M. Acciarri et al., Measurement of the W-pair production cross section and W-decay branching fractions in e(+)e(-) interactions at root s=189 GeV, PHYS LETT B, 496(1-2), 2000, pp. 19-33
The data collected by the L3 experiment at LEP at a centre-of-mass energy o
f 188.6 GeV are used to measure the W-pair production cross section and the
W-boson decay branching fractions. These data correspond to an integrated
luminosity of 176.8 pb-l. The total cross section for W-pair production, co
mbining all final states, is measured to be sigma (W) = 16.24 +/- 0.37 (sta
t.) +/- 0.22 (syst.) pb. Including our data collected at lower centre-of-ma
ss energies, the hadronic branching fraction of the W-boson is determined t
o be B(W --> qq) = [68.20 +/- 0.68 (stat.) +/- 0.33 (syst.)]%. The results
agree with the Standard Model predictions. (C) 2000 Published by Elsevier S
cience B.V.