Z0 PARAMETERS AND Mtop FROM LEP 1990 DATA

Abstract

The four detectors ALEPH, DELPHI, L3 and OPAL have collected ≈550,000 Z0 decays during the LEP run in 1990. We have made model-independent simultaneous fits to the LEP data to determine the Z0 parameters. The mass and widths of Z0 are Mz=91.177± 0.006±0.02 (LEP) GeV , Γz=2.481±0.010 GeV , Γ had =1.734±0.010 GeV and Γ lept =83.0 ± 0.4 MeV . The number of ν families is determined to be Nν=3.01±0.05. Simultaneous fits are performed within the Standard Model framework to the LEP data and constraining the value of sin 2 θw from the [Formula: see text] colliders we get the following values for top mass, electroweak mixing angle sin 2 θw and the radiative correction [Formula: see text], sin 2 θw=0.230±0.004 and ∆r=0.056±0.011.