论文标题
$ b^{+} \toπ^{+}π^{0}π^{0} $分支分数和\ textit {cp}不对称的第一个测量
First measurement of the $B^{+}\toπ^{+}π^{0}π^{0}$ branching fraction and \textit{CP} asymmetry
论文作者
论文摘要
我们研究$ b^{+} \ toπ^{+}π^{0}π^{0} $，使用711 $ \ rm {fb}^{ - 1} $在$υ（4S）$ resonance在kekb asmmetric $ enerergy $ eNerergy-enerergy-enerergy-enerergy-enerergy-enerergy-enerergy-enerergy-enerergy-enerergy-eNerergy}的数据中收集的数据的数据的数据。我们测量$（19.0 \ pm 1.5 \ pm 1.4）\ times 10^{ - 6} $的包含分支分数和包含的\ textit {cp} $（9.2 \ pm 6.8 \ pm 0.7）\％$ $的不对称{和a $ b^{+} \ toρ（770）^{+}π^{0} $分支$（11.2 \ pm 1.1 \ pm 0.9^{+0.8} {+0.8} _ { - 1.6}） ρ（1450）^{+}π^{0} $。我们介绍了$π^{0}π^{0} $质量谱的第一个观察到1 GEV/$ C^{2} $，其显着性为6.4 $σ$，并测量分支分数为$（6.9 \ pm 0.9 \ pm 0.9 \ pm 0.6 \ pm 0.6 \ pm 0.6 \ pm 0.6）\ times \ tims 10^^{ - 6} $。我们还报告了该结构中局部\ textit {cp}的测量值。
We study $B^{+}\to π^{+}π^{0}π^{0}$ using 711 $\rm{fb}^{-1}$ of data collected at the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider. We measure an inclusive branching fraction of $(19.0\pm 1.5\pm 1.4)\times 10^{-6}$ and an inclusive \textit{CP} asymmetry of $(9.2 \pm 6.8 \pm 0.7)\%$, where the first uncertainties are statistical and the second are systematic; and a $B^{+}\to ρ(770)^{+}π^{0}$ branching fraction of $(11.2\pm 1.1\pm 0.9 ^{+0.8}_{-1.6})\times 10^{-6}$, where the third uncertainty is due to possible interference with $B^{+}\to ρ(1450)^{+}π^{0}$. We present the first observation of a structure around 1 GeV/$c^{2}$ in the $π^{0}π^{0}$ mass spectrum, with a significance of 6.4$σ$, and measure a branching fraction to be $(6.9\pm 0.9\pm 0.6)\times 10^{-6}$. We also report a measurement of local \textit{CP} asymmetry in this structure.
