TY - JOUR

T1 - Precision Electroweak Measurements on the Z resonance.

AU - Jones, Roger W. L.

AU - Borissov, Guennadi

AU - Grunewald, M. W.

AU - Ratoff, Peter N.

AU - Smizanska, Maria

N1 - This paper summarizes the LEP I electroweak measurements that both test the theory and allow prediction of a wide range of processes. Jones worked on the heavy flavour and inclusive charge asymmetry combinations and chapters, and was chief editor for the inclusive charge asymmetry chapter. 154 citations (SPIRES). RAE_import_type : Journal article RAE_uoa_type : Physics

PY - 2006/3/1

Y1 - 2006/3/1

N2 - We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron–positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLD experiment using a polarised beam at SLC. The measurements include cross-sections, forward–backward asymmetries and polarised asymmetries. The mass and width of the Z boson, mZ and ΓZ, and its couplings to fermions, for example the ρ parameter and the effective electroweak mixing angle for leptons, are precisely measured: The number of light neutrino species is determined to be 2.9840±0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward–backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, , and the mass of the W boson, . These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of mt and mW, the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than at 95% confidence level.

AB - We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron–positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLD experiment using a polarised beam at SLC. The measurements include cross-sections, forward–backward asymmetries and polarised asymmetries. The mass and width of the Z boson, mZ and ΓZ, and its couplings to fermions, for example the ρ parameter and the effective electroweak mixing angle for leptons, are precisely measured: The number of light neutrino species is determined to be 2.9840±0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward–backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, , and the mass of the W boson, . These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of mt and mW, the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than at 95% confidence level.

KW - Electron–positron physics

KW - Electroweak interactions

KW - Decays of heavy intermediate gauge bosons

KW - Fermion–antifermion production

KW - Precision measurements at the Z resonance

KW - Tests of the Standard Model

KW - Radiative corrections

KW - Effective coupling constants

KW - Neutral weak current

KW - Z boson

KW - W boson

KW - Top quark

KW - Higgs boson

U2 - 10.1016/j.physrep.2005.12.006

DO - 10.1016/j.physrep.2005.12.006

M3 - Journal article

VL - 427

SP - 257

EP - 454

JO - Physics Reports

JF - Physics Reports

IS - 5-6

ER -