Neutrinoless tau-lepton decays into either three leptons (τ- → ℓ1-ℓ2ℓ3) or one lepton and one KS0 meson(τ- → ℓ- KS0) where lepton ℓ means either an electron or muon, have been searched for using 48.6 fb-1 of data collected with the Belle detector at the KEKB e+e- collider. No evidence for candidate decays are found in any channel. Therefore we set 90% confidence level upper limits on the branching fraction for 8 different decay modes. These limits are more stringent than those set previously and reach to the 10-7 level.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Nuclear and High Energy Physics