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arXiv · hep-ph/0510301

Extracting the unitarity angle gamma in Bs to D0 h0, D0bar h0 Decays

Abstract

The recently observed color-suppressed B0bar to D0 pi0, D0 eta, D0 eta', Ds+ K-, D0 K0bar, D0 rho0 and D0 omega decay modes all have rates larger than expected. The color-suppressed Bs to D0 phi, D0bar phi modes, which were suggested for the extraction of the unitarity angle gamma in the Gronau-London method, could be larger than the previous estimation by one order of magnitude. Several new theoretical clean modes in Bs decays are suggested for the extraction of gamma. The proposed Bs to D0 h0, D0bar h0 decay modes with h0 = pi0, eta, eta', rho0, omega in addition to h0 = phi are free from penguin contributions. Their decay rates can be estimated from the observed color-suppressed B0bar to D0 h0 rates through SU(3) symmetry. A combined study of these D0 h0, D0bar h0 modes in addition to the D0 phi, D0bar phi modes is useful in the extraction of gamma in the Bs system without involving the Bs-Bsbar mixing. Since the b to u and b to c transitions belong to the same topological diagram, the relative strong phase is likely to be small. In this case, the CP asymmetries are suppressed and the untagged rates are very useful in the gamma extraction.

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BibTeXRIS

Chun-Khiang Chua. 2005-11-17. Extracting the unitarity angle gamma in Bs to D0 h0, D0bar h0 Decays. https://doi.org/10.1016/j.physletb.2005.11.047

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