Examining the crossover from hadronic to partonic phase in QCD

TL;DR

This paper proposes a QCD-consistent mechanism for the hadronic to partonic phase crossover, involving the emergence of a perturbative vacuum within the physical vacuum, modeled through a dynamical percolation approach.

Contribution

It introduces a novel mechanism for the phase transition in QCD, utilizing a percolation model to describe the vacuum crossover during increasing temperature.

Findings

Successful description of the hadronic to sQGP transition.

Model captures the crossover dynamics with temperature-dependent parameters.

Provides a QCD-consistent framework for phase transition mechanisms.

Abstract

It is argued that, due to the existence of two vacua -- perturbative and physical -- in QCD, the mechanism for the crossover from hadronic to partonic phase is hard to construct. The challenge is: how to realize the transition between the two vacua during the gradual crossover of the two phases. A possible solution of this problem is proposed and a mechanism for crossover, consistent with the principle of QCD, is constructed. The essence of this mechanism is the appearance and growing up of a kind of grape-shape perturbative vacuum inside the physical one. A dynamical percolation model based on a simple dynamics for the delocalization of partons is constructed to exhibit this mechanism. The crossover from hadronic matter to sQGP as well as the transition from sQGP to wQGP in the increasing of temperature is successfully described by using this model with a temperature dependent parameter.