New R values in 2-5 GeV from the BESII at BEPC

Z. G. Zhao

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arXiv · hep-ex/0012038

New R values in 2-5 GeV from the BESII at BEPC

Z. G. Zhao

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Abstract

We report preliminary $R$ values for all 85 energy points scanned in the energy region of 2-5 GeV with the upgraded Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC). The typical uncertainty on the R values we measured is about 7%. The new R values have a significant impact on the predicted mass of the Higgs coming from the global fit to the electroweak data, and will also contribute to the interpretation of the E821 g-2 experiment.

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Z. G. Zhao. 2000-12-16. New R values in 2-5 GeV from the BESII at BEPC. https://arxiv.org/abs/hep-ex/0012038

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