Measurement of the Production Rate of Charm Quark                              
Pairs from Gluons in Hadronic Z0 Decays                                        
  
The rate of secondary charm-quark pair production has been measured            
in 4.4 million hadronic Z0 decays collected by OPAL. By selecting              
events with three jets and tagging charmed hadrons in the gluon jet            
candidate using leptons and D* mesons, the average number of secondary         
charm-quark pairs per hadronic event is found to be                            
(3.20+/-0.21+/-0.38) x 10^-2.                                                  
  
 Parallel session :7                   
 Plenary  session :3