Evidence for the decay τ^-->ν"τωπ^-

Using the ARGUS detector at DORIS II, we have analyzed tau decays into π^-π^-π^+π^0ν"τ. The branching ratio was determined to be (4.2+/-0.5+/-0.9)%. From a study of the three pion sub-system, we find evidence for the decay τ^-->ωπ^-ν"τ with a branching ratio of (1.5+/-0.3+/-0.3)%. The ω...
Ausführliche Beschreibung

Using the ARGUS detector at DORIS II, we have analyzed tau decays into π^-π^-π^+π^0ν"τ. The branching ratio was determined to be (4.2+/-0.5+/-0.9)%. From a study of the three pion sub-system, we find evidence for the decay τ^-->ωπ^-ν"τ with a branching ratio of (1.5+/-0.3+/-0.3)%. The ωπ^- system is found to be predominantly in a J^P=1^- state. There is no evidence for second-class axial-vector currents. The spectral function for the ωπ^- final state is in agreement with a prediction based on CVC and σ"e+"e-->ωπ^0. Ausführliche Beschreibung