Vector and axial - vector correlators in a chirally symmetric model

نویسندگان

  • M. Urban
  • M. Buballa
  • J. Wambach
چکیده

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, ρ 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 τ 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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تاریخ انتشار 2001