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New bound on penguin pollution in B^0(t) --> pi^+ pi^-

A. K. Giri·R. Mohanta
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Abstract

In the presence of penguin contributions, the indirect CP asymmetry in B^0(t) --> pi^+ pi^- measures sin 2alpha_{eff}, where alpha_{eff} deviates from the true value of the CKM phase alpha by an amount theta, i.e. alpha_{eff} = alpha + theta. Using the measured value of direct CP asymmetry in B^0(t) --> pi^+ pi^-, we derive new bound on |2 theta|.

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A. K. Giri, R. Mohanta. 2002-08-06. New bound on penguin pollution in B^0(t) --> pi^+ pi^-. https://arxiv.org/abs/hep-ph/0207249

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