The data collected by DELPHI in 1996 have been used to measure the average charged particle multiplicities and dispersions in View the MathML source events at centre-of-mass energies of View the MathML source GeV and View the MathML source GeV, and the average charge multiplicity in WW events at View the MathML source GeV. The multiplicities in View the MathML source events are consistent with the evolution predicted by QCD. The dispersions in the multiplicity distributions are consistent with Koba-Nielsen-Olesen (KNO) scaling. The average multiplicity of charged particles in hadronic W decays has been measured for the first time; its value, 19.23±0.74(stat+syst), is consistent with that expected for an e+e− interaction at a centre-of-mass energy equal to the W mass. The charged particle multiplicity in W decays shows no evidence of effects of colour reconnection between partons from different W's at the present level of statistics.
Abreu, P. ; Cortina Gil, Eduardo ; DELPHI Collaboration ; et. al. Charged particle multiplicity in e+ e- ---> q anti-q events at 161-GeV and 172-GeV and from the decay of the W boson. In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics, Vol. 416, no.1-2, p. 233–246 (1998)