2003/05/31 by A. E. Dorokhov, Wojciech Broniówski, W. Broniowski · 1 citation
Physics and Astronomy · #Chiral perturbation theory #Hadron #High-Energy Particle Collisions Research #Instanton #Isovector #Lattice QCD #Mathematical physics #Meson #Nucleon #Operator product expansion #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Pseudovector #QCD vacuum #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quark #hep-ph
paper · pdf · doi:10.1140/epjc/s2003-01386-x
published as Eur.Phys.J. C32 (2003) 79-96 · 24 pages, 14 figures, LaTex (revised version)
arxiv created 2003/09/30 · openalex publication_date 2003/12/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The behavior of nonperturbative parts of the isovector-vector and isovector and isosinglet axial-vector correlators at Euclidean momenta is studied in the framework of a covariant chiral quark model with nonlocal quark-quark interactions. The gauge covariance is ensured with the help of the P-exponents, with the corresponding modification of the quark-current interaction vertices taken into account. The low- and high-momentum behavior of the correlators is compared with the chiral perturbation theory and with the QCD operator product expansion, respectively. The V-A combination of the correlators obtained in the model reproduces quantitatively the ALEPH data on hadronic τdecays, transformed into the Euclidean domain via dispersion relations. The predictions for the electromagnetic π^± - π0 mass difference and for the pion electric polarizability are also in agreement with the experimental values. The topological susceptibility of the vacuum is evaluated as a function of the momentum, and its first moment is predicted to be χ'(0)≈ (50 MeV)2. In addition, the fulfillment of the Crewther theorem is demonstrated.