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arXiv 0807.2408hep-ex
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B -> D*K衰变的分支比和CP破坏不对称性的测量

Measurement of Ratios of Branching Fractions and CP-Violating Asymmetries of B -> D*K Decays

The BABAR Collaboration, B. Aubert

摘要:

我们报告了B -> D*K衰变与D* 衰变到D π 0或D γ的研究,使用383 * 10**6 B Bbar对收集在Uppersonal(4S)共振与BaBar探测器在SLAC PEP-II B工厂。所研究的D介子衰变包括非CP模(Kpi)、CP偶模(K+K-,pi^+pi^-)和CP奇模(KS pi 0,KS phi,KS omega)。我们测量了衰变的分支分数与CP本征模态和风味特异态的比值(R * CP+-)以及CP不对称性(A* CP+-)。这些测量对幺正三角角γ敏感。我们得到A*_{CP+} = -0.11 pm 0.09 pm 0.01,R*_{CP+} = ~1.31 pm 0.13 pm 0.04,A*_{CP-} = 0.06 pm 0.10 pm 0.02,R*_{CP-} = ~1.10 pm 0.12 pm 0.04,其中第一个误差是统计误差,第二个误差是系统误差。将我们的结果转换为广泛用于相关测量的替代参数化,我们得到x*_{+}=0.11 pm 0.06 pm 0.02和x*_{-} = 0.00 pm 0.06 pm 0.02。在风味特定模式D -> K π或B -> D* π衰变中均未发现显著的CP破坏电荷不对称性。

英文摘要:

We report a study of B -> D*K decays with D* decaying to D pi0 or D gamma, using 383 * 10**6 B Bbar pairs collected at the Upsilon(4S) resonance with the BaBar detector at the SLAC PEP-II B-Factory. The D meson decays under study include a non-CP mode (Kpi), CP-even modes (K+K-, pi^+pi^-) and CP-odd modes (KS pi0, KS phi, KS omega). We measure ratios (R*_{CP+-}) of branching fractions of decays to CP eigenmode states and to flavor-specific states as well as CP asymmetries (A*_{CP+-}). These measurements are sensitive to the unitarity triangle angle gamma. We obtain A*_{CP+} = -0.11 pm 0.09 pm 0.01, R*_{CP+} = ~1.31 pm 0.13 pm 0.04, and A*_{CP-} = 0.06 pm 0.10 pm 0.02, R*_{CP-} = ~1.10 pm 0.12 pm 0.04, where the first error is statistical and the second error is systematic. Translating our results into an alternative parametrization, widely used for related measurements, we obtain x*_{+}=0.11 pm 0.06 pm 0.02 and x*_{-} = 0.00 pm 0.06 pm 0.02. No significant CP-violating charge asymmetry is found in either the flavor-specific mode D -> K pi or in B -> D* pi decays.

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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