Measurement of tau decays into three charged pions (original) (raw)

Abstract

sparkles

AI

We report a study of the decay process \\tau- \to \pi^- \pi^+ \pi^- \\nu_\tau using the ARGUS detector at the DORIS II storage ring. Tau pairs were produced via e+e- annihilation at center-of-mass energies near 10 GeV, yielding approximately 1,700 observed events. This corresponds to a branching ratio of (5.6 \pm 0.7)%. The dominant decay mode exhibits a resonance near 1.10 GeV/c², consistent with the A1 meson characteristics. The investigation provides insights into the weak axial-vector hadronic current and contributes to the understanding of tau decays.

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