论文标题
在Belle搜索$ b^0 $衰减到无形的最终状态（$+γ$）
Search for $B^0$ Decays to Invisible Final States ($+γ$) at Belle
论文作者
论文摘要
我们将$ b^0 \的搜索报告为\ rm {Invisible} $和$ b^0 \ to \ rm {Invisible}+γ$衰减，其中光子的能量必须大于0.5 GEV。这些结果来自$ 711 \，{\ rm fb}^{ - 1} $数据样本，其中包含$ 772 \ times 10^6 b \ bar {b} $ pairs收集，并在$υ\，（4S）$ resonance附近收集了kekb $ e^+ e^+ e^ - $ e^+ clider的$（4S）$ resonance。我们没有观察到衰减的明显信号，并将其分支分支的上限设置为$ 90 \％$ $ \ Mathcal {b} \，（b^0 \ to \ rm {Invisible}）<7.8 \ times10^7.8 \ times10^{ - 5} $} <1.6 \ times10^{ - 5} $。
We report searches for $B^0\to\rm{invisible}$ and $B^0\to\rm{invisible}+γ$ decays, where the energy of the photon is required to be larger than 0.5 GeV. These results are obtained from a $711\,{\rm fb}^{-1}$ data sample that contains $772 \times 10^6 B\bar{B}$ pairs and was collected near the $Υ\,(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. We observe no significant signal for either decay and set upper limits on their branching fractions at $90\%$ confidence level of $\mathcal{B}\,(B^0\to\rm{invisible}) < 7.8\times10^{-5}$ and $\mathcal{B}\,(B^0\to\rm{invisible}+γ) < 1.6\times10^{-5}$.
