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Search for the rare decay B0-->tau+tau- at BABAR
B Aubert1, R Barate, D Boutigny
1Laboratoire de Physique des Particules, F-74941 Annecy-le-Vieux, France.
Physical Review Letters
|August 16, 2006
Summary
Researchers searched for the rare B0 to tau+tau- decay using BABAR data. No evidence was found, setting an upper limit on this decay
Area of Science:
- Particle Physics
- High-Energy Physics
- Standard Model Extensions
Background:
- The decay B0 to tau+tau- is a rare process predicted by the Standard Model.
- Certain new physics models suggest enhanced rates for this decay.
Purpose of the Study:
- To search for the rare decay B0 to tau+tau-.
- To constrain theoretical models by setting an upper limit on the branching fraction.
Main Methods:
- Analysis of a large dataset of Upsilon(4S) decays collected by the BABAR detector.
- Reconstruction of one neutral B meson and investigation of the rest of the event for the signal decay.
Main Results:
- No significant evidence for the B0 to tau+tau- decay was observed.
- An upper limit on the branching fraction was established: Beta(B0->tau+tau-)<4.1x10(-3) at the 90% confidence level.
Conclusions:
- The results are consistent with the Standard Model prediction of a very small branching fraction.
- The findings place constraints on extensions to the Standard Model that predict larger rates for this decay.
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