Nikhef National Institute for Subatomic Physics, Amsterdam, The Netherlands.
Phys Rev Lett. 2013 May 24;110(21):211801. doi: 10.1103/PhysRevLett.110.211801. Epub 2013 May 21.
A search for the decays B(0)((s))→μ(+)μ(-)μ(+)μ(-) and B(0)→μ(+)μ(-)μ(+)μ(-) is performed using data, corresponding to an integrated luminosity of 1.0 fb(-1), collected with the LHCb detector in 2011. The number of candidates observed is consistent with the expected background and, assuming phase-space models of the decays, limits on the branching fractions are set: B(B(s)(0)→μ(+)μ(-)μ(+)μ(-))<1.6(1.2)×10(-8) and B(B(0)→μ(+)μ(-)μ(+)μ(-))<6.6(5.3)×10(-9) at 95% (90%) confidence level. In addition, limits are set in the context of a supersymmetric model which allows for the B((s))(0) meson to decay into a scalar (S) and pseudoscalar particle (P), where S and P have masses of 2.5 GeV/c and 214.3 MeV/c, respectively, both resonances decay into μ(+)μ(-). The branching fraction limits for these decays are B(B(s)(0)→SP)<1.6(1.2)×10(-8) and B(B(0)→SP)<6.3(5.1)×10(-9) at 95% (90%) confidence level.
使用 LHCb 探测器在 2011 年收集的 1.0 fb^(-1)积分亮度的数据，对 B(0)((s))→μ(+)μ(-)μ(+)μ(-) 和 B(0)→μ(+)μ(-)μ(+)μ(-) 的衰变进行了搜索。观察到的候选数与预期的背景相符，并且假设衰变的相空间模型，对分支比设定了限制：B(B(s)(0)→μ(+)μ(-)μ(+)μ(-))<1.6(1.2)×10^(-8) 和 B(B(0)→μ(+)μ(-)μ(+)μ(-))<6.6(5.3)×10^(-9)，置信水平为 95%（90%）。此外，在允许 B((s))(0) 介子衰变为标量 (S) 和赝标量粒子 (P) 的超对称模型背景下，也设定了限制，其中 S 和 P 的质量分别为 2.5 GeV/c 和 214.3 MeV/c，两个共振都衰变为 μ(+)μ(-)。这些衰变的分支比限制为 B(B(s)(0)→SP)<1.6(1.2)×10^(-8) 和 B(B(0)→SP)<6.3(5.1)×10^(-9)，置信水平为 95%（90%）。
