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A Measurement of Semileptonic B Decays to Narrow Orbitally-Excited Charm Mesons

The OPAL collaboration·G. Abbiendi
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Abstract

The decay chain b -> Bbar -> D^{**0} l nu X, D^{**0} -> D^{*+} pi^-, D^{*+} -> D^0 pi^+, D^0 ->(Kpi or K3pi) is identified in a sample of 3.9 million hadronic Z decays collected with the OPAL detector at LEP. The branching ratio BR (b -> Bbar) x BR (Bbar -> D^0_1 l nu X) x BR (D^0_1 -> D^{*+} pi^-) is measured to be (2.64 +- 0.79 (stat) +- 0.39 (syst)) X 10^-3 for the J^P = 1^+ (D^0_1) state. For decays into the J^P = 2^+ (D^{*0}_2) state, an upper limit of 1.4 X 10^-3 is placed on the branching ratio at the 95% confidence level.

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The OPAL collaboration, G. Abbiendi. 2003-01-13. A Measurement of Semileptonic B Decays to Narrow Orbitally-Excited Charm Mesons. https://doi.org/10.1140/epjc%2Fs2003-01322-2

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