Charged kaon production in 3-prong τ decays in DELPHI

Abstract

The production of charged kaons in the three-prong decay of the τ is studied using the data collected in the DELPHI detector during the LEP-1 data taking between 1992 and 1995. Algorithms for the reconstruction of the τ decay vertex and the charged kaon identification in the Barrel RICH are presented. With these tools we tag τ − → K −K +π −ν τ and τ − → K −π +π −π τ decays on an event-by-event basis. Preliminary results for the inclusive branching ratios τ − → K −K +π −ν τ and τ − → K −π +π −ν τ determined from the 1994 data sample are presented.