Related Experiment Videos
Search for B^{+}→K^{+}τ^{+}τ^{-} at the BaBar Experiment.
J P Lees1, V Poireau1, V Tisserand1
1Laboratoire d'Annecy-le-Vieux de Physique des Particules (LAPP), Université de Savoie, CNRS/IN2P3, F-74941 Annecy-Le-Vieux, France.
Physical Review Letters
|February 4, 2017
Summary
Researchers investigated the rare B+→K+τ+τ− decay using BABAR experiment data. No significant signal was observed, establishing an upper limit for this flavor-changing neutral current process.
Area of Science:
- Particle Physics
- High-Energy Physics
- Experimental Physics
Background:
- Flavor-changing neutral current (FCNC) processes are rare in the Standard Model.
- The B+→K+τ+τ− decay is a theoretically interesting FCNC process.
- Experimental searches for such rare decays provide crucial tests of the Standard Model.
Purpose of the Study:
- To search for the rare FCNC process B+→K+τ+τ−.
- To set an upper limit on the branching fraction of this decay.
- To constrain new physics models beyond the Standard Model.
Main Methods:
- Utilized data from the BABAR experiment, corresponding to 424 fb−1 integrated luminosity.
- Reconstructed one B meson in hadronic decay modes and searched for B+→K+τ+τ− in the rest of the event.
- Required each tau lepton to decay leptonically (to electron or muon and neutrinos).
Main Results:
- No evidence for a signal of the B+→K+τ+τ− decay was found.
- An upper limit at the 90% confidence level was set: B(B+→K+τ+τ−)<2.25×10−3.
Conclusions:
- The experimental search places constraints on the branching fraction of the B+→K+τ+τ− decay.
- The results are consistent with Standard Model predictions, which indicate a very small branching fraction for this decay.
- This measurement contributes to the ongoing effort to probe New Physics scenarios.