Reevaluation of the Hadronic Contribution to $\alpha (M_Z^2)$

Abstract

We reevaluate the hadronic part of the electromagnetic vacuum expectation value using the standard dispersion integral approach that utilizes the hadronic cross section measured in $\ee$ experiments as input. Previous analyses are based upon point-by-point trapezoidal integration which does not treat experimental errors in an optimal way. We use a technique that weights the experimental inputs by their stated uncertainties, includes correlations, and incorporates some refinements. We find the five-flavor hadronic contribution to the fractional change in the electromagnetic coupling constant at $q^2=M_Z^2$, $\Delta \alpha (MZ)$, to be $0.02752\pm 0.00046$, which leads to a value of the electromagnetic coupling constant, ${\alpha }^{-1}(M_Z^2)=128.96\pm 0.06$. [This is an updated version of SLAC-PUB-6710 (hep-ph/9411353) which fixes a small bias in the fitting procedure (1/3 of the change) and incorporates a new and precise cross section measurement near charm threshold (2/3 of the change).]

46 pages, PHYZZX document with 8 tar-ed, gzipped, uuencoded encapsulated postscript figures. Uncompressed postscript file (2.01 Mb) available to DECNET users as SLC::USER_DISK_SLC1:[MORRIS]alphamz8.ps

References in corpus (3)

• Hadronic contributions to $(g-2)$ of the leptons and to the effective fine structure constant $\alpha (M_Z^2)$
• A determination of the QED coupling at the $Z$ pole
• $R_{had}$ at the $B$-factory

Cited by in corpus (37)

• Generalized Parton Distributions
• Precision Electroweak Measurements on the Z Resonance
• Electroweak Measurements in Electron-Positron Collisions at W-Boson-Pair Energies at LEP
• Physics with the KLOE-2 experiment at the upgraded DA$\varphi$NE
• New Results on the Hadronic Contributions to alpha(M_Z) and to (g-2)_mu
• Predictions for g-2 of the muon and alpha_QED(M_Z^2)
• Measurement of the Total Cross Section for Hadronic Production by e+e- Annihilation at Energies between 2.6-5 Gev
• Improved Determination of $\alpha (M_{\mathrm{Z}}^2$) and the Anomalous Magnetic Moment of the Muon
• Improved Determination of alpha_QED(M_Z^2) and the Anomalous Magnetic Moment of the Muon
• The SM prediction of g-2 of the muon
• A theory driven analysis of the effective QED coupling at $M_Z$
• Calculation of the QED Coupling alpha (M_Z) in the Modified Minimal-Subtraction Scheme
• Results and Techniques of Multi-Loop Calculations
• A light complex scalar for the electron and muon anomalous magnetic moments
• Resolving electron and muon $g-2$ within the 2HDM
• Supersymmetry versus precision experiments revisited
• Two-loop heavy top corrections to the Z boson partial widths
• Limits on Non-Commuting Extended Technicolor
• Logarithmic expansion of electroweak corrections to four-fermion processes in the TeV region
• QCD Sum Rule Determination of $\alpha (M_Z)$ with Minimal Data Input
• A new determination of the QED coupling alpha(M_Z^2) lets the Higgs off the hook
• Precision Physics at LEP
• Probability and Measurement Uncertainty in Physics - a Bayesian Primer
• Measurement of the Running of the Fine-Structure Constant
• Determination of the Mass of the W Boson Using the D0 Detector at the Tevatron
• Electroweak effects in the $B^0-{\bar{B}}^0$ mixing
• Prospects for e+e- physics at Frascati between the phi and the psi
• Neutrino masses and magnetic moments of electron and muon in the Zee Model
• Measurement of the Inclusive Charm Cross Section at 4.03 GeV and 4.14 GeV
• Experimental Precision Tests for the Electroweak Standard Model
• Testing QCD with Hypothetical Tau Leptons
• Precision W-boson and top-quark mass determinations at a muon collider
• Calculation of gluon and four-quark condensates from the operator expansion
• Where is the Higgs?
• R-values in Low Energy e^+e^- Annihilation
• Formulation of relativistic dissipative fluid dynamics and its applications in heavy-ion collisions
• Electroweak interactions: a theoretical overview