We present a study of the decay τ- → KS π- ντ using a 351 fb-1 data sample collected with the Belle detector. The analysis is based on 53, 110 lepton-tagged signal events. The measured branching fraction B (τ- → KS π- ντ) = (0.404 ± 0.002 (stat .) ± 0.013 (syst .)) % is consistent with the world average value and has better accuracy. An analysis of the KS π- invariant mass spectrum reveals contributions from the K* (892)- as well as other states. For the first time the K* (892)- mass and width have been measured in τ decay: M (K* (892)-) = (895.47 ± 0.20 (stat .) ± 0.44 (syst .) ± 0.59 (mod .)) MeV / c2, Γ (K* (892)-) = (46.2 ± 0.6 (stat .) ± 1.0 (syst .) ± 0.7 (mod .)) MeV. The K* (892)- mass is significantly different from the current world average value.
|Original language||English (US)|
|Number of pages||9|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - Oct 11 2007|
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics