Measurement of the B hadron energy distribution in Z0 decays

We have measured the B hadron energy distribution in Z0 decays using a sample of semileptonic B decays recorded in the SLD experiment at SLAC. The energy of each tagged B hadron was reconstructed using information from the lepton and a partially reconstructed charm-decay vertex. We compared the scaled energy distribution with several models of heavy quark fragmentation. The average scaled energy of primary B hadrons was found to be 〈xEB〉=0.716±0.011(stat)-0.022+0.021(syst).