Journal article
Update of electroweak parameters from Z decays
D Buskulic, D Decamp, C Goy, JP Lees, MN Minard, B Mours, B Pietrzyk, R Alemany, F Ariztizabal, P Comas, JM Crespo, M Delfino, E Fernandez, M Fernandez-Bosman, V Gaitan, L Garrido, T Mattison, A Pacheco, C Padilla, A Pascual Show all
Zeitschrift Fur Physik C Particles and Fields | SPRINGER VERLAG | Published : 1993
DOI: 10.1007/BF01650432
Abstract
Based on 520 000 fermion pairs accumulated during the first three years of data collection by the ALEPH detector at LEP, updated values of the resonance parameters of the Z are determined to be MZ=(91.187±0.009) GeV, ΓZ=(2.501±0.012) GeV, σhad 0=(41.60±0.27) nb, and Rℓ=20.78±0.13. The corresponding number of light neutrino species is Nν=2.97±0.05. The forward-backward asymmetry in lepton-pair decays is used to determine the ratio of vector to axial-vector couplings of leptons:gV 2(MZ 2)/gA 2(MZ 2)=0.0052±0.0016. Combining this with ALEPH measurements of the b and c quark asymmetries and τ polarization gives sin2θW eff=0.2326±0.0013. Assuming the minimal Standard Model, and including measure..
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