Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effective degrees of freedom and gluon condensation in the high
  temperature deconfined phase   The Equation of State and the properties of matter in the high temperature
deconfined phase are analyzed by a quasiparticle approach for $T> 1.2~T_c$. In
order to fix the parameters of our model we employ the lattice QCD data of
energy density and pressure. First we consider the pure SU(3) gluon plasma and
it turns out that such a system can be described in terms of a gluon condensate
and of gluonic quasiparticles whose effective number of degrees of freedom and
mass decrease with increasing temperature. Then we analyze QCD with finite
quark masses. In this case the numerical lattice data for energy density and
pressure can be fitted assuming that the system consists of a mixture of gluon
quasiparticles, fermion quasiparticles, boson correlated pairs (corresponding
to in-medium mesonic states) and gluon condensate. We find that the effective
number of boson degrees of freedom and the in-medium fermion masses decrease
with increasing temperature. At $T \simeq 1.5 ~T_c$ only the correlated pairs
corresponding to the mesonic nonet survive and they completely disappear at $T
\simeq 2 ~T_c$. The temperature dependence of the velocity of sound of the
various quasiparticles, the effects of the breaking of conformal invariance and
the thermodynamic consistency are discussed in detail.

31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int