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arXiv 1002.1352hep-ex
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底强子新的无粲衰变观测

Observation of New Charmless Decays of Bottom Hadrons

Michael J. Morello

摘要:

我们在费米实验室Tevatron的升级对撞机探测器上寻找新的中性$b$ -强子到带电强子对的无魅力衰变。使用对应于1 fb $^{-1}$的积分光度的数据样本,我们报告了\BsKpi衰变的第一次观测,具有$8.2σ$的意义,并测量了$\BR(\BsKpi) = (5.0 \pm 0.7\stat \pm 0.8\syst)\times 10^{-6}$。我们还报道了在\Lbppi和\LbpK通道中首次观测到的无粲重子衰变--$b$,并测量了$\BR(\Lbppi) = (3.5 \pm 0.6\stat \pm 0.9\syst)\times 10^{-6}$和$\BR(\LbpK) = (5.6 \pm 0.8\stat \pm 1.5\syst)\times 10^{-6}$ .没有发现衰变\BdKK和\Bspipi的证据,我们在90%的置信水平下设置了一个改进的上限$\BR(\Bspipi) < 1.2\times 10^{-6}$。使用$\BR(\BdKpi)$作为参考测量所有引用的支化分数。

英文摘要:

We search for new charmless decays of neutral $b$--hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb$^{-1}$ of integrated luminosity, we report the first observation of the \BsKpi decay, with a significance of $8.2σ$, and measure $\BR(\BsKpi) = (5.0 \pm 0.7\stat \pm 0.8\syst)\times 10^{-6}$. We also report the first observation of charmless $b$--baryon decays in the channels \Lbppi and \LbpK with significances of $6.0σ$ and $11.5σ$ respectively, and we measure $\BR(\Lbppi) = (3.5 \pm 0.6\stat \pm 0.9\syst)\times 10^{-6}$ and $\BR(\LbpK) = (5.6 \pm 0.8\stat \pm 1.5\syst)\times 10^{-6}$. No evidence is found for the decays \BdKK and \Bspipi, and we set an improved upper limit $\BR(\Bspipi) < 1.2\times 10^{-6}$ at the 90% confidence level. All quoted branching fractions are measured using $\BR(\BdKpi)$ as a reference.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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