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Updated: Jun 26, 2026
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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Search for lepton flavor violation in upsilon decays
Physical Review Letters
|December 31, 2008
Summary
This study searched for lepton flavor violation in bottomonium decays, specifically Upsilon(nS) to mu tau. No evidence was found, setting upper limits on these rare processes.
Area of Science:
- Particle Physics
- High Energy Physics
- Quantum Field Theory
Background:
- Lepton flavor violation (LFV) is a key signature for new physics beyond the Standard Model.
- The bottomonium system offers a unique platform to search for LFV due to its mass and quark content.
Purpose of the Study:
- To search for lepton flavor violating decays Upsilon(nS) -> mu tau (n=1, 2, 3).
- To set limits on the branching fractions of these LFV decays.
Main Methods:
- Utilized data from the CLEO III detector.
- Identified tau leptons via their nu_tau nu_e e decay channel.
- Employed multidimensional likelihood fitting with probability density functions from independent data.
Main Results:
- Established 95% confidence level (C.L.) upper limits on LFV branching fractions for Upsilon(1S), Upsilon(2S), and Upsilon(3S) decays.
- The search found no significant signal for LFV.
Conclusions:
- The results constrain parameters in extensions of the Standard Model.
- Exclusion plots were generated for the energy scale and effective LFV coupling of hypothetical new interactions.
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