Singlet V AṼ correlator within the instanton vacuum model
نویسنده
چکیده
The correlator of singlet axial-vector and vector currents in the external electromagnetic field is studied within the instanton liquid model of QCD vacuum. In the chiral limit we calculate the longitudinal w (0) L and transversal w (0) T with respect to axial-vector index invariant amplitudes at arbitrary momentum transfer q. It is demonstrated how the anomalous longitudinal part of the correlator is renormalized at low momenta due to the presence of the UA (1) anomaly.
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