Hadronization in three meson channels at tau decays and e+e- cross-section

Abstract

The hadronic form factors in semileptonic decays of the tau and low-energy e+ e- scattering into hadrons can be described accounting for the following fundamental features: the right chiral structure at low energies, the large-N_C limit of QCD and the known asymptotic behaviour of the theory. All these characteristics are implemented within our approach to the accuracy and within the limits discussed below. Our results -improved with respect to those shown in the talk (they correspond to the ones presented in the V Working Group on Generators for Low-Energy Physics held in Frascati the 6th and 7th of April, 2009) are compared to data for tau to 3pi nu_tau. Our setup in the vector current has been checked (using CVC) with e+e- to KKpi data. We predict the hadronic spectra in all tau to KKpi nu_tau charge modes. Our hadronic matrix elements are being included in the TAUOLA library and may be useful for the experimental collaborations that are analysing tau decays (BaBar and Belle) and to those that will join this effort in the future (BES, super-B factories, LHC and future colliders).