Charged particle multiplicity in e(+)e(-)-> q(q)over-bar events at 161 and 172 GeV and from the decay of the W boson

The data collected by DELPHI in 1996 have been used to measure the average charged particle multiplicities and dispersions in qq̄ events at centre-of-mass energies of √s = 161 GeV and √s = 172 GeV, and the average charge multiplicity in WW events at √s = 172 GeV. The multiplicities in qq̄ events are...

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Bibliografiska uppgifter
Huvudupphovsmän: Abreu, P, Adam, W, Adye, T, Ajinenko, I, Alekseev, G, Alemany, R, Allport, P, Almehed, S, Amaldi, U, Amato, S, Andersson, P, Andreazza, A, Antilogus, P, Apel, W, Arnoud, Y, Asman, B, Augustin, J, Augustinus, A, Baillon, P, Bambade, P, Barao, F, Barbi, M, Bardin, D, Barker, G, Baroncelli, A
Materialtyp: Journal article
Språk:English
Publicerad: 1998
Beskrivning
Sammanfattning:The data collected by DELPHI in 1996 have been used to measure the average charged particle multiplicities and dispersions in qq̄ events at centre-of-mass energies of √s = 161 GeV and √s = 172 GeV, and the average charge multiplicity in WW events at √s = 172 GeV. The multiplicities in qq̄ 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. © 1998 Elsevier Science B.V.