The values of R=σ(e+e−→hadrons)/σ(e+e−→μ+μ−) for 85 center-of-mass energies between 2 and 5 GeV were measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider, with an average uncertainty of ∼7.
@article{arxiv.hep-ex/0105074,
title = {New R Values in 2-5 Gev from the Beijing Spectrometer},
author = {G. S. Huang and representing the BES Collaboration},
journal= {arXiv preprint arXiv:hep-ex/0105074},
year = {2007}
}
Comments
4 pages, 1 figure, 1 table, talk given at XXXVIth Rencontres de Moriond, Electroweak Interactions and Unified Theories, Les Arcs, Savoie, France, March 10-17 2001