相关论文: WW Physics at LEP2
The mass and width of the W boson are measured using e+e- -> W+W- events from the data sample collected by the OPAL experiment at LEP at centre-of-mass energies between 170 GeV and 209 GeV. The mass (mw) and width (gw) are determined using…
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…
From 1996 up to 2000 the LEP collider at CERN has operated at center of mass energies above the production threshold for W boson pairs of approximately 160 GeV. The obtained data are used to extract a preliminary W mass value of (80.450 +-…
The mass of the W boson is measured at LEP by fully reconstructing the W boson decays. The measurement techniques and systematic uncertainties are presented. The current measurement of the mass of the W boson at LEP yields 80.412 +/- 0.042…
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…
In 1996, after another set of upgrades, LEP began running for the first time at center-of-mass energies above the W-pair production threshold. This new energy regime is rich in physics and offers new tests of the Standard Model, increased…
The CDF and D0 collaborations have analyzed up to ~200/pb of Run 2 physics data to measure W production properties such as the W cross section, the W width, lepton universality and the W charge asymmetry. From the cross section…
A summary of the W-boson properties measured by the four LEP collaborations is presented here. These properties are updated to take into account the most recent results presented at the ICHEP98 conference.
The Run II physics program of CDF is proceeding with approximately 200 pb-1 of analysis quality data collected at the center-of-mass energy of 1.96 TeV. The Electroweak measurements are among the first and most important benchmarks towards…
Recent studies to finalize the systematic error estimates on the measurement of the mass of the W boson at LEP2 are reviewed. Results including a new preliminary value from Aleph are updated together with the world average which is now…
Radiative returns to the Z resonance (Zgamma events) are used to determine the LEP2 centre-of-mass energy from the data collected with the ALEPH detector in 1997. The average centre-of-mass energy is measured to be: E_CM = 182.50 +-…
From a total data sample of 701.1 pb^-1 recorded with e+e- centre-of-mass energies of sqrt = 161-209 GeV with the OPAL detector at LEP, 11693 W-pair candidate events are selected. These data are used to obtain measurements of the W-pair…
The measurements of four-fermion production rates performed at LEP2 in e+e- collisions at centre-of-mass energies ranging from 161 to 209 GeV are presented. The focus is put on processes that involve the production and decay of W or Z…
The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the…
How massive elementary particles get their mass is one of the greatest open questions in physics. Two of the major goals of the current LEP2 physics program that help to address this question are (a) to measure as precisely as possible the…
In the first part of this report, we discuss the prospects for measuring the W mass and width in Run II. The basic techniques used to measure M_W are described and the statistical, theoretical and detector-related uncertainties are…
From a data sample of 183 pb^-1 recorded at a center-of-mass energy of roots = 189 GeV with the OPAL detector at LEP, 3068 W-pair candidate events are selected. Assuming Standard Model W boson decay branching fractions, the W-pair…
The W-boson mass has been measured using the ALEPH detector at LEP. Preliminary results from data taken in 1998 are added to previous measurements to give mW = 80.411 +- 0.064(stat.) +- 0.037(syst.) +- 0.022(BE-CR) +- 0.018(LEP) GeV/c2.
Previous studies of the physics potential of LEP2 indicated that with the design luminosity of 500 inverse picobarn one may get a direct measurement of the mass of the W-boson with a precision in the range 30 - 50 MeV. This report presents…
The properties of the W boson are reviewed. Particular emphasis is placed on recent measurements from the LEP2 and Tevatron experiments.