Four candidates for charmless hadronic B decay are observed in a data sample of four million hadronic Z decays recorded by the ALEPH detector at LEP. The probability that these events come from background sources is estimated to be less than 10-6. The average branching ratio of weakly decaying B hadrons (a mixture of B0d, B0s and Λb weighted by their production cross sections and lifetimes, here denoted B) into two long-lived charged hadrons (pions, kaons or protons) is measured to beBr (B -> h+h-) = (1.7+1.0-0.7 +/- 0.2) × 10-5. The relative branching fraction Br(B0d(s) -> π+π- (K-))/(Br(B0d(s) -> h+h-)) is measured to be 1.0+0.0 +0.0-0.3 -0.1. In addition, branching ratio upper limits are obtained for a variety of exclusive charmless hadronic two-body decays of B hadrons.
Observation of charmless hadronic B decays
GREGORIO, ANNA;BOSISIO, LUCIANO;GIANNINI, GIANROSSANO;
1996-01-01
Abstract
Four candidates for charmless hadronic B decay are observed in a data sample of four million hadronic Z decays recorded by the ALEPH detector at LEP. The probability that these events come from background sources is estimated to be less than 10-6. The average branching ratio of weakly decaying B hadrons (a mixture of B0d, B0s and Λb weighted by their production cross sections and lifetimes, here denoted B) into two long-lived charged hadrons (pions, kaons or protons) is measured to beBr (B -> h+h-) = (1.7+1.0-0.7 +/- 0.2) × 10-5. The relative branching fraction Br(B0d(s) -> π+π- (K-))/(Br(B0d(s) -> h+h-)) is measured to be 1.0+0.0 +0.0-0.3 -0.1. In addition, branching ratio upper limits are obtained for a variety of exclusive charmless hadronic two-body decays of B hadrons.Pubblicazioni consigliate
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