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arXiv · hep-ph/0102260

Vector and axial-vector correlators in a chirally symmetric model

M. Urban·M. Buballa·J. Wambach
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Abstract

We present a chirally symmetric hadronic model for the vector and axial-vector correlators in vacuum. The dominant contributions to these correlators come from intermediate pions, rho and a_1 mesons which are calculated in one-loop approximation. The resulting spectral functions are compared with the data obtained by the ALEPH collaboration from tau decay. In the vector channel we find good agreement up to q^2 = 1 GeV^2, in the transverse axial-vector channel up to q^2 = 2 GeV^2, corresponding to the regimes dominated by two-pion or three-pion decay channels, respectively. The longitudinal axial correlator is in almost perfect agreement with the PCAC result.

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M. Urban, M. Buballa, J. Wambach. 2001-07-18. Vector and axial-vector correlators in a chirally symmetric model. https://doi.org/10.1016/s0375-9474(01)01248-9

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