Flavor tagging and the triple-gluon vertex

The triple-gluon vertex is a basic necessity for QCD to be asymptotically free; however, a direct experimental test is still lacking. We have found a simple method to test the triple-gluon vertex. This method uses flavor tagging in four-jet events in electron-positron annihilation at the Z0 resonance, which is capable of strictly distinguishing the Abelian model and QCD and is essentially unaffected by fragmentation.