A study of four-fermion final states with high multiplicity at LEP

G Alexander; J Allison; N Altekamp; K Ametewee; KJ Anderson; S Anderson; S Arcelli; S Asai; D Axen; G Azuelos; AH Ball; E Barberio; RJ Barlow; R Bartoldus; JR Batley; G Beaudoin; J Bechtluft; C Beeston; T Behnke; AN Bell; KW Bell; G Bella; S Bentvelsen; P Berlich; S Bethke; O Biebel; V Blobel; IJ Bloodworth; JE Bloomer; P Bock; HM Bosch; M Boutemeur; BT Bouwens; S Braibant; RM Brown; HJ Burckhart; C Burgard; R Bürgin; P Capiluppi; RK Carnegie; AA Carter; JR Carter; CY Chang; C Charlesworth; DG Charlton; D Chrisman; SL Chu; PEL Clarke; I Cohen; JE Conboy; OC Cooke; M Cuffiani; S Dado; C Dallapiccola; GM Dallavalle; C Darling; S de Jong; LA del Pozo; MS Dixit; E do Couto e Silva; M Doucet; E Duchovni; G Duckeck; IP Duerdoth; JEG Edwards; PG Estabrooks; HG Evans; M Evans; F Fabbri; P Fath; F Fiedler; M Fierro; HM Fischer; R Folman; DG Fong; M Foucher; H Fukui; A Fürtjes; P Gagnon; A Gaidot; JW Gery; J Gascon; SM Gascon-Shotkin; NI Geddes; C Geich-Gimbel; SW Gensler; FX Gentit; T Geralis; G Giacomelli; P Giacomelli; R Giacomelli; V Gibson; WR Gibson; DM Gingrich; J Goldberg; MJ Goodrick; W Gorn; C Grandi; E Gross; M Gruwé

Journal article

A study of four-fermion final states with high multiplicity at LEP

G Alexander, J Allison, N Altekamp, K Ametewee, KJ Anderson, S Anderson, S Arcelli, S Asai, D Axen, G Azuelos, AH Ball, E Barberio, RJ Barlow, R Bartoldus, JR Batley, G Beaudoin, J Bechtluft, C Beeston, T Behnke, AN Bell Show all

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics | ELSEVIER SCIENCE BV | Published : 1996

DOI: 10.1016/0370-2693(96)00397-8

Abstract

A search for ℓ+ℓ- qq̄ (ℓ = e, μ) four-fermion final states in high multiplicity events has been performed at √s ≈ mz and above the Z peak at √s = 130 GeV and √s = 136 GeV. The data taken with OPAL correspond to an integrated luminosity of 132.4 pb-1 and 5.3 pb-1 at √s ≈ mz and √s = 130-136 GeV, respectively. While at the Z resonance the data are in good agreement with the Standard Model predictions, we find more events than expected at √s - 130-136 GeV, especially in the μ+μ- qq̄ channel, where 5 events remain after all cuts, with only 0.6 predicted by the Monte Carlo simulation. For all center-of-mass energies the observed shapes of the differential distributions are consistent with the pre..

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