Kurtosis and compressibility near the chiral phase transition

2008/09/18 by B. Stokić, Bengt Friman, B. Friman +1 · 1 citation
Mathematics · Physics and Astronomy · #Compressibility #Condensed matter physics #High-Energy Particle Collisions Research #Kurtosis #Mathematics #Observable #Particle physics #Particle physics theoretical and experimental studies #Phase (matter) #Phase diagram #Phase transition #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum electrodynamics #Quantum mechanics #Quark #Thermodynamics #Tricritical point #Yukawa potential #hep-ph

paper · pdf · doi:10.1016/j.physletb.2009.02.018

published as Phys.Lett.B673:192-196,2009

arxiv created 2008/09/18 · openalex publication_date 2009/02/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

The properties of net quark number fluctuations in the vicinity of the QCD chiral phase transition are discussed in terms of an effective chiral model in the mean-field approximation. We focus on the ratio of the fourth- to second- order cumulants (kurtosis) and the compressibility of the system and discuss their dependence on the pion mass. It is shown that near the chiral phase transition, both observables are sensitive to the value of m_π. For physical m_π, the kurtosis exhibits a peak whereas the inverse compressibility shows a dip at the pseudocritical temperature. These structures disappear for large m_π. Our results, obtained in an effective model with two flavors, are qualitatively consistent with recent results of 2+1 flavor lattice gauge theory. We also discuss the high- and low-temperature properties of these observables and the role of the coupling of the quark degrees of freedom to the Polyakov loop.

Citations

• Susceptibilities and speed of sound from the Polyakov-Nambu-Jona-Lasinio model
• Chiral effective model with the Polyakov loop
• Quark number fluctuations in a chiral model at finite baryon chemical potential
• Fluctuations, strangeness, and quasiquarks in heavy-ion collisions from lattice QCD
• Critical point of QCD at finite T and , lattice results for physical quark masses
• Thermodynamics at non-zero baryon number density: a comparison of lattice and hadron resonance gas model calculations
• Thermodynamics of the PNJL model
• The QCD equation of state for two flavours at non-zero chemical potential
• Simple patterns for nonlinear susceptibilities nearTc
• Universality, the QCD critical and tricritical point, and the quark number susceptibility
• Density Fluctuations in the Presence of Spinodal Instabilities
• Chiral phase transition in the presence of spinodal decomposition
• Quark number susceptibilities and the Wróblewski parameter

Cited by

• Quark number fluctuations at finite temperature and finite chemical potential via the Dyson-Schwinger equation approach