论文标题
搜索$ b^{0} \ to k_s^{0} k_s^{0}γ$衰减在belle
Search for $B^{0} \to K_S^{0}K_S^{0}γ$ decays at Belle
论文作者
论文摘要
我们首次使用$ b^0 \ rightArrow k_s^0 k_s^0γ$的首次搜索使用$ 772 \ times 10^6 $ $ $ b \ bar {b} $ pairs在Kekb akkb yemmetric-enerergy $ e^+ e^+ clider中收集的完整数据样本。我们没有在$ k_s^0 $ - pair不变质量范围1 Gev/$ c^2 <m_ {k_s^0 k_s^0} <$ 3 gev/$ c^2 $中观察到任何具有统计学意义的信号产量，并将以下上限设置为90％的置信度：$ \ \ \ \ \ \ \ \ \ \ k^0 \ k_s^0 \ k_ k^0 \ k k^0 \ k k^0. 5.8 \ times10^{ - 7} $，$ \ MATHCAL {b}（b^0 \ tof_2γ）\ times \ times \ Mathcal {b}（f_2（f_2（1270）\ to K_S^0 K_S^0 K_S^0） f_2^{\ prime}γ）\ times \ times \ mathcal {b}（f_2^{\ prime}（1525）\ to k_s^0 k_s^0）<2.1 \ 2.1 \ times10^{ - 7} $。此外，在$ b^0 \ rightArrow k_s^0 k_s^0γ$分支分数$ m_s {k_s^0 k_s^0} $的范围内也设置了90％的上限上限。
We report the first search for the penguin-dominated process $B^0 \rightarrow K_S^0 K_S^0 γ$ using the full data sample of $772\times 10^6$ $B\bar{B}$ pairs collected with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. We do not observe any statistically significant signal yield in the $K_S^0$-pair invariant mass range 1 GeV/$c^2 < M_{K_S^0 K_S^0} < $ 3 GeV/$c^2$, and set the following upper limits at 90% confidence level: $\mathcal{B}(B^0 \to K_S^0 K_S^0 γ) < 5.8\times10^{-7}$, $\mathcal{B}(B^0 \to f_2 γ)\times \mathcal{B}(f_2 (1270) \to K_S^0 K_S^0 ) < 3.1\times10^{-7}$, and $\mathcal{B}(B^0 \to f_2^{\prime} γ)\times \mathcal{B}(f_2^{\prime} (1525) \to K_S^0 K_S^0 ) < 2.1\times10^{-7}$. Further, 90% confidence upper limits have also been set in the range of [0.7-2.9]$\times10^{-7}$ on the $B^0 \rightarrow K_S^0 K_S^0 γ$ branching fraction in bins of $M_{K_S^0 K_S^0}$.
