Sensitivity of the Polyakov loop and related observables to chiral symmetry restoration

Abstract

While the Polyakov loop is an order parameter of the deconfinement transition in the heavy quark mass regime of QCD, its sensitivity to the deconfinement of light, dynamical quarks in QCD is not apparent. On the other hand, the quark mass dependence of the Polyakov loop is sensitive to the appearance of a chiral phase transition. Using lattice QCD calculations in the staggered fermion discretization scheme at finite values of the lattice spacing, $aT=1/8$, we show here, for the first time, that the Polyakov loop expectation value, and the heavy quark free energy extracted from it, behave like energy-like observables in the vicinity of the chiral phase transition temperature $T_c$. Consistent with scaling behavior of energy-like observables in the 3-$d$, O(2) universality class, the quark mass derivatives diverge in the chiral limit at $T_c$ while the temperature derivatives stay finite. The latter will develop a characteristic spike at $T_c$. This, however, may be resolved only in calculations with quark masses being two orders of magnitude smaller than those currently accessible in lattice QCD calculations.

6 pages, 3 figures

References in corpus (5)

• The equation of state in (2+1)-flavor QCD
• The QCD transition temperature: results with physical masses in the continuum limit II.
• Highly Improved Staggered Quarks on the Lattice, with Applications to Charm Physics
• The QCD Equation of State to $\mathcal{O}({\mu }_B^6)$ from Lattice QCD
• The Polyakov loop and the hadron resonance gas model

Cited by in corpus (17)

• Equation of state and speed of sound of (2+1)-flavor QCD in strangeness-neutral matter at non-vanishing net baryon-number density
• HotQCD on Multi-GPU Systems
• Lattice Constraints on the QCD Chiral Phase Transition at Finite Temperature and Baryon Density
• SIMULATeQCD: A simple multi-GPU lattice code for QCD calculations
• Towards the chiral phase transition in the Roberge-Weiss plane
• Curvature of the chiral phase transition line from the magnetic equation of state of (2+1)-flavor QCD
• Finite temperature properties of QCD with two flavors and three, four and five colors
• Microscopic Encoding of Macroscopic Universality: Scaling Properties of Dirac Eigenspectra near QCD Chiral Phase Transition
• Overview of the QCD phase diagram -- Recent progress from the lattice
• Consistent approach to study gluon quasi-particles
• Chiral and deconfinement thermal transitions at finite quark spin polarization in lattice QCD simulations
• Correlating confinement to topological fluctuations near the crossover transition in QCD
• Critical behavior towards the chiral limit at vanishing and non-vanishing chemical potentials
• Imprint of chiral symmetry restoration on the Polyakov loop and the heavy quark free energy
• Lattice QCD at Imaginary Chemical Potential in the Chiral Limit
• Chiral Symmetry Breaking and Confinement from an Interacting Ensemble of Instanton-dyons in Two-flavor Massless QCD
• Microscopic Encoding of Macroscopic Universality in QCD Chiral Phase Transition