Nikhef National Institute for Subatomic Physics, Amsterdam, The Netherlands.
Phys Rev Lett. 2013 Oct 4;111(14):141801. doi: 10.1103/PhysRevLett.111.141801. Epub 2013 Sep 30.
A search for the lepton-flavor-violating decays B(s)0→e(±)μ(∓) and B0→e(±)μ(∓) is performed with a data sample, corresponding to an integrated luminosity of 1.0 fb(-1) of pp collisions at √s=7 TeV, collected by the LHCb experiment. The observed number of B(s)0→e(±)μ(∓) and B0→e(±)μ(∓) candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(B(s)0→e(±)μ(∓))<1.1(1.4)×10(-8) and B(B0→e(±)μ(∓))<2.8(3.7)×10(-9) at 90% (95%) confidence level (C.L.). These limits are a factor of 20 lower than those set by previous experiments. Lower bounds on the Pati-Salam leptoquark masses are also calculated, M(LQ)(B(s)0→e(±)μ(∓))>101 TeV/c(2) and M(LQ)(B0→e(±)μ(∓))>126 TeV/c(2) at 95% C.L., and are a factor of 2 higher than the previous bounds.
使用 LHCb 实验在 √s=7 TeV 的 pp 碰撞中收集的 1.0 fb(-1) 积分亮度数据样本，搜索了轻子味破坏衰变 B(s)0→e(±)μ(∓) 和 B0→e(±)μ(∓)。观察到的 B(s)0→e(±)μ(∓) 和 B0→e(±)μ(∓) 候选数与背景预期一致。在 90%（95%）置信水平（C.L.）下，这两种衰变的分支比上限分别为 B(B(s)0→e(±)μ(∓))<1.1(1.4)×10(-8) 和 B(B0→e(±)μ(∓))<2.8(3.7)×10(-9)。这些限制比以前的实验低 20 倍。还计算了 Pati-Salam 轻夸克质量的下限，在 95% C.L. 下，LQ(B(s)0→e(±)μ(∓))>101 TeV/c(2) 和 LQ(B0→e(±)μ(∓))>126 TeV/c(2)，比以前的界限高 2 倍。
