Thermodynamics of the Quark-Gluon Plasma within a T-matrix approach

TL;DR

This paper investigates the thermodynamics of the quark-gluon plasma using a T-matrix approach, revealing the existence of bound states above the deconfinement temperature and comparing results with lattice QCD data.

Contribution

It introduces a non-perturbative T-matrix framework to study QGP thermodynamics and bound state dissociation, providing new insights into the strongly-coupled phase.

Findings

Bound states can survive above T_c, especially with heavier quasiparticles.

Computed QGP equations of state align with lattice QCD data.

Dissociation temperatures depend on quasiparticle masses.

Abstract

The strongly-coupled phase of the quark-gluon plasma (QGP) is studied here by resorting to a $T$-matrix formulation in which the medium is seen as a non-ideal gas of quasiparticles (quarks, antiquarks and gluons) interacting nonpertubatively. In the temperature range under study, (1-5) $T_c$, where $T_c$ is the temperature of deconfinement, the interactions are expected to be strong enough to generate bound states. The dissociation temperature of such binary bound states is thus computed here. The more the quasiparticles involved in the binary system are heavy, the more the bound state is likely to survive significantly above $T_c$. Then, the QGP equations of state at zero and small baryonic potential are computed for $N_f = 2$ and $N_f = 2 + 1$ by resorting to the Dashen, Ma and Bernstein formulation of statistical mechanics. Comparisons with current lattice QCD data are presented.