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A measurement of the branching fractions of the b-quark into charged and neutral b-hadrons

The DELPHI Collaboration·J. Abdallah
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Abstract

The production fractions of charged and neutral b-hadrons in b-quark events from Z0 decays have been measured with the DELPHI detector at LEP. An algorithm has been developed, based on a neural network, to estimate the charge of the weakly-decaying b-hadron by distinguishing its decay products from particles produced at the primary vertex. From the data taken in the years 1994 and 1995, the fraction of bbar-quarks fragmenting into positively charged weakly-decaying b-hadrons has been measured to be: f^+ = (42.09 +/- 0.82 (stat.) +/- 0.89 (syst.))%. Subtracting the rates for charged Xibar_b^+ and Omegabar_b^+ baryons gives the production fraction of B^+ mesons: f_Bu = (40.99 +/- 0.82 (stat.) +/- 1.11 (syst.))%.

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The DELPHI Collaboration, J. Abdallah. 2003-11-03. A measurement of the branching fractions of the b-quark into charged and neutral b-hadrons. https://doi.org/10.1016/j.physletb.2003.09.070

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