Abstract
We report a study of the decay τ−→τ−τ+τ− v τ using the ARGUS detector at the DORIS II storage ring. Tau pairs were produced bye + e − annihilation at centre-of-mass energies near 10 GeV. We have observed about 1,700 events, corresponding to a branching ratio for τ−→τ−τ+τ− v τ of (5.6±0.7)%. The dominant mode for this decay is observed to beρ 0π− in aJ p=1+ spin state. Theρ 0π− mass spectrum shows a broad enhancement near 1.10 GeV/c2, which has the properties expected for theA 1.
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Supported by the Bundesministerium für Forschung und Technologie, FRG
Supported by the Natural Sciences and Engineering Research Council, Canada
Supported by the U.S. National Science Foundation, USA
Supported in part by the Internationales Büro KfA, Jülich and DESY, Hamburg, FRG
Supported by the Swedish Research Council, Sweden
Supported by the U.S. Department of Energy, under contract DE-AS09-80ER10690, USA
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ARGUS Collaboration., Albrecht, H., Binder, U. et al. Measurement of tau decays into three charged pions. Z. Phys. C - Particles and Fields 33, 7–12 (1986). https://doi.org/10.1007/BF01410447
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DOI: https://doi.org/10.1007/BF01410447