Determination of the Production Rate of D^*0 Mesons and of the Ratio V/(V+P) in Z^0 -> cc(bar) Decays

Abstract

In e^+e^- collisions at centre-of-mass energies around 91 GeV, D^*0 mesons have been reconstructed using data collected with the OPAL detector at LEP. The hadronisation fraction has been measured to be f(c -> D^*0) = 0.218 +/- 0.054 +/- 0.045 +/- 0.007, where the errors correspond to the statistical and systematic errors specific to this analysis, and to systematic uncertainties from externally measured branching fractions, respectively. Together with previous OPAL measurements of the hadronisation fractions of other charmed mesons, this value is used to investigate the relative production of observed vector and pseudoscalar charmed mesons in Z^0 -> cc(bar) decays. The production ratio is determined to be P^eff_V = V/(V+P) = 0.57 +/- 0.05. The relative primary production of vector and pseudoscalar mesons, P^prim_V, is studied in the context of the production and decay of orbitally excited charmed resonances. The first measurement of the inclusive D^*+_s production rate in hadronic Z^0 decays is presented.