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Study of Time-Dependent CP Asymmetries with Partial Reconstruction of B -> D*+ pi-

The BABAR Collaboration·B. Aubert
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Abstract

We present a preliminary measurement of the time-dependent CP asymmetries in decays of neutral B mesons to the final states D*pi using approximately 82 million BBbar events collected by the BaBar experiment at the PEPII storage ring. Events containing these decays are selected with a partial reconstruction technique, in which only the high momentum pion and the low momentum pion from the D* decay are reconstructed. The flavor of the other B meson in the event is tagged using the information from kaon and lepton candidates. We measure the time-dependent CP asymmetry A = -0.063 +/- 0.024 (stat.) +/- 0.017 (syst.). We interpret these results in terms of the angles of the unitarity triangle to set a bound on |sin(2 beta + gamma)|.

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The BABAR Collaboration, B. Aubert. 2003-07-15. Study of Time-Dependent CP Asymmetries with Partial Reconstruction of B -> D*+ pi-. https://arxiv.org/abs/hep-ex/0307036

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