The QCD scalar susceptibility and thermal scalar resonances in chiral symmetry restoration

Abstract

Building upon recent results on the role of thermal resonances in chiral symmetry restoration, we show that a description of the QCD scalar susceptibility at finite temperature $T$ saturated by the thermal properties of the lightest scalar resonance, the $f_0(500)$, is compatible both with lattice QCD data at nonzero $T$ and with the $T=0$ light resonance properties coming from experimental data. The thermal $f_0(500)$ is generated within the framework of Unitarized Chiral Perturbation Theory. This method allows us to achieve a good description of lattice QCD results with a reliable pion mass dependence. In particular, we perform direct fits to the chiral susceptibility measured in lattice data at different pion masses and temperatures, obtaining a remarkable agreement for the susceptibility and for mass differences of the light quark condensate. In addition, the fitted low-energy constants are compatible with $T=0$ phenomenology. Our results confirm the role of unitarized approaches and thermal resonances in the dynamics of the QCD transition.

References in corpus (23)

• The chiral and deconfinement aspects of the QCD transition
• The QCD transition temperature: results with physical masses in the continuum limit II.
• QCD Equation of State and Hadron Resonance Gas
• Hadron Resonance Mass Spectrum and Lattice QCD Thermodynamics
• Chiral phase transition temperature in (2+1)-Flavor QCD
• Quark mass dependence of the rho and sigma from dispersion relations and Chiral Perturbation Theory
• Relevance of the axial anomaly at the finite-temperature chiral transition in QCD
• The QCD chiral transition, $\ua$ symmetry and the Dirac spectrum using domain wall fermions
• Dispersion Relation Bounds for pi pi Scattering
• Scalar susceptibility in QCD and the multiflavor Schwinger model
• Thermal rho and sigma mesons from chiral symmetry and unitarity
• Quark-Antiquark Condensates in the Hadronic Phase
• Scalar susceptibilities and four-quark condensates in the meson gas within Chiral Perturbation Theory
• Chiral condensate in hadronic matter
• Light- and strange-quark mass dependence of the $\rho (770)$ meson revisited
• Some Remarks on the Pade Unitarization of Low-Energy Amplitudes
• Curvature of the chiral phase transition line from the magnetic equation of state of (2+1)-flavor QCD
• The role of the thermal $f_0(500)$ in chiral symmetry restoration
• Chiral perturbation theory for nonzero chiral imbalance
• Pion propagation in the linear sigma model at finite temperature
• Light quarks at finite temperature: chiral restoration and the fate of the $U(1{)}_A$ symmetry
• The pion-kaon scattering amplitude and the $K^0(700)$ and $K^{\ast }(892)$ resonances at finite temperature
• Revisiting $O(N)$ $\sigma$ model at unphysical pion masses and high temperatures