European Organization for Nuclear Research

Abstract

The production fractions of charged and neutral b-hadrons in b-quark events from Z 0 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 b-quarks fragmenting into positively charged weakly-decaying b-hadrons has been measured to be:42.09 ± 0.82(stat.) ± 0.89(syst.))%. Subtracting the rates for charged Ξ + b and Ω + b baryons gives the production fraction of B + mesons:f Bu = (40.99 ± 0.82(stat.) ± 1.11(syst.))%.