Chiral symmetry breaking in QCD Lite

Abstract

A distinctive feature of the presence of spontaneous chiral symmetry breaking in QCD is the condensation of low modes of the Dirac operator near the origin. The rate of condensation must be equal to the slope of (Mpi^2 Fpi^2)/2 with respect to the quark mass m in the chiral limit, where Mpi and Fpi are the mass and the decay constant of the Nambu-Goldstone bosons. We compute the spectral density of the (Hermitian) Dirac operator, the quark mass, the pseudoscalar meson mass and decay constant by numerical simulations of lattice QCD with two light degenerate Wilson quarks. We use CLS lattices at three values of the lattice spacing in the range 0.05-0.08 fm, and for several quark masses corresponding to pseudoscalar mesons masses down to 190 MeV. Thanks to this coverage of parameters space, we can extrapolate all quantities to the chiral and continuum limits with confidence. The results show that the low quark modes do condense in the continuum as expected by the Banks-Casher mechanism, and the rate of condensation agrees with the Gell-Mann-Oakes-Renner (GMOR) relation. For the renormalisation-group-invariant ratios we obtain [Σ^RGI]^(1/3)/F =2.77(2)(4) and Lambda^MSbar/F = 3.6(2), which correspond to [Σ^\MSbar(2 GeV)]^(1/3) =263(3)(4) MeV and F=85.8(7)(20) MeV if FK is used to set the scale by supplementing the theory with a quenched strange quark.

arXiv comment4 pages, 3 figures, 1 table

References in corpus (14)

• Non-perturbative quark mass renormalization in quenched lattice QCD
• Critical slowing down and error analysis in lattice QCD simulations
• The strange quark mass and Lambda parameter of two flavor QCD
• From chiral Random Matrix Theory to chiral Perturbation Theory
• Computation of the strong coupling in QCD with two dynamical flavours
• Chiral symmetry breaking and the Banks--Casher relation in lattice QCD with Wilson quarks
• Non-perturbative quark mass renormalization in two-flavor QCD
• Stability of lattice QCD simulations and the thermodynamic limit
• Microscopic Spectrum of the Wilson Dirac Operator
• A precise determination of the psibar-psi anomalous dimension in conformal gauge theories
• QCD with light Wilson quarks on fine lattices (II): DD-HMC simulations and data analysis
• Determination of the chiral condensate from QCD Dirac spectrum on the lattice
• Chiral condensate from the twisted mass Dirac operator spectrum
• Spectral density of the Dirac operator in two-flavour QCD

Cited by in corpus (15)

• FLAG Review 2019
• Lattice QCD calculation of hadronic light-by-light scattering
• Chiral properties of (2+1)-flavor QCD in strong magnetic fields at zero temperature
• Spectral density of the Dirac operator in two-flavour QCD
• Lattice study of large $N_c$ QCD
• Chiral Symmetry Breaking on the Lattice
• Vacuum correlators at short distances from lattice QCD
• Spontaneous chiral symmetry breaking in holographic soft wall models
• Extraction of bare Form Factors for ${\mathrm{B}}_{\mathrm{s}}\to \mathrm{K}\ell \nu$ Decays in non-perturbative HQET
• The Quark Condensate in Multi-Flavour QCD - Planar Equivalence Confronting Lattice Simulations
• Holographic Dissipative Properties of Non-relativistic Black Branes with Hyperscaling Violation
• Short distance singularities and automatic O($a$) improvement: the cases of the chiral condensate and the topological susceptibility
• The pion quasiparticle in the low-temperature phase of QCD
• Chiral Properties of $(2+1)$-Flavor QCD in Magnetic Fields at Zero Temperature
• Photon emissivity of the quark-gluon plasma: a lattice QCD analysis of the transverse channel