Quark and gluon jet properties in symmetric three jet events

Quark and gluonjets with the same energy, 24 GeV, are compared in symmetric three-jet configurations from hadronic Z decays observed by the ALEPHdetector. Jets are defined using the Durham algorithm. Gluonjets are identified using an anti-tag on b jets, based on a track impact parametermethod. The comparison of gluonand mixed flavourquark jets shows that gluonjets have a softer fragmentation function, a larger angular width and a higher particle multiplicity, Evidence is presented which shows that the corresponding differences between gluonand b jets are significantly smaller. In a statistically limited comparison the multiplicity in c jets was found to be comparable with that observed for the jets of mixed quark flavour.