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Extracting γfrom Bd(t) -> D(*)+ D(*)- and Bd -> Ds(*)+ D(*)- Decays

Alakabha Datta·David London
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Abstract

We show that the CP phase γcan be obtained from measurements of Bd(t) -> D(*)+ D(*)- and Bd -> Ds(*)+ D(*)-. These decays are related by flavor SU(3) in the limit where spectator-quark contributions are small. If the pseudoscalar-pseudoscalar decays Bd(t) -> D+ D- and Bd -> Ds+ D- are used, the leading-order SU(3)-breaking effect is f_Ds/f_D. The dependence on decay constants can be removed by using a double ratio involving two helicity states of the vector-vector decays Bd(t) -> D*+ D*- and Bd -> Ds*+ D*-. In this case the theoretical error arising from all sources is in the range 5-10%.

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Alakabha Datta, David London. 2003-12-05. Extracting γfrom Bd(t) -> D(*)+ D(*)- and Bd -> Ds(*)+ D(*)- Decays. https://doi.org/10.1016/j.physletb.2003.12.048

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