Direct limits on the B-s(0) oscillation frequency
Direct limits on the B-s(0) oscillation frequency
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DOI：
10.1103/physrevlett.97.021802
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发表时间：
2006-03
影响因子：
8.6
通讯作者：
D0 Collaboration;V. Abazov;E. al.
中科院分区：
文献类型：
--
作者：
D0 Collaboration;V. Abazov;E. al.
我们利用2002- 2006年费米实验室Tevatron对撞机第2次运行期间\dzer实验收集的大量$B^0_s$半光子衰减样本，报告了$B^0_s$振荡频率的第一个直接双边边界，这些样本对应于大约1 fb $^{-1}$的综合光度。使用反侧标记技术发现了\bs介子在产生时的味道（即$B^0_s$或$\bar{B}^0_s$），并且从部分重建衰变中的μ子的电荷确定了衰变时的味道$\bs\to \mu^{+}D_{s}^{-}X$, $D_{s}^{-}\to \phi \pi^{-}$, $\phi\to K^{+}K^{-}$。对振荡频率$\Delta m_s$进行似然扫描，得到最可能的值为19 ps $^{-1}$，在90的范围为$17 < \Delta m_s < 21$ ps $^{-1}$% C.L. At $\Delta m_s=19$ ps$^{-1}$, the amplitude method yields a result that deviates from the hypothesis of an oscillation amplitude of zero by 2.5 standard deviations, corresponding to a two-sided C.L. of 1%.
We report the first direct two-sided bound on the $B^0_s$ oscillation frequency using a large sample of $B^0_s$ semileptonic decays corresponding to approximately 1 fb$^{-1}$ of integrated luminosity collected by the \dzer\ experiment in 2002--2006 during Run II of the Fermilab Tevatron Collider. The flavor (i.e., $B^0_s$ or $\bar{B}^0_s$) of the \bs meson at the time of production was found using an opposite-side tagging technique, and the flavor at the time of decay was determined from the charge of the muon in the partially reconstructed decay $\bs\to \mu^{+}D_{s}^{-}X$, $D_{s}^{-}\to \phi \pi^{-}$, $\phi\to K^{+}K^{-}$. A likelihood scan over the oscillation frequency, $\Delta m_s$, gives a most probable value of 19 ps$^{-1}$ and a range of $17 < \Delta m_s < 21$ ps$^{-1}$ at the 90% C.L. At $\Delta m_s=19$ ps$^{-1}$, the amplitude method yields a result that deviates from the hypothesis of an oscillation amplitude of zero by 2.5 standard deviations, corresponding to a two-sided C.L. of 1%.