论文标题
观察B $^0_ \ MATHRM {S} $ $ \ to $ x（3872）$ ϕ $ decay
Observation of the B$^0_\mathrm{s}$ $\to$ X(3872)$ϕ$ decay
论文作者
论文摘要
使用$ \ sqrt {s} = $ 13 tev的质子 - 普罗顿碰撞的数据样本，对应于CMS实验在2016- 2018年收集的140 fb $^{ - 1} $的集成发光度，b $^0_ \ nathrm {s} $ $ $ $ \ $ \ $ \ $ \ $ x（38872）腐烂到j/$ψ\，π^+π^ - $和k $^+$ k $^ - $分别用于重建X（3872）和$ ϕ $。分支分数$ \ mathcal {b}的产物比率（$ b $^0_ \ MATHRM {s} $ $ \ to $ x（3872）$ x（3872）$ ϕ）\，\ MATHCAL {B}（$ x（3872）$ $\mathcal{B}($B$^0_\mathrm{s}$ $\to$ $ψ$(2S)$ϕ)\,\mathcal{B}(ψ$(2S) $\to$ J/$ψ\,π^+π^-)$ is measured to be (2.21 $\pm$ 0.29 (stat) $\pm$ 0.17 （SYST））％。比率$ \ m nathcal {b}（$ b $^0_ \ MATHRM {s} $ $ \ to $ x（3872）$ ϕ） / \ Mathcal {b $^{0} $ $^{0} $ $ \ $ \ $ x（3872）k $^0）an $ \ mathcal {b}（$ b $^0_ \ mathrm {s} $ $ \ to $ x（3872）$ ϕ） / \ MATHCAL {B}（$ B $^+$ \ $ \ $ \ $ \ to $ x（3872）K $^+）k $^+）k sill sill Bister shower sill Bigell。这表明与b $^+$相比，x（3872）在b $^0 $和b $^0_ \ mathrm {s} $中衰变中的生产动力学有所不同。报道的观察结果可能对X（3872）粒子的性质开发了新的灯光。
Using a data sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV, corresponding to an integrated luminosity of 140 fb$^{-1}$ collected by the CMS experiment in 2016-2018, the B$^0_\mathrm{s}$ $\to$ X(3872)$ϕ$ decay is observed. Decays into J/$ψ\,π^+π^-$ and K$^+$K$^-$ are used to reconstruct, respectively, the X(3872) and $ϕ$. The ratio of the product of branching fractions $\mathcal{B}($B$^0_\mathrm{s}$ $\to$ X(3872)$ϕ)\,\mathcal{B}($X(3872) $\to$ J$/ψ\,π^+π^-)$ to the product $\mathcal{B}($B$^0_\mathrm{s}$ $\to$ $ψ$(2S)$ϕ)\,\mathcal{B}(ψ$(2S) $\to$ J/$ψ\,π^+π^-)$ is measured to be (2.21 $\pm$ 0.29 (stat) $\pm$ 0.17 (syst))%. The ratio $\mathcal{B}($B$^0_\mathrm{s}$ $\to$ X(3872)$ϕ) / \mathcal{B}($B$^{0}$ $\to$ X(3872)K$^0)$ is found to be consistent with one, while the ratio $\mathcal{B}($B$^0_\mathrm{s}$ $\to$ X(3872)$ϕ) / \mathcal{B}($B$^+$ $\to$ X(3872)K$^+)$ is two times smaller. This suggests a difference in the production dynamics of the X(3872) in B$^0$ and B$^0_\mathrm{s}$ meson decays compared to B$^+$. The reported observation may shed new light on the nature of the X(3872) particle.
