-order but turns into a second-order transition again. This leads to the
possibility that there may be a "second tricritical" point in the QCD phase
diagram in the chiral limit.

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The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys