e+e− physics with the PLUTO detector

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“…The BES collaboration has also performed the analysis including only events with greater than two charged tracks; although the statistics are smaller, the results obtained agree well with the results shown here. The R values for E cm below 4 GeV are in good agreement with results from γγ2 [7] and Pluto [9] but are below those from Mark I [8]. Above 4 GeV, our values are consistent with previous measurements.…”

“…The experimental R-values are in general consistent with theoretical predictions, which is an impressive confirmation of the hypothesis of the three color degrees of freedom for quarks. The measurements of R in the low energy region were performed 15 to 20 years ago in Novosibirsk, Orsay, Frascati, SLAC and Hamburg [3,4,5,6,7,8,9]. Fig.…”

The renormalization group and critical phenomena

“…that experimentalists measure must be interpreted using quantum field theory. Without the internal structure that appears in the theory, the predictions of quantum field theory would disagree with the experimental findings (see, for example, Criegee and Knies, 1982).…”

Measurement of the Total Cross Section for Hadronic Production bye+e−Annihilation at Energies between 2.6–5 GeV

“…This ratio has been measured by many experiments over the center-of-mass (cm) energy range from the hadron production threshold to the Z pole [1]. The measured R values are, in general, consistent with theoretical predictions and provide an impressive confirmation of the hypothesis of three color degrees of freedom for quarks.However, the existing R measurements for cm energies below 5 GeV were performed 17 to 25 years ago [2][3][4][5][6][7][8] and have average experimental uncertainties of about 15%[9]. Uncertainties in the values of R in this energy region limit the precision of the QED running coupling constant evaluated at the mass of the Z boson, a͑M 2 Z ͒, which in turn limits the precision of the determination of the Higgs mass from radiative corrections in the standard model [9][10][11][12][13][14][15].…”