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arXiv · hep-ph/9808493

New Bound on gamma from B^+- -> pi K Decays

M. Neubert·J. L. Rosner
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Abstract

A bound on the angle gamma of the unitarity triangle is derived using experimental information on the CP-averaged branching ratios for the rare decays B^+- -> pi^+- K^0 and B^+- -> pi^0 K^+-. The theoretical description is cleaner than the Fleischer-Mannel analysis of the decays B^+- -> pi^+- K^0 and B^0 -> pi^-+ K^+- in that the two decay rates differ only in a single isospin amplitude, which has a simple structure in the SU(3) limit. As a consequence, electroweak penguin contributions and strong rescattering effects can be taken into account in a model-independent way. The resulting bound excludes values of cos(gamma) around 0.6 and is thus largely complementary to indirect constraints derived from a global analysis of the unitarity triangle.

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M. Neubert, J. L. Rosner. 1998-09-16. New Bound on gamma from B^+- -> pi K Decays. https://doi.org/10.1016/s0370-2693(98)01194-0

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