We search for lepton-flavor and lepton-number-violating. Τ decays into a lepton (ℓ= electron or muon) and two charged mesons (h,h'=π± or K±) using 854 fb-1 of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain 90% confidence level upper limits on the. Τ→ℓhh' branching fractions in the range. (2.0-8.4)×10-8. These results improve upon our previously published upper limits by factors of about 1.8 on average.
|Number of pages||8|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2013 Feb 26|