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arXiv · hep-ph/9805508

Fast CP Violation

Yuval Grossman·Jose R. Pelaez·Mihir P. Worah
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Abstract

$B$ flavor tagging will be extensively studied at the asymmetric $B$ factories due to its importance in CP asymmetry measurements. The primary tagging modes are the semileptonic decays of the $b$ (lepton tag), or the hadronic $b \to c (\to s)$ decays (kaon tag). We suggest that looking for time dependent CP asymmetries in events where one $B$ is tagged leptonically and the other one is tagged with a kaon could result in an early detection of CP violation. Although in the Standard Model these asymmetries are expected to be small, $\sim 1%$, they could be measured with about the same amount of data as in the ``gold-plated'' decay $B_d \to ψK_S$. In the presence of physics beyond the Standard Model, these asymmetries could be as large as $\sim 5%$, and the first CP violation signal in the $B$ system may show up in these events. We give explicit examples of new physics scenarios where this occurs.

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Yuval Grossman, Jose R. Pelaez, Mihir P. Worah. 1998-07-20. Fast CP Violation. https://doi.org/10.1103/physrevd.58.096009

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