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Observation of Ds+ K- and evidence for Ds+ pi- final states in neutral B decays

P. Krokovny·The Belle Collaboration
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Abstract

We report the first observation of a B meson decay that is not accessible by a direct spectator process. The channel B0bar -> Ds+ K- is found in a sample of 85 timse 10^6 B Bbar events, collected with the Belle detector at KEKB, with a branching fraction Br(B0bar -> Ds+ K-)=(4.6^{+1.2}_{-1.1} +- 1.3) times 10^{-5}. We also obtain evidence for the B0 -> Ds+ pi- decay with branching fraction Br(B0 -> Ds+ pi-)=(2.4^{+1.0}_{-0.8} +- 0.7) times 10^{-5}. This value may be used to extract a model-dependent value of |Vub|.

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P. Krokovny, The Belle Collaboration. 2002-10-16. Observation of Ds+ K- and evidence for Ds+ pi- final states in neutral B decays. https://doi.org/10.1103/physrevlett.89.231804

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