Combination of CDF and D0 Results on W Boson Mass and Width

TL;DR

This paper combines measurements from CDF and D0 experiments to provide precise values for the W boson mass and width, including a joint analysis and standard model-based combination, refining fundamental parameters of the W boson.

Contribution

It presents a combined analysis of W boson mass and width measurements from Tevatron data, including a novel joint analysis and standard model-based width extraction.

Findings

Tevatron average W mass: 80.456 GeV

Tevatron average W width: 2.115 GeV

Combined W width: 2.135 GeV

Abstract

The results based on 1992-95 data (Run 1) from the CDF and DO 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 -> e nu) = 224 +- 13 MeV.