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Determination of the weak phase gamma=arg(V_ub^*)

Matthias Neubert
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Abstract

Various strategies for extracting or constraining the weak phase gamma with controlled theoretical uncertainties are reviewed. Measurements of the rates for the hadronic decays B^+- -> pi K provide largely model-independent information on gamma. Hadronic uncertainties enter only at the level of nonfactorizable contributions to the decay amplitudes that are power-suppressed in Lambda/m_b and, simultaneously, violate SU(3) flavor symmetry or are doubly Cabibbo suppressed. In addition, these decays have a rich potential for probing physics beyond the Standard Model. Alternative proposals for learning gamma are also discussed briefly.

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Matthias Neubert. 1999-10-28. Determination of the weak phase gamma=arg(V_ub^*). https://arxiv.org/abs/hep-ph/9910530

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