Vector and Axial-Vector correlators in a instanton-like quark model

Abstract

The behavior of the vector Adler function at spacelike momenta is studied in the framework of a covariant chiral quark model with instanton-like quark-quark interaction. The model reproduces the Adler function and $V-A$ correlator extracted from the ALEPH and OPAL data on hadronic $\tau$ lepton decays, transformed into the Euclidean domain via dispersion relations. The leading order contribution from hadronic part of the photon vacuum polarization to the anomalous magnetic moment of the muon, $a_{\mu}^{\mathrm{hvp}(1)} $, is estimated.