W Mass and Properties
  Precise measurements of the mass and width of the W boson are sensitive to radiative corrections and can be used to place limits on new physics beyond the Standard Model and validate the consistency of the model. In particular, the W boson mass constrains the mass of the, as yet unobserved, Higgs boson and the width can be used to place limits on the existence of new particles that couple to the W. Results are presented from proton anti-proton collisions recorded by the CDF and D0 experiments at the Fermilab Tevatron collider, operating at a centre of mass energy of 1.96 TeV. The uncertainty on the W mass is determined to be 76 MeV by CDF and the width, by D0, to be 2011 +/- 90 (stat.) +/- 107 (syst.) MeV. 
Mark Lancaster (on behalf of the CDF and DO collaborations)