Charged Multiplicity of Hadronic Events Containing Heavy-Quark Jets

The charged-particle multiplicities of hadronic events deriving from produced bottom or charm quarks have been measured in the Mark II detector at PEP in $e^{+}{e}^{-}$ annihilation at 29 GeV. For events containing one semileptonic and one hadronic weak decay, we find multiplicities of 15.2±0.5±0.7 for bottom and 13.0±0.5±0.8 for charm. The corresponding multiplicities of charged particles accompanying the pair of heavy hadrons are 5.2±0.5±0.9 for bottom, and 8.1±0.5±0.9 for charm.