DØ W Mass

Convener: Ashutosh Kotwal

Amoung the electroweak measureables at the Tevatron, the determination of the mass of the W boson is of critical importance. Hand in hand with the determination of the mass of the top quark , and in conjunction with the precisely known mass of the Z boson , the electroweak sector of the Standard Model is confronted. Direct measurements by DØ of the masses of the W boson and the top quark place constraints on the Higgs mass .

This page contains information on the various DØ measurements of the W mass. You can find plots, publications, conference proceedings and copies of talks.

Summary of Results:

New: Improved measurement of the W mass using events in which the electron shower is close to the phi edge of one of the 32 modules in the central calorimeter. When combined with our previously published results (see below) we obtain:

MW = 80.483 +- 0.084 GeV

For details see our paper submitted to the International Europhysics Conference on High Energy Physics, July 12-18, 2001,
hep-ex/0106018 . Also see a description here .

The published DØ measurement of the W boson mass, from a combined fit to the transverse mass and lepton transverse momentum spectra, and using Run 1A+1B central calorimeter data and the Run1B end calorimeter data, is

MW = 80.482 +- 0.091 GeV

The new end calorimeter measurement is described here, and is published in:

 The previous measurement performed using the central calorimeter only is described in the following papers:

You may find more detailed information on our Run 1B central calorimeter W mass measurement here .

The current world average of the direct measurements of the W mass is:

MW = 80.394 +- 0.042 GeV [DØ, CDF, UA2, LEP2 - Summer99]

If one includes the indirect determination from NuTeV (80.250 +- 0.110 GeV) the world average
becomes 80.376 +- 0.039 GeV.

W mass summary plots
The points show direct measurements of the W boson mass by UA2, CDF, and LEP2. 
Plot of M(W) vs. M(top). 

Other W Mass Related Links: CDF , LEP2

Supplemental information

Collection of DØ W Mass Publications:

Collection of relevant conference proceedings:

Collection of relevant talks:

Collection of Publically Available DØ Internal Documents

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This page maintained by John Ellison
Last modified: Oct 7, 2001