Final R-value results from 2–5 GeV from BES and QCD test with R scan data
نویسندگان
چکیده
منابع مشابه
BES R measurements and J/ψ decays
A precision measurement of R will reduce the uncertainty on α(Mz), narrow the predicted mass window of Higgs boson mH and reduce the uncertainty on the anomalous magnetic moment of muon aμ. R has been measured in the energy region from hadron production threshold to Z pole. Previous R measurements below 5 Gev were carried out almost 20 years ago and the largest uncertainty on R comes from the m...
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The values of R = σ(ee → hadrons)/σ(ee → μμ) for 85 center-of-mass energies between 2 and 5 GeV are reported. Preliminary results using partial wave analysis for J/ψ decays to γππ, γKK, φππ and φKK are presented. The BESIII/BEPCII, a project for the future of BES, is introduced. 1 PRESENT STATUS OF BESII/BEPC The Beijing Spectrometer (BES) at Beijing Electron Positron Collider (BEPC), so far th...
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ژورنال
عنوان ژورنال: Nuclear Physics B - Proceedings Supplements
سال: 2003
ISSN: 0920-5632
DOI: 10.1016/s0920-5632(03)90514-7