A study of three-prong tau decays with charged kaons

Abstract

Abstract.

From an analysis of the ionisation energy loss of charged particles selected from a sample of 147926 \({\rm e}^+{\rm e}^- \!\!\rightarrow\! \tau^+\tau^-\) candidates recorded in the OPAL detector at \({\rm e}^+{\rm e}^-\) centre-of-mass energies near the \({\rm Z}^0\) resonance, we determine the branching ratios: where the \((\pi^0)\) notation refers to decay modes with or without an accompanying \(\pi^0\). The final states occurring through \(\tau^- \rightarrow \nu_\tau{\rm K}^-{\rm K}^0_{\rm S} (\pi^0)\) are treated as background in this analysis. We also examine the resonant structure of \(\tau^- \!\!\rightarrow\!\! \,\nu_\tau\,{\rm K}^-\pi^-\pi^+\) candidates. Under the assumption that the resonant structure is dominated by the K\(_1\) resonances, we determine: In all results, the first uncertainties are statistical and the second are systematic.