Glashow Sheldon L, Guadagnoli Diego, Lane Kenneth
Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
Laboratoire d'Annecy-le-Vieux de Physique Théorique UMR5108, CNRS et Université de Savoie, BP 110, F-74941 Annecy-le-Vieux Cedex, France.
Phys Rev Lett. 2015 Mar 6;114(9):091801. doi: 10.1103/PhysRevLett.114.091801. Epub 2015 Mar 3.
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.
大型强子对撞机底夸克实验合作组对 (R_{K}=B(B^{+}→K^{+}μ^{+}μ^{-})/B(B^{+}→K^{+}e^{+}e^{-})) 的测量结果比标准模型预测低 (2.6\sigma)。几个团队认为这种差异是由新的μ子轻子非普适相互作用导致的。但非普适轻子相互作用意味着在 (B) 衰变中轻子味违反的速率远大于标准模型中的预期。一个简单模型表明这些速率可能刚好低于当前限制。我们模型的一个有趣结果是 (B(B_{s}→μ^{+}μ^{-}){exp}/B(B{s}→μ^{+}μ^{-}){SM}≅R{K}≅0.75)，这与这些速率的近期测量结果相符。我们强调寻找轻子味违反的重要性，特别是对于 (B→Kμe)、(Kμτ) 以及 (B_{s}→μe)、(μτ) 的情况。
