Title: Inclusive Sigma+ and Sigma0 Production in Hadronic Z decays


 We report on measurements of the inclusive production rate of
 Sigma+ and Sigma0 baryons in hadronic Z decays collected with
 the L3 detector at LEP. The Sigma+ baryons are detected through the decay
 Sigma+ -> p pi0, while the Sigma0 baryons are detected via the decay 
 mode Sigma0 -> Lambda gamma. The average numbers of Sigma+ and Sigma0
 per hadronic Z decay are measured to be:
 < N_{Sigma+}> + < N_{\bar{Sigma}+}>  = 0.114+- 0.011(stat)+- 0.009(syst) 
 < N_{Sigma0}> + < N_{\bar{Sigma}0}>  = 0.095+- 0.015(stat)+- 0.013(syst)
 These rates are found to be higher than the predictions from Monte Carlo 
 hadronization models and analytical parameterizations of strange baryon
 production.

parallel session #PA 1,2
plenary session #Pl 12 ?

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* paper 203 * Phys.Lett.B465 (1999) 323-334
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