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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Search for charged lepton flavor violation in narrow upsilon decays
J P Lees1, V Poireau, E Prencipe
1Laboratoire d'Annecy-le-Vieux de Physique des Particules, Université de Savoie, CNRS/IN2P3, F-74941 Annecy-Le-Vieux, France.
Physical Review Letters
|May 21, 2010
Summary
This study searched for rare charged-lepton flavor-violating decays of Upsilon mesons. No evidence was found, leading to new limits on new physics beyond the Standard Model.
Area of Science:
- Particle Physics
- High Energy Physics
- Beyond Standard Model Physics
Background:
- Charged-lepton flavor-violating (CLFV) processes are forbidden in the Standard Model.
- Several theories beyond the Standard Model, such as supersymmetry and leptoquark models, predict enhanced CLFV rates.
Purpose of the Study:
- To search for CLFV decays of Upsilon(2S) and Upsilon(3S) resonances.
- To constrain the parameters of new physics models by setting limits on CLFV branching fractions.
Main Methods:
- Analysis of 99x10^6 Upsilon(2S) and 117x10^6 Upsilon(3S) decays collected by the BABAR detector.
- Searched for Upsilon(nS) -> e+/- tau-/+ and Upsilon(nS) -> mu+/- tau-/+ (n=2,3) decay channels.
Main Results:
- Upper limits on branching fractions for Upsilon(nS) -> e+/- tau-/+ and Upsilon(nS) -> mu+/- tau-/+ were set at the 10^-6 level.
- These results provide stringent constraints on CLFV processes.
Conclusions:
- The absence of observed CLFV decays places lower limits of approximately 1 TeV on the mass scale of CLFV effective operators.
- This search contributes to constraining new physics scenarios beyond the Standard Model.
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