Equation of state and heavy-quark free energy at finite temperature and density in two flavor lattice QCD with Wilson quark action

2009/09/30 by S. Ejiri, Shinji Ejiri, Y. Maezawa +8 · 85 citations
Physics and Astronomy · #Gluon #Hadron #High-Energy Particle Collisions Research #Lattice QCD #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quark #Quark–gluon plasma #hep-lat #hep-ph #nucl-th

paper · pdf · doi:10.1103/physrevd.82.014508

published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 82(1), 014508 (American Physical Society) · 38 pages, 63 figures

arxiv created 2010/07/01 · openalex publication_date 2010/07/29 · arxiv updated 2014/11/20 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We study the equation of state at finite temperature and density in two-flavor QCD with the renormalization group improved gluon action and the clover-improved Wilson quark action on a 16³\ifmmode×\else\texttimes\fi4 lattice. Along the lines of constant physics at m_PS/m_V=0.65 and 0.80, we compute the second and forth derivatives of the grand canonical partition function with respect to the quark chemical potential \ensuremathμ_q=(\ensuremathμ_u+\ensuremathμ_d)/2 and the isospin chemical potential \ensuremathμ_I=(\ensuremathμ_u\ensuremath-\ensuremathμ_d)/2 at vanishing chemical potentials, and study the behaviors of thermodynamic quantities at finite \ensuremathμ_q using these derivatives for the case \ensuremathμ_I=0. In particular, we study density fluctuations at nonezero temperature and density by calculating the quark number and isospin susceptibilities and their derivatives with respect to \ensuremathμ_q. To suppress statistical fluctuations, we also examine new techniques applicable at low densities. We find a large enhancement in the fluctuation of the quark number when the density increased near the pseudocritical temperature, suggesting a critical point at finite \ensuremathμ_q terminating the first order transition line between hadronic and quark-gluon-plasma phases. This result agrees with the previous results using staggered-type quark actions qualitatively. Furthermore, we study heavy-quark free energies and Debye screening masses at finite density by measuring the first and second derivatives of these quantities for various color channels of heavy quark-quark and quark-antiquark pairs. The results suggest that, to the leading order of \ensuremathμ_q, the interaction between two quarks becomes stronger at finite densities, while that between quark and antiquark becomes weaker.

Citations

• Remarks on the multiparameter reweighting method for the study of lattice QCD at nonzero temperature and density
• Toward a theory of binary bound states in the quark-gluon plasma
• Determination of QCD phase diagram from the imaginary chemical potential region
• 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
• On the critical end point of QCD
• Pressure and nonlinear susceptibilities in QCD at finite chemical potentials
• Isentropic equation of state of 2-flavor QCD
• Transition temperature in QCD
• Long-Distance Behavior of qFormula Color Dependent Potentials at Finite Temperature
• QCD thermal phase transition in the presence of a small chemical potential

Cited by

• Casimir free energy for massive fermions: a comparative study of various approaches
• Properties of 2+1-flavor QCD in the imaginary chemical potential region: A model approach
• Heavy quarkonium in extreme conditions