Combination of CDF and D0 results on the W boson mass and width
  The results on the direct measurements of the W-boson mass and width, based on the data collected by the Tevatron experiments CDF and D0 at Fermilab are summarised and combined. The CDF Run-0 (1988-1889) and Run-I (1992-1995) results have been re-averaged using the BLUE method and combined with Run-I D0 results and the latest published results from CDF taken from the first period of Run-II (2001-2004). The results are corrected to have consistency between the parton distribution functions and electroweak parameters. The resulting Tevatron averages for the mass and total decay width of the W boson are: Mw = 80432 +/- 39 MeV and Gamma_W = 2056 +/- 62 MeV. The inclusion of a preliminary Run-II measurement of Gamma_W from D0 gives Gamma_W = 2050 +/- 58 MeV. 
Tevatron Electroweak Working Group