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Open AccessJournal ArticleDOI

Measurements of the cross section for e(+)e(-) --> hadrons at center-of-mass energies from 2 to 5 GeV.

J. Z. Bai, +185 more
- 11 Mar 2002 - 
- Vol. 88, Iss: 10, pp 101802
TLDR
Values of R = sigma(e(+e(-)-->hadrons)/sigma( e(+)e (-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider are reported.
Abstract
We report values of $R\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{\sigma}({e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathrm{hadrons})/\ensuremath{\sigma}({e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})$ for 85 center-of-mass energies between 2 and $5\mathrm{GeV}$ measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

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Journal ArticleDOI

Precision electroweak measurements on the Z resonance

TL;DR: In this paper, the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP are reported.
Journal ArticleDOI

Heavy quarkonium: progress, puzzles, and opportunities

Nora Brambilla, +69 more
TL;DR: The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress as mentioned in this paper.
Journal ArticleDOI

Generalized parton distributions

Markus Diehl
- 01 Dec 2003 - 
TL;DR: In this article, the authors give an overview of the theory for generalized parton distributions and their role in small-x physics, and present strategies for phenomenological analysis, including the use of these quantities for describing soft contributions to exclusive processes at large energy and momentum transfer.
Journal ArticleDOI

The anomalous magnetic moment of the muon in the Standard Model

T. Aoyama, +149 more
- 03 Dec 2020 - 
TL;DR: The current status of the Standard Model calculation of the anomalous magnetic moment of the muon is reviewed in this paper, where the authors present a detailed account of recent efforts to improve the calculation of these two contributions with either a data-driven, dispersive approach, or a first-principle, lattice approach.
Journal ArticleDOI

Reevaluation of the hadronic contributions to the muon g−2 and to \alpha (M^{2}_{Z})

TL;DR: In this paper, the authors reevaluate the hadronic contributions to the muon magnetic anomaly, and to the running of the electromagnetic coupling constant at the Z-boson mass, and find that the reduced electromagnetic coupling strength at M ✓ Z ≥ 2 leads to an increase by 12 ǫ in the central value of the Higgs boson mass obtained by the standard Gfitter fit to electroweak precision data.
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Posted Content

Few body states in Lund string fragmentation model

TL;DR: In this paper, the authors developed the formalism to use the basic Lund Model area law directly for Monte Carlo simulations, in particular at the few GeV level in e^+e^- annihilation as in BEPC.
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