STRUCTURE FUNCTIONS IN TAU DECAYS

Semileptonic decays of polarized tau leptons are investigated and the most general angular distribution of two and three meson final states is derived. Emphasis is put on tau studies in electron positron annihilation where the neutrino escapes detection and the tau restframe cannot be reconstructed. It is shown that the most general distribution can be characterized by 16 structure functions, most of which can be determined in currently ongoing high statistics experiments. Of particular interest for the three meson case are the distribution of the normal to the Dalitz plane and the distribution around this normal. Predictions for the structure functions are given for the two and three pion case and for K*(--> Kpi). Implications for an experiment where the tau restframe could be reconstructed are also considered.