Search for single top quark production at LEP2

A search for single top quark production via flavour changing neutral currents (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 limits 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 anomalous coupling parameters K-gamma and K-Z are determined from these results. (C) 2001 Elsevier Science B.V. All rights reserved.