HADRON PRODUCTION IN e + e - ANNIHILATION FROM , / i = 5 . 0 TO 7 . 4 GeV
نویسندگان
چکیده
The total cross section for e+e-annihilation into hadrons has been measured * by the Crystal Ball collaboration at the SLAC storage ring SPEAR, for center-of-mass energies 4 from 5.0 to 7.4 GeV. The data show no evidence for new thresholds or resonant structure in this energy range. The average value of R, the radiatively corrected total hadronic cross section divided by the point p-pair cross section, is 3.44 f 0.03 f 0.18. Fitting the order-cr,2 QCD prediction for R to the Crystal Ball data yields a value for the strong interaction coupling constant of (Y, = 0.12 f 0.11 at fi = 6.0 GeV. The tot al cross section for e+e-annihilation into hadrons has been measured by the Crystal Ball collaboration at the SLAC storage ring SPEAR, for center-of-mass energies fi from 5.0 to 7.4 GeV. The data show no evidence for new thresholds or resonant structure in this energy range. The average value of R, the radiatively corrected total hadronic cross section divided by the point p-pair cross section, is 3.44 f 0.03 f 0.18. Fitting the order-as2 QCD prediction for R to the Crystal Ball data yields a value for the strong interaction coupling constant of a, = 0.12 f 0.11 at fi = 6.0 GeV.
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