A search for single top quark production via flavour changing neutral curre
nts (FCNC) was performed with data collected by the OPAL detector at the e(
+)e(-) collider LEP. Approximately 600 pb(-1) of data collected at roots =
189-209 GeV were used to search for the FCNC process e(+)e(-) --> tc(u) -->
bWc(u). This analysis is sensitive to the leptonic and the hadronic decay
modes of the W boson. No evidence for a FCNC process is observed. Upper lim
its at the 95% confidence level on the single top production cross-section
as a function of the centre-of-mass energy are derived. Limits on the anoma
lous coupling parameters K-gamma and K-Z are determined from these results.
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