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Updated: Apr 16, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Lepton flavor violation in B decays?
Sheldon L Glashow1, Diego Guadagnoli2, Kenneth Lane1
1Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
Abstract:
The LHCb Collaboration's measurement of R_{K}=B(B^{+}→K^{+}μ^{+}μ^{-})/B(B^{+}→K^{+}e^{+}e^{-}) lies 2.6σ below the Standard Model prediction. Several groups suggest this deficit to result from new lepton nonuniversal interactions of muons. But nonuniversal leptonic interactions imply lepton flavor violation in B decays at rates much larger than are expected in the Standard Model. A simple model shows that these rates could lie just below current limits. An interesting consequence of our model, that B(B_{s}→μ^{+}μ^{-})_{exp}/B(B_{s}→μ^{+}μ^{-})_{SM}≅R_{K}≅0.75, is compatible with recent measurements of these rates. We stress the importance of searches for lepton flavor violations, especially for B→Kμe, Kμτ, and B_{s}→μe, μτ.
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