Combination of CDF and D0 results on the W boson mass and width -: art. no. 092008

The results based on 1992-95 data (Run 1) from the CDF and D0 experiments on the measurements of the W boson mass and width are presented, along with the combined results. We report a Tevatron collider average M-W=80.456+/-0.059 GeV. We also report the Tevatron collider average of the directly measured W boson width Gamma(W)=2.115+/-0.105 GeV. We describe a new joint analysis of the direct W mass and width measurements. Assuming the validity of the standard model, we combine the directly measured W boson width with the width extracted from the ratio of W and Z boson leptonic partial cross sections. This combined result for the Tevatron is Gamma(W)=2.135+/-0.050 GeV. Finally, we use the measurements of the direct total W width and the leptonic branching ratio to extract the leptonic partial width Gamma(W-->enu)=224+/-13 MeV.