The total cross section for e+e- annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z0 boson, MZ, and the QCD scale parameter, ΛMS, are derived from the fit. The results are MZ=88.6-1.8 +2.0 GeV/c2, and ΛMS=0.15-0.11 +0.16 GeV.
Bibliographical noteFunding Information:
eration of the storage ring. In addition we acknowledge the strong support provided by the staffs of our home institutions. This work has been supported by the Japan Ministry of Education, Science and Culture (Monbusho), the US Department of Energy and National Science Foundation, the Korean Science and Engineering Foundation and Ministry of Education, and the Academia Sinica of the People's Republic of China.