Polyakov-loop suppression of colored states in a quark-meson-diquark plasma

TL;DR

This paper investigates how the Polyakov loop suppresses colored states like diquarks in a quark-meson-diquark plasma, affecting thermodynamics and particle abundances during chiral symmetry restoration.

Contribution

It introduces a generalized Beth-Uhlenbeck approach within the PNJL model to analyze meson and diquark dissociation and the impact of Polyakov-loop suppression on colored states.

Findings

Diquark abundance is suppressed below the chiral restoration temperature due to Polyakov-loop coupling.

Mesons, being color singlets, are unaffected by Polyakov-loop suppression.

Above the chiral restoration temperature, mesons and diquarks are both suppressed by the Mott effect, with pressure contributions balancing out.

Abstract

A quark-meson-diquark plasma is considered within the PNJL model for dynamical chiral symmetry breaking and restoration in quark matter. Based on a generalized Beth-Uhlenbeck approach to mesons and diquarks we present the thermodynamics of this system including the Mott dissociation of mesons and diquarks at finite temperature. A striking result is the suppression of the diquark abundance below the chiral restoration temperature by the coupling to the Polyakov loop, because of their color degree of freedom. This is understood in close analogy to the suppression of quark distributions by the same mechanism. Mesons as color singlets are unaffected by the Polyakov-loop suppression. At temperatures above the chiral restoration mesons and diquarks are both suppressed due to the Mott effect, whereby the positive resonance contribution to the pressure is largely compensated by the negative scattering contribution in accordance with the Levinson theorem.