The production of W+W- pairs is analysed in a data sample collected by ALEP
H at a mean centre-of-mass energy of 182.7 GeV, corresponding to an integra
ted luminosity of 57 pb(-1). Cross sections are given for different topolog
ies of W decays into leptons or hadrons. Under Standard Model assumptions f
or the W-pair production and decay, the W-pair cross section is measured to
be 15.57 +/- 0.62 (stat.) +/- 0.29 (syst.) ph. Using also the W-pair data
samples collected by ALEPH at lower centre-of-mass energies, the decay bran
ching ratio of the W boson into hadrons is measured to be B(W --> hadrons)
= 68.93 +/- 1.21 (stat.) +/- 0.51 (syst.)%, allowing a determination of the
CKM matrix element /V-cs/ = 1.043 +/- 0.058 (stat.) +/- 0.026 (syst.). The
agreement of the cross sections with the Standard Model prediction allows
a limit to be set on the W decay rate to undetectable final states. (C) 199
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