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Measurements of sin2alpha/phi2 from B -> pipi, rhopi and rhorho modes

A. Bevan
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Abstract

B meson decays involving b -> u transitions are sensitive to the unitarity triangle angle alpha (or phi2). The BaBar and Belle experiments have studied B-meson decays to pipi, rhopi and rhorho final states. It is possible to combine these measurements to constrain alpha with a precision of O(10 degrees) and a central value of approximately 100 degrees. These results are consistent with Standard Model expectations.

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A. Bevan. 2004-11-30. Measurements of sin2alpha/phi2 from B -> pipi, rhopi and rhorho modes. https://arxiv.org/abs/hep-ex/0411090

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