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Final R-value results from 2-5 GeV from BES and QCD test with R scan data

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 نشر من قبل Zhengguo Zhao
 تاريخ النشر 2002
  مجال البحث
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Final results of the measurement of $R = sigma(e^+e^- to hadrons) /sigma(e^+e^- to mu^+mu^-)$ in the energy region from 2 to 5 GeV with the upgraded Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC) are presented. Preliminary results of the inclusive momentum spectra and second binomial moment measured with the $R$ scan data at 2.2, 2.6, 3.0, 3.2, 4.6 and 4.8 GeV are reported.



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