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arXiv 0807.4226hep-ex
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B0 -> pi+ pi-,B0-> K+ pi-,B0-> pi0 pi0,B0-> K0 pi0中CP不对称性和分支分数的测量及B -> pi π衰变的同位旋分析

Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays

The BABAR Collaboration, B. Aubert

摘要:

我们提出了在衰变B 0-> pi+ pi-,B 0-> K+ pi-,B 0-> pi 0 pi 0和B 0-> K 0 pi 0中CP破坏不对称性和分支分数的改进测量的初步结果。此更新包括在SLAC的非对称PEP-II B介子工厂的BaBar实验在Y(4S)共振处获得的所有数据,对应于4.67 +- 5百万个BBbar对。我们发现Spipi = -0.68 +-0.10 +-0.03,Cpipi = -0.25 +-0.08 +-0.02,AKpi = -0.107 +-0.016 +0.006-0.004,Cpi 0 pi 0 = -0.43 +-0.26 +-0.05,BF(B 0-> pi 0 pi 0)=(1.83 +- 0.21 +- 0.13)x 10^-6,BF(B 0-> K 0 pi 0)=(10.1 +- 0.6 +- 0.4)x 10^-6,其中第一个误差是统计误差,第二个误差是系统误差。我们观察到CP破坏,在B 0-> pi+ pi-中显著性为6.7 sigma,在B 0-> K+ pi-中显著性为6.1 sigma。对幺正三角角α的约束由所有B -> pipi速率和不对称性之间的同位旋关系确定。

英文摘要:

We present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, and B0 -> K0 pi0. This update includes all data taken at the Y(4S) resonance by the BaBar experiment at the asymmetric PEP-II B-meson factory at SLAC, corresponding to 467 +- 5 million BBbar pairs. We find Spipi = -0.68 +- 0.10 +- 0.03, Cpipi = -0.25 +- 0.08 +- 0.02, AKpi = -0.107 +- 0.016 +0.006-0.004, Cpi0pi0 = -0.43 +- 0.26 +- 0.05, BF(B0 -> pi0 pi0) = (1.83 +- 0.21 +- 0.13) x 10^-6, BF(B0 -> K0 pi0) = (10.1 +- 0.6 +- 0.4) x 10^-6, where the first error is statistical and the second is systematic. We observe CP violation with a significance of 6.7 sigma in B0 -> pi+ pi- and 6.1 sigma in B0 -> K+ pi-. Constraints on the Unitarity Triangle angle alpha are determined from the isospin relation between all B -> pipi rates and asymmetries.

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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