par Abreu, Pedro;Bertrand, Daniel 
;Bricman, Claude ;Vander Velde, Catherine ;Wickens, John H. ; [et al.]
Référence Physics letters. Section B, 255, 3, page (466-476)
Publication Publié, 1991
;Bricman, Claude ;Vander Velde, Catherine ;Wickens, John H. ; [et al.]Référence Physics letters. Section B, 255, 3, page (466-476)
Publication Publié, 1991
Article révisé par les pairs
| Résumé : | In four-jet events from e+e-→Z0→multihadrons one can separate the three principal contributions from the triple-gluon vertex, double gluon-bremsstrahlung and the secondary quark-antiquark production, using the shape of the two-dimensional angular distributions in the generalized Nachtmann-Reiter angle 0NR* and the opening angle of the secondary jets. Thus one can identify directly the contribution from the triple-gluon vertex without comparison with a specific non-QCD model. Applying this new method to events taken with the DELPHI-detector we get for the ratio of the colour factor NC to the fermionic Casimir operator CF: NC/C F=2.55±0.55(stat.)±0.4(fragm.+models)±0.2(error in bias) in agreement with the value 2.25 expected in QCD from NC=3 and CF=4/3. |
