Superstatistics and the effective QCD phase diagram

R Zamora,L A Hernández,M Loewe,Martin Hentschinski,Alejandro Ayala

doi:10.1103/physrevd.98.114002

Abstract

We study the effect of a partially thermalized scenario for chiral symmetry restoration at finite temperature and quark chemical potential, and in particular for the position of the critical end point in an effective description of the QCD phase diagram. We show that these effects produce the critical end point to be displaced towards larger values of temperature and lower values of the quark chemical potential as compared to the case when the system can be regarded as completely thermalized. We conclude that these effects may be important for relativistic heavy ion collisions where the number of subsystems making the whole interaction volume can be linked to the finite number of participants in the reaction.

Highlights

The usual thermal description of a relativistic heavy-ion collision relies on the assumption that the produced matter reaches equilibrium after some time from the beginning of the reaction
We study the effect of a partially thermalized scenario for chiral symmetry restoration at finite temperature and quark chemical potential, and in particular for the position of the critical end point in an effective description of the QCD phase diagram
In this work we explore the implications of superstatistics for the location of the critical end point (CEP) in the QCD phase diagram

Summary

INTRODUCTION

The usual thermal description of a relativistic heavy-ion collision relies on the assumption that the produced matter reaches equilibrium after some time from the beginning of the reaction This equilibrium is characterized by values of temperature T and baryon chemical potential μ which are taken as common within the whole interaction volume. It seems natural to assume that this starts off in each of the interacting nucleon pair subsystems, and later spreads to the entire volume In this scenario, the temperature and chemical potential within each subsystem may not be the same for other subsystems and a superposition of statistics, one in the usual Gibbs-Boltzmann sense for particles in each subsystem, and another one, for the probability to find particular values for T and μ for a different subsystem, seems appropriate.

SUPERSTATISTICS

N β20: ð6Þ

SUPERSTATISTICS IN THE φ4 THEORY

SUPERSTATISTICS AND THE LINEAR SIGMA MODEL WITH QUARKS

SUMMARY AND OUTLOOK