Related papers: Reconstruction and approximation effects on W mass…
One of the most powerful methods for obtaining a precision measurement of M_W at LEP2 is from direct reconstruction of the invariant mass distribution of W bosons produced in e+e- --> W+W-. We investigate the effects on the W line shape,…
Two measurements are presented of estimators sensitive to the Colour Reconnection effect in WW events at LEP2. The results are compared with various phenomenological Monte Carlo implementations of the effect. A feasibility study is…
I discuss a few issues related to the systematic error on the top mass measurement at hadron colliders, due to hadronization effects. Special care is taken about the impact of bottom-quark fragmentation in top decays, especially on the…
The W Mass and QCD Working Group discussed a wide variety of topics relating to present and future measurements of M(W) at LEP2, including QCD backgrounds to W+W- production. Particular attention was focused on experimental issues…
Studying the properties of the W boson plays a key role in precision tests of the Standard Model. The key measurements performed over the last decade will be reviewed. W-pair and single-W cross-sections and W decay branching fractions are…
The measurement of the mass of the W boson, m_W, by direct reconstruction is described. The combination of all measurements of the four LEP experiments yields m_W = 80.412 +- 0.042 GeV. Together with several other measurements the extracted…
At LEP II it is hoped to measure the W mass to an accuracy of around 40 MeV. This will require direct reconstruction of the mass of the W from its decay products in both the semi-leptonic and hadronic decay channels. Final state…
After the first observations of W bosons in leptonic interactions, about 4000 WW candidate events per experiment have been collected at LEP2. This data allows the measurement of the WW production cross section at different centre-of-mass…
Measurements of hadronic final state interactions in W-pair events at LEP are presented. In particular, different scenarios of colour reconnection are studied. The data agree with moderate colour reconnection effects. Extreme scenarios are…
Previous studies of the QED systematic uncertainties on the LEP measurement of the W-boson mass have used idealized event selections and fitting procedures. In this paper, the Monte Carlo tandem of KoralW and YFSWW is used to investigate…
Recent LEP results on electroweak precision measurements are reviewed. Line-shape and asymmetries analysis on the Z peak is described. Then, the consistency of the Standard Model predictions with experimental data and consequent limits on…
We analyze different prescriptions for the inclusion of target mass effects in the extraction of parton distributions from the measured structure functions. As a main result, the problem of defining parton distributions in the presence of…
The mass of the W boson has been measured by the LEP collaborations from the data recorded during the LEP2 programme at e+ e- centre of mass energies from 161 to 209 GeV, giving the result : mw = 80.450 +/- 0.039 GeV/c^2. This paper…
We review the precision measurement of the mass of the W-boson at LEP. We discuss the techniques used by the four LEP experiments to determine the mass of the W-boson as well as the major sources of systematic uncertainty. The measurement…
An alternative W mass estimator in e+e- -> WW -> qqqq events at LEP2 is designed to optimize the balance between the statistical uncertainty and the systematic uncertainty due to a possible Colour Reconnection effect. The preliminary result…
An often-cited fact regarding mixing or mixture distributions is that their density functions are able to approximate the density function of any unknown distribution to arbitrary degrees of accuracy, provided that the mixing or mixture…
Precise measurements of the mass and width of the W boson are carried out in e+e- collisions at LEP, by kinematic reconstruction of the invariant mass distributions of WW->qqlv and WW->qqqq candidate events. The most recent combination of…
The use of an unfolding procedure is proposed as an alternative method of extracting the $W$ boson mass from the data measured at LEP2, which may improve the accuracy of this measurement. The benefits of the direct unfolding method based on…
The analyses and results on WW physics obtained in the first year of running of LEP2 are summarized. The determination of the W mass, both through the measurement of the WW production cross section at a center-of-mass energy of 161 GeV and…
The W-mass measurements from LEP and the results of a global fit of the Standard Model parameters to the electroweak data are presented. Comprehensive studies of experimental systematic effects allowed a measurement of the W mass with an…