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arXiv 0807.4119hep-ex
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B->K(*)1 + 1-衰变中的直接CP、轻子味和同位旋不对称性

Direct CP, Lepton Flavor and Isospin Asymmetries in the Decays B->K(*)l+l-

The BABAR Collaboration, B. Aubert

摘要:

我们测量了稀有衰变B->K(*)l+l-的速率不对称性,其中l+l-是e+e-或mu+mu-,使用在PEP-II e+e-对撞机上用Babar探测器收集的3.84亿个BBbar事件的样本。我们没有发现直接CP或轻子味不对称的证据。对于J/psi共振以下的双轻子质量,我们发现了B->Kl+l-和B->K*l+l-中出乎意料的大的同位旋不对称性的证据,它们与标准模型的预期分别相差3.2 sigma和2.7 sigma,包括系统不确定性。

英文摘要:

We measure rate asymmetries for the rare decays B->K(*)l+l-, where l+l- is either e+e- or mu+mu-, using a sample of 384 million BBbar events collected with the Babar detector at the PEP-II e+e- collider. We find no evidence for direct CP or lepton-flavor asymmetries. For dilepton masses below the J/psi resonance, we find evidence for unexpectedly large isospin asymmetries in both B->Kl+l- and B->K*l+l-, which differ respectively by 3.2 sigma and 2.7 sigma, including systematic uncertainties, from the Standard Model expectations.

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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