Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phenomenological improvement of the linear-$\sigma$ model in the
  large-N_c limit   The linear-$\sigma$ model has been widely used to describe the chiral phase
transition. Numerically, the critical temperature $T_{c}$ of the chiral phase
transition is in agreement with other effective theories of QCD. However, in
the large-$N_{c}$ limit $T_{c}$ scales as $\sqrt{N_{c}}$ which is not in line
with the NJL model and with basic expectations of QCD, according to which
$T_{c}$ is --just as the deconfinement phase transition- $N_{c}$-independent.
This mismatch can be corrected by a phenomenologically motivated temperature
dependent parameter.

35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom