Combined preliminary results on the mass and width of the W boson measured by the LEP experiments

The combinations of the preliminary W mass and width measurements of the LEP experiments are presented. Measurements of the W mass obtained from data corresponding to a total integrated luminosity of approximately 2500 pb-1 are combined to give: m_W = 80.447 +- 0.042 GeV. This result includes the LEP W mass determination from the threshold cross section measurement. The systematic uncertainities associated with final state interactions are, for the first time, determinated utilising direct measurements of these processes. The separate results from the W+W- -> qqbarlnubar_l and W+W- -> qqbarqqbar decay channels are consistent, with a difference in the masses obtained from the two channels of Deltam_W(qqbarqqbar-qqbarlnubar_l) = +9 +- 44 MeV. A direct measurement of the width of the W boson gives: Lambda_W = 2.150 +- 0.0091 GeV. These results include all LEP published and preliminary measurements which were available in July 2002.