From an analysis of the ionisation energy loss of charged particles selected from a sample of 147926 e+e−→τ+τ− candidates recorded in the OPAL detector at e+e− centre-of-mass energies near the Z0 resonance, we determine the branching ratios: where the (π0) notation refers to decay modes with or without an accompanying π0. The final states occurring through τ−→ντK−K0S(π0) are treated as background in this analysis. We also examine the resonant structure of τ−→ντK−π−π+ candidates. Under the assumption that the resonant structure is dominated by the K1 resonances, we determine:
In all results, the first uncertainties are statistical and the second are systematic.