Lineshape Results from Lep - 1993
نویسنده
چکیده
In 1993 LEP performed a scan at three energy points around the Z 0 mass, with the primary aim of substantially improving the errors on M Z and ? z. The results of the preliminary lineshape analyses of the 4 LEP experiments are presented here, together with the combined LEP averages. The Z 0 mass and width are determined as M Z = 91:1899 0:0017 exp 0:004 lep Gev and ? z = 2:4971 0:0027 exp 0:0027 lep Gev. Improvements in R had and had pole , and a Standard Model t for m t are also presented. Finally the data are analysed in terms of R inv and 3 which do not depend strongly on m t and m H. These show no evidence for any signiicant deviations.
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