Measurement of the production rate of bb(bar) quark                            
pairs from gluons and bb(bar)bb(bar) events in hadronic Z0 decays              
  
The rate of gluons splitting to b-bbar quark pairs in hadronic Z0              
decays and the rate of final states with two b-bbar quark pairs                
are measured using data collected by OPAL.                                     
Events containing four jets are selected where two of the jets that            
are close in phase-space contain secondary decay vertices. In addition         
four jet events are selected that have secondary decay vertices in at least    
three of the four jets. Information from the event topology                    
is combined in a likelihood analysis to extract the                            
values of the gluon splitting rates.                                           
  
 Parallel session :7                   
 Plenary  session :3