Resonance effective theory approach to tau -> 3 pi nu_tau decays

DANIEL GOMEZ DUMM; ANTONIO PICH; JORGE PORTOLES

Angra dos Reis

Workshop; IX Hadron Physics - VII Relativistic Aspects of Nuclear Physics 2004; 2004

The decays tau -> 3 pi nu_tau are analyzed in the framework of the resonance effective theory of QCD. We derive the effective chiral Lagrangian relevant for the evaluation of the hadronic axial-vector current, taking into account the constraints imposed by QCD on the high energy asymptotic behaviour. Then we fit the unknown parameters to the spectral function and branching ratio measured by ALEPH, showing that the theory is in good agreement with experimental data